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Topical Collection "Feature Papers in Molecular Biology"

Editor

Prof. Dr. Irmgard Tegeder
Website
Collection Editor
Pharmazentrum Frankfurt, Dept. of Clinical Pharmacology, Goethe-University of Frankfurt, Theodor Stern Kai 7, Bd. 74, 4th Fl, 60590 Frankfurt am Main, Germany
Interests: nerve injury and neuropathic pain; pain and aging; central adaptations to chronic pain; multiple sclerosis; neuroinflammation; neuro-immunologic communication; redox signaling; nitric oxide; endocannabinoids and other lipid signaling molecules; progranulin; autophagy
Special Issues and Collections in MDPI journals

Topical Collection Information

Dear colleagues,

This Topical Collection entitled “Feature Papers in Molecular Biology” aims to collect high-quality research articles, communications, and review articles in cutting-edge fields of molecular biology. Since the aim of this Topical Collection is to illustrate, through selected works, frontier research in molecular biology, we encourage Editorial Board Members of the Molecular Biology Section of the International Journal of Molecular Sciences to contribute feature papers reflecting the latest progress in their research field, or to invite relevant experts and colleagues to do so.

Topics include, but are not limited to,

  • Biological activities at the molecular level;
  • Biological processes of cell functions and maintenance;
  • Molecular processes of cell division, senescence and cell death;
  • Biomolecules interactions and cell-to-cell communication;
  • DNA, and RNA biosynthesis, metabolism, interactions and functions;
  • Protein biosynthesis, degradation and functions;
  • Regulation of molecular interactions in a cell;
  • Molecular processes of cell and organelle dynamics;
  • Gene functions, genetics, and genomics;
  • Signaling networks and system biology;
  • Advanced techniques of molecular biology;
  • Structural biology;
  • Developmental biology;
  • Chemical biology;
  • Computational biology;
  • Molecular methodologies, imaging techniques, and bioinformatics.

Prof. Dr. Irmgard Tegeder
Guest Editor

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Keywords

  • molecular biology
  • cell biology
  • signal transduction and regulation
  • cell growth and differentiation
  • apoptosis
  • necroptosis, ferroptosis, autophagy
  • cell cycle
  • macromolecules and complexes
  • gene expression, functions and therapy
  • mutation
  • DNA structure, damage and repair
  • chromatin structure and function
  • nuclear organization
  • polymerase
  • RNA transcription
  • RNA structure and regulation
  • RNA splicing, and polyadenylation
  • protein translation
  • post-translational modifications
  • amino acid
  • proteins
  • protein folding, chaperones, protein degradation and quality control
  • enzyme regulation
  • nucleic acid-protein interactions
  • cell-cell interaction
  • molecular clone
  • sequencing analysis
  • epigenetics
  • proteomics
  • bioinformatics
  • imaging techniques
  • kinesins
  • metabolome
  • transport mechanisms
  • exosome, biological membranes
  • homeostasis

Published Papers (27 papers)

2020

Jump to: 2019

Open AccessReview
Towards a New Understanding of Decision-Making by Hematopoietic Stem Cells
Int. J. Mol. Sci. 2020, 21(7), 2362; https://doi.org/10.3390/ijms21072362 - 29 Mar 2020
Abstract
Cells within the hematopoietic stem cell compartment selectively express receptors for cytokines that have a lineage(s) specific role; they include erythropoietin, macrophage colony-stimulating factor, granulocyte colony-stimulating factor, granulocyte/macrophage colony-stimulating factor and the ligand for the fms-like tyrosine kinase 3. These hematopoietic cytokines can [...] Read more.
Cells within the hematopoietic stem cell compartment selectively express receptors for cytokines that have a lineage(s) specific role; they include erythropoietin, macrophage colony-stimulating factor, granulocyte colony-stimulating factor, granulocyte/macrophage colony-stimulating factor and the ligand for the fms-like tyrosine kinase 3. These hematopoietic cytokines can instruct the lineage fate of hematopoietic stem and progenitor cells in addition to ensuring the survival and proliferation of cells that belong to a particular cell lineage(s). Expression of the receptors for macrophage colony-stimulating factor and granulocyte colony-stimulating factor is positively autoregulated and the presence of the cytokine is therefore likely to enforce a lineage bias within hematopoietic stem cells that express these receptors. In addition to the above roles, macrophage colony-stimulating factor and granulocyte/macrophage colony-stimulating factor are powerful chemoattractants. The multiple roles of some hematopoietic cytokines leads us towards modelling hematopoietic stem cell decision-making whereby these cells can ‘choose’ just one lineage fate and migrate to a niche that both reinforces the fate and guarantees the survival and expansion of cells as they develop. Full article
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Open AccessArticle
Augmenting Vacuolar H+-ATPase Function Prevents Cardiomyocytes from Lipid-Overload Induced Dysfunction
Int. J. Mol. Sci. 2020, 21(4), 1520; https://doi.org/10.3390/ijms21041520 - 23 Feb 2020
Abstract
The diabetic heart is characterized by a shift in substrate utilization from glucose to lipids, which may ultimately lead to contractile dysfunction. This substrate shift is facilitated by increased translocation of lipid transporter CD36 (SR-B2) from endosomes to the sarcolemma resulting in increased [...] Read more.
The diabetic heart is characterized by a shift in substrate utilization from glucose to lipids, which may ultimately lead to contractile dysfunction. This substrate shift is facilitated by increased translocation of lipid transporter CD36 (SR-B2) from endosomes to the sarcolemma resulting in increased lipid uptake. We previously showed that endosomal retention of CD36 is dependent on the proper functioning of vacuolar H+-ATPase (v-ATPase). Excess lipids trigger CD36 translocation through inhibition of v-ATPase function. Conversely, in yeast, glucose availability is known to enhance v-ATPase function, allowing us to hypothesize that glucose availability, via v-ATPase, may internalize CD36 and restore contractile function in lipid-overloaded cardiomyocytes. Increased glucose availability was achieved through (a) high glucose (25 mM) addition to the culture medium or (b) adenoviral overexpression of protein kinase-D1 (a kinase mediating GLUT4 translocation). In HL-1 cardiomyocytes, adult rat and human cardiomyocytes cultured under high-lipid conditions, each treatment stimulated v-ATPase re-assembly, endosomal acidification, endosomal CD36 retention and prevented myocellular lipid accumulation. Additionally, these treatments preserved insulin-stimulated GLUT4 translocation and glucose uptake as well as contractile force. The present findings reveal v-ATPase functions as a key regulator of cardiomyocyte substrate preference and as a novel potential treatment approach for the diabetic heart. Full article
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Open AccessArticle
Effect of Cholesterol on the Organic Cation Transporter OCTN1 (SLC22A4)
Int. J. Mol. Sci. 2020, 21(3), 1091; https://doi.org/10.3390/ijms21031091 - 06 Feb 2020
Abstract
The effect of cholesterol was investigated on the OCTN1 transport activity measured as [14C]-tetraethylamonium or [3H]-acetylcholine uptake in proteoliposomes reconstituted with native transporter extracted from HeLa cells or the human recombinant OCTN1 over-expressed in E. coli. Removal of [...] Read more.
The effect of cholesterol was investigated on the OCTN1 transport activity measured as [14C]-tetraethylamonium or [3H]-acetylcholine uptake in proteoliposomes reconstituted with native transporter extracted from HeLa cells or the human recombinant OCTN1 over-expressed in E. coli. Removal of cholesterol from the native transporter by MβCD before reconstitution led to impairment of transport activity. A similar activity impairment was observed after treatment of proteoliposomes harboring the recombinant (cholesterol-free) protein by MβCD, suggesting that the lipid mixture used for reconstitution contained some cholesterol. An enzymatic assay revealed the presence of 10 µg cholesterol/mg total lipids corresponding to 1% cholesterol in the phospholipid mixture used for the proteoliposome preparation. On the other way around, the activity of the recombinant OCTN1 was stimulated by adding the cholesterol analogue, CHS to the proteoliposome preparation. Optimal transport activity was detected in the presence of 83 µg CHS/ mg total lipids for both [14C]-tetraethylamonium or [3H]-acetylcholine uptake. Kinetic analysis of transport demonstrated that the stimulation of transport activity by CHS consisted in an increase of the Vmax of transport with no changes of the Km. Altogether, the data suggests a direct interaction of cholesterol with the protein. A further support to this interpretation was given by a docking analysis indicating the interaction of cholesterol with some protein sites corresponding to CARC-CRAC motifs. The observed direct interaction of cholesterol with OCTN1 points to a possible direct influence of cholesterol on tumor cells or on acetylcholine transport in neuronal and non-neuronal cells via OCTN1. Full article
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Open AccessArticle
BMAL1 Modulates Epidermal Healing in a Process Involving the Antioxidative Defense Mechanism
Int. J. Mol. Sci. 2020, 21(3), 901; https://doi.org/10.3390/ijms21030901 - 30 Jan 2020
Abstract
The circadian rhythm regulates the physiology and behavior of living organisms in a time-dependent manner. Clock genes have distinct roles including the control over gene expression mediated by the transcriptional activators CLOCK and BMAL1, and the suppression of gene expression mediated by the [...] Read more.
The circadian rhythm regulates the physiology and behavior of living organisms in a time-dependent manner. Clock genes have distinct roles including the control over gene expression mediated by the transcriptional activators CLOCK and BMAL1, and the suppression of gene expression mediated by the transcriptional repressors PER1/2 and CRY1/2. The balance between gene expression and repression is key to the maintenance of tissue homeostasis that is disrupted in the event of an injury. In the skin, a compromised epithelial barrier triggers a cascade of events that culminate in the mobilization of epithelial cells and stem cells. Recruited epithelial cells migrate towards the wound and reestablish the protective epithelial layer of the skin. Although we have recently demonstrated the involvement of BMAL and the PI3K signaling in wound healing, the role of the circadian clock genes in tissue repair remains poorly understood. Here, we sought to understand the role of BMAL1 on skin healing in response to injury. We found that genetic depletion of BMAL1 resulted in delayed healing of the skin as compared to wild-type control mice. Furthermore, we found that loss of Bmal1 was associated with the accumulation of Reactive Oxygen Species Modulator 1 (ROMO1), a protein responsible for inducing the production of intracellular reactive oxygen species (ROS). The slow healing was associated with ROS and superoxide dismutase (SOD) production, and pharmacological inhibition of the oxidative stress signaling (ROS/SOD) led to cellular proliferation, upregulation of Sirtuin 1 (SIRT1), and rescued the skin healing phenotype of Bmal1−/− mice. Overall, our study points to BMAL1 as a key player in tissue regeneration and as a critical regulator of ROMO1 and oxidative stress in the skin. Full article
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Open AccessArticle
Helicase-Like Transcription Factor HLTF and E3 Ubiquitin Ligase SHPRH Confer DNA Damage Tolerance through Direct Interactions with Proliferating Cell Nuclear Antigen (PCNA)
Int. J. Mol. Sci. 2020, 21(3), 693; https://doi.org/10.3390/ijms21030693 - 21 Jan 2020
Abstract
To prevent replication fork collapse and genome instability under replicative stress, DNA damage tolerance (DDT) mechanisms have evolved. The RAD5 homologs, HLTF (helicase-like transcription factor) and SHPRH (SNF2, histone-linker, PHD and RING finger domain-containing helicase), both ubiquitin ligases, are involved in several DDT [...] Read more.
To prevent replication fork collapse and genome instability under replicative stress, DNA damage tolerance (DDT) mechanisms have evolved. The RAD5 homologs, HLTF (helicase-like transcription factor) and SHPRH (SNF2, histone-linker, PHD and RING finger domain-containing helicase), both ubiquitin ligases, are involved in several DDT mechanisms; DNA translesion synthesis (TLS), fork reversal/remodeling and template switch (TS). Here we show that these two human RAD5 homologs contain functional APIM PCNA interacting motifs. Our results show that both the role of HLTF in TLS in HLTF overexpressing cells, and nuclear localization of SHPRH, are dependent on interaction of HLTF and SHPRH with PCNA. Additionally, we detected multiple changes in the mutation spectra when APIM in overexpressed HLTF or SHPRH were mutated compared to overexpressed wild type proteins. In plasmids from cells overexpressing the APIM mutant version of HLTF, we observed a decrease in C to T transitions, the most common mutation caused by UV irradiation, and an increase in mutations on the transcribed strand. These results strongly suggest that direct binding of HLTF and SHPRH to PCNA is vital for their function in DDT. Full article
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2019

Jump to: 2020

Open AccessCommunication
PHLDA1 Does Not Contribute Directly to Heat Shock-Induced Apoptosis of Spermatocytes
Int. J. Mol. Sci. 2020, 21(1), 267; https://doi.org/10.3390/ijms21010267 - 30 Dec 2019
Cited by 1
Abstract
Spermatocytes are among the most heat-sensitive cells and the exposure of testes to heat shock results in their Heat Shock Factor 1 (HSF1)-mediated apoptosis. Several lines of evidence suggest that pleckstrin-homology-like domain family A, member 1 (PHLDA1) plays a role in promoting heat [...] Read more.
Spermatocytes are among the most heat-sensitive cells and the exposure of testes to heat shock results in their Heat Shock Factor 1 (HSF1)-mediated apoptosis. Several lines of evidence suggest that pleckstrin-homology-like domain family A, member 1 (PHLDA1) plays a role in promoting heat shock-induced cell death in spermatogenic cells, yet its precise physiological role is not well understood. Aiming to elucidate the hypothetical role of PHLDA1 in HSF1-mediated apoptosis of spermatogenic cells we characterized its expression in mouse testes during normal development and after heat shock. We stated that transcription of Phlda1 is upregulated by heat shock in many adult mouse organs including the testes. Analyzes of the Phlda1 expression during postnatal development indicate that it is expressed in pre-meiotic or somatic cells of the testis. It starts to be transcribed much earlier than spermatocytes are fully developed and its transcripts and protein products do not accumulate further in the later stages. Moreover, neither heat shock nor expression of constitutively active HSF1 results in the accumulation of PHLDA1 protein in meiotic and post-meiotic cells although both conditions induce massive apoptosis of spermatocytes. Furthermore, the overexpression of PHLDA1 in NIH3T3 cells leads to cell detachment, yet classical apoptosis is not observed. Therefore, our findings indicate that PHLDA1 cannot directly contribute to the heat-induced apoptosis of spermatocytes. Instead, PHLDA1 could hypothetically participate in death of spermatocytes indirectly via activation of changes in the somatic or pre-meiotic cells present in the testes. Full article
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Open AccessReview
Are Leukaemic Stem Cells Restricted to a Single Cell Lineage?
Int. J. Mol. Sci. 2020, 21(1), 45; https://doi.org/10.3390/ijms21010045 - 19 Dec 2019
Abstract
Cancer-stem-cell theory states that most, if not all, cancers arise from a stem/uncommitted cell. This theory revolutionised our view to reflect that cancer consists of a hierarchy of cells that mimic normal cell development. Elegant studies of twins who both developed acute lymphoblastic [...] Read more.
Cancer-stem-cell theory states that most, if not all, cancers arise from a stem/uncommitted cell. This theory revolutionised our view to reflect that cancer consists of a hierarchy of cells that mimic normal cell development. Elegant studies of twins who both developed acute lymphoblastic leukaemia in childhood revealed that at least two genomic insults are required for cancer to develop. These ‘hits’ do not appear to confer a growth advantage to cancer cells, nor do cancer cells appear to be better equipped to survive than normal cells. Cancer cells created by investigators by introducing specific genomic insults generally belong to one cell lineage. For example, transgenic mice in which the LIM-only 2 (LMO2, associated with human acute T-lymphoblastic leukaemia) and BCR-ABLp210 (associated with human chronic myeloid leukaemia) oncogenes were active solely within the haematopoietic stem-cell compartment developed T-lymphocyte and neutrophil lineage-restricted leukaemia, respectively. This recapitulated the human form of these diseases. This ‘hardwiring’ of lineage affiliation, either throughout leukaemic stem cell development or at a particular stage, is different to the behaviour of normal haematopoietic stem cells. While normal cells directly commit to a developmental pathway, they also remain versatile and can develop into a terminally differentiated cell that is not part of the initial lineage. Many cancer stem cells do not have this versatility, and this is an essential difference between normal and cancer stem cells. In this report, we review findings that support this notion. Full article
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Open AccessArticle
A Paradigm in Immunochemistry, Revealed by Monoclonal Antibodies to Spatially Distinct Epitopes on Syntenin-1
Int. J. Mol. Sci. 2019, 20(23), 6035; https://doi.org/10.3390/ijms20236035 - 29 Nov 2019
Abstract
Syntenin-1 is an essential multi-functional adaptor protein, which has multiple roles in membrane trafficking and exosome biogenesis, as well as scaffolding interactions with either the actin cytoskeleton or focal adhesions. However, how this functional multiplicity relates to syntenin-1 distribution in different endosome compartments [...] Read more.
Syntenin-1 is an essential multi-functional adaptor protein, which has multiple roles in membrane trafficking and exosome biogenesis, as well as scaffolding interactions with either the actin cytoskeleton or focal adhesions. However, how this functional multiplicity relates to syntenin-1 distribution in different endosome compartments or other intracellular locations and its underlying involvement in cancer pathogenesis have yet to be fully defined. To help facilitate the investigation of syntenin-1 biology, we developed two specific monoclonal antibodies (Synt-2C6 and Synt-3A11) to spatially distinct linear sequence epitopes on syntenin-1, which were each designed to be unique at the six-amino acid level. These antibodies produced very different intracellular staining patterns, with Synt-2C6 detecting endosomes and Synt-3A11 producing a fibrillar staining pattern suggesting a cytoskeletal localisation. Treatment of cells with Nocodazole altered the intracellular localisation of Synt-3A11, which was consistent with the syntenin-1 protein interacting with microtubules. In prostate tissue biopsies, Synt-3A11 defined atrophy and early-stage prostate cancer, whereas Synt-2C6 only showed minimal interaction with atrophic tissue. This highlights a critical need for site-specific antibodies and a knowledge of their reactivity to define differential protein distributions, interactions and functions, which may differ between normal and malignant cells. Full article
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Open AccessArticle
Caspase-8 Regulates Endoplasmic Reticulum Stress-Induced Necroptosis Independent of the Apoptosis Pathway in Auditory Cells
Int. J. Mol. Sci. 2019, 20(23), 5896; https://doi.org/10.3390/ijms20235896 - 24 Nov 2019
Cited by 3
Abstract
The aim of this study is to elucidate the detailed mechanism of endoplasmic reticulum (ER) stress-induced auditory cell death based on the function of the initiator caspases and molecular complex of necroptosis. Here, we demonstrated that ER stress initiates not only caspase-9-dependent intrinsic [...] Read more.
The aim of this study is to elucidate the detailed mechanism of endoplasmic reticulum (ER) stress-induced auditory cell death based on the function of the initiator caspases and molecular complex of necroptosis. Here, we demonstrated that ER stress initiates not only caspase-9-dependent intrinsic apoptosis along with caspase-3, but also receptor-interacting serine/threonine kinase (RIPK)1-dependent necroptosis in auditory cells. We observed the ultrastructural characteristics of both apoptosis and necroptosis in tunicamycin-treated cells under transmission electron microscopy (TEM). We demonstrated that ER stress-induced necroptosis was dependent on the induction of RIPK1, negatively regulated by caspase-8 in auditory cells. Our data suggested that ER stress-induced intrinsic apoptosis depends on the induction of caspase-9 along with caspase-3 in auditory cells. The results of this study reveal that necroptosis could exist for the alternative backup cell death route of apoptosis in auditory cells under ER stress. Interestingly, our data results in a surge in the recognition that therapies aimed at the inner ear protection effect by caspase inhibitors like zVAD-fmk might arrest apoptosis but can also have the unanticipated effect of promoting necroptosis. Thus, RIPK1-dependent necroptosis would be a new therapeutic target for the treatment of sensorineural hearing loss due to ER stress. Full article
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Open AccessArticle
A Single Synonymous Variant (c.354G>A [p.P118P]) in ADAMTS13 Confers Enhanced Specific Activity
Int. J. Mol. Sci. 2019, 20(22), 5734; https://doi.org/10.3390/ijms20225734 - 15 Nov 2019
Cited by 1
Abstract
Synonymous variants within coding regions may influence protein expression and function. We have previously reported increased protein expression levels ex vivo (~120% in comparison to wild-type) from a synonymous polymorphism variant, c.354G>A [p.P118P], of the ADAMTS13 gene, encoding a plasma protease responsible for [...] Read more.
Synonymous variants within coding regions may influence protein expression and function. We have previously reported increased protein expression levels ex vivo (~120% in comparison to wild-type) from a synonymous polymorphism variant, c.354G>A [p.P118P], of the ADAMTS13 gene, encoding a plasma protease responsible for von Willebrand Factor (VWF) degradation. In the current study, we investigated the potential mechanism(s) behind the increased protein expression levels from this variant and its effect on ADAMTS13 physico-chemical properties. Cell-free assays showed enhanced translation of the c.354G>A variant and the analysis of codon usage characteristics suggested that introduction of the frequently used codon/codon pair(s) may have been potentially responsible for this effect. Limited proteolysis, however, showed no substantial influence of altered translation on protein conformation. Analysis of post-translational modifications also showed no notable differences but identified three previously unreported glycosylation markers. Despite these similarities, p.P118P variant unexpectedly showed higher specific activity. Structural analysis using modeled interactions indicated that subtle conformational changes arising from altered translation kinetics could affect interactions between an exosite of ADAMTS13 and VWF resulting in altered specific activity. This report highlights how a single synonymous nucleotide variation can impact cellular expression and specific activity in the absence of measurable impact on protein structure. Full article
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Open AccessArticle
EPO and TMBIM3/GRINA Promote the Activation of the Adaptive Arm and Counteract the Terminal Arm of the Unfolded Protein Response after Murine Transient Cerebral Ischemia
Int. J. Mol. Sci. 2019, 20(21), 5421; https://doi.org/10.3390/ijms20215421 - 31 Oct 2019
Abstract
Ischemic stroke is known to cause the accumulation of misfolded proteins and loss of calcium homeostasis leading to impairment of endoplasmic reticulum (ER) function. The unfolded protein response (UPR) is an ER-located and cytoprotective pathway that aims to resolve ER stress. Transmembrane BAX [...] Read more.
Ischemic stroke is known to cause the accumulation of misfolded proteins and loss of calcium homeostasis leading to impairment of endoplasmic reticulum (ER) function. The unfolded protein response (UPR) is an ER-located and cytoprotective pathway that aims to resolve ER stress. Transmembrane BAX inhibitor-1 motif-containing (TMBIM) protein family member TMBIM3/GRINA is highly expressed in the brain and mostly located at the ER membrane suppressing ER calcium release by inositol-1,4,5-trisphosphate receptors. GRINA confers neuroprotection and is regulated by erythropoietin (EPO) after murine cerebral ischemia. However, the role of GRINA and the impact of EPO treatment on the post-ischemic UPR have not been elucidated yet. We subjected GRINA-deficient (Grina−/−) and wildtype mice to transient (30 min) middle cerebral artery occlusion (tMCAo) followed by 6 h or 72 h of reperfusion. We administered EPO or saline 0, 24 and 48 h after tMCAo/sham surgery. Oxygen–glucose deprivation (OGD) and pharmacological stimulation of the UPR using Tunicamycin and Thapsigargin were carried out in primary murine cortical mixed cell cultures. Treatment with the PERK-inhibitor GSK-2606414, IRE1a-RNase-inhibitor STF-083010 and EPO was performed 1 h prior to either 1 h, 2 h or 3 h of OGD. We found earlier and larger infarct demarcations in Grina−/− mice compared to wildtype mice, which was accompanied by a worse neurological outcome and an abolishment of EPO-mediated neuroprotection after ischemic stroke. In addition, GRINA-deficiency increased apoptosis and the activation of the corresponding PERK arm of the UPR after stroke. EPO enhanced the post-ischemic activation of pro-survival IRE1a and counteracted the pro-apoptotic PERK branch of the UPR. Both EPO and the PERK-inhibitor GSK-2606414 reduced cell death and regulated Grina mRNA levels after OGD. In conclusion, GRINA plays a crucial role in post-ischemic UPR and the use of both GSK-2606414 and EPO might lead to neuroprotection. Full article
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Open AccessArticle
Renal Artery Stenosis Alters Gene Expression in Swine Scattered Tubular-Like Cells
Int. J. Mol. Sci. 2019, 20(20), 5069; https://doi.org/10.3390/ijms20205069 - 12 Oct 2019
Abstract
Background: Scattered tubular-like cells (STCs) proliferate and differentiate to support neighboring injured renal tubular cells during recovery from insults. Renal artery stenosis (RAS) induces renal ischemia and hypertension and leads to loss of kidney function, but whether RAS alters renal endogenous repair mechanisms, [...] Read more.
Background: Scattered tubular-like cells (STCs) proliferate and differentiate to support neighboring injured renal tubular cells during recovery from insults. Renal artery stenosis (RAS) induces renal ischemia and hypertension and leads to loss of kidney function, but whether RAS alters renal endogenous repair mechanisms, such as STCs, remains unknown. We hypothesize that RAS in swine modifies the messenger RNA (mRNA) profile of STCs, blunting their in vitro reparative capacity. Methods: CD24+/CD133+ STCs were isolated from pig kidneys after 10-weeks of RAS or sham (n = 3 each) and their gene cargo analyzed using high-throughput mRNAseq. Expression profiles for upregulated and downregulated mRNAs in RAS-STCs were functionally interpreted by gene ontology analysis. STC activation was assessed by counting the total number of STCs in pig kidney sections using flow cytometry, whereas cell proliferation was assessed in vitro. Results: Of all expressed genes, 1430 genes were upregulated and 315 downregulated in RAS- versus Normal-STCs. Expression of selected candidate genes followed the same fold change directions as the mRNAseq findings. Genes upregulated in RAS-STCs were involved in cell adhesion, extracellular matrix remodeling, and kidney development, whereas those downregulated in RAS-STCs are related to cell cycle and cytoskeleton. The percentage of STCs from dissociated kidney cells was higher in RAS versus Normal pigs, but their proliferation rate was blunted. Conclusions: Renal ischemia and hypertension in swine induce changes in the mRNA profile of STCs, associated with increased STC activation and impaired proliferation. These observations suggest that RAS may alter the reparative capacity of STCs. Full article
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Open AccessArticle
Systematic Approach to Developing Splice Modulating Antisense Oligonucleotides
Int. J. Mol. Sci. 2019, 20(20), 5030; https://doi.org/10.3390/ijms20205030 - 11 Oct 2019
Cited by 1
Abstract
The process of pre-mRNA splicing is a common and fundamental step in the expression of most human genes. Alternative splicing, whereby different splice motifs and sites are recognised in a developmental and/or tissue-specific manner, contributes to genetic plasticity and diversity of gene expression. [...] Read more.
The process of pre-mRNA splicing is a common and fundamental step in the expression of most human genes. Alternative splicing, whereby different splice motifs and sites are recognised in a developmental and/or tissue-specific manner, contributes to genetic plasticity and diversity of gene expression. Redirecting pre-mRNA processing of various genes has now been validated as a viable clinical therapeutic strategy, providing treatments for Duchenne muscular dystrophy (inducing specific exon skipping) and spinal muscular atrophy (promoting exon retention). We have designed and evaluated over 5000 different antisense oligonucleotides to alter splicing of a variety of pre-mRNAs, from the longest known human pre-mRNA to shorter, exon-dense primary gene transcripts. Here, we present our guidelines for designing, evaluating and optimising splice switching antisense oligomers in vitro. These systematic approaches assess several critical factors such as the selection of target splicing motifs, choice of cells, various delivery reagents and crucial aspects of validating assays for the screening of antisense oligonucleotides composed of 2′-O-methyl modified bases on a phosphorothioate backbone. Full article
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Open AccessArticle
Endoplasmic Reticulum Stress Increases DUSP5 Expression via PERK-CHOP Pathway, Leading to Hepatocyte Death
Int. J. Mol. Sci. 2019, 20(18), 4369; https://doi.org/10.3390/ijms20184369 - 05 Sep 2019
Abstract
Hepatocyte death is critical for the pathogenesis of liver disease progression, which is closely associated with endoplasmic reticulum (ER) stress responses. However, the molecular basis for ER stress-mediated hepatocyte injury remains largely unknown. This study investigated the effect of ER stress on dual-specificity [...] Read more.
Hepatocyte death is critical for the pathogenesis of liver disease progression, which is closely associated with endoplasmic reticulum (ER) stress responses. However, the molecular basis for ER stress-mediated hepatocyte injury remains largely unknown. This study investigated the effect of ER stress on dual-specificity phosphatase 5 (DUSP5) expression and its role in hepatocyte death. Analysis of Gene Expression Omnibus (GEO) database showed that hepatic DUSP5 levels increased in the patients with liver fibrosis, which was verified in mouse models of liver diseases with ER stress. DUSP5 expression was elevated in both fibrotic and acutely injured liver of mice treated with liver toxicants. Treatment of ER stress inducers enhanced DUSP5 expression in hepatocytes, which was validated in vivo condition. The induction of DUSP5 by ER stress was blocked by either treatment with a chemical inhibitor of the protein kinase RNA-like endoplasmic reticulum kinase (PERK) pathway, or knockdown of C/EBP homologous protein (CHOP), whereas it was not affected by the silencing of IRE1 or ATF6. In addition, DUSP5 overexpression decreased extracellular-signal-regulated kinase (ERK) phosphorylation, but increased cleaved caspase-3 levels. Moreover, the reduction of cell viability under ER stress condition was attenuated by DUSP5 knockdown. In conclusion, DUSP5 expression is elevated in hepatocytes by ER stress through the PERK-CHOP pathway, contributing to hepatocyte death possibly through ERK inhibition. Full article
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Open AccessArticle
Modulation of Tetraspanin 32 (TSPAN32) Expression in T Cell-Mediated Immune Responses and in Multiple Sclerosis
Int. J. Mol. Sci. 2019, 20(18), 4323; https://doi.org/10.3390/ijms20184323 - 04 Sep 2019
Cited by 7
Abstract
Tetraspanins are a conserved family of proteins involved in a number of biological processes including, cell–cell interactions, fertility, cancer metastasis and immune responses. It has previously been shown that TSPAN32 knockout mice have normal hemopoiesis and B-cell responses, but hyperproliferative T cells. Here, [...] Read more.
Tetraspanins are a conserved family of proteins involved in a number of biological processes including, cell–cell interactions, fertility, cancer metastasis and immune responses. It has previously been shown that TSPAN32 knockout mice have normal hemopoiesis and B-cell responses, but hyperproliferative T cells. Here, we show that TSPAN32 is expressed at higher levels in the lymphoid lineage as compared to myeloid cells. In vitro activation of T helper cells via anti-CD3/CD28 is associated with a significant downregulation of TSPAN32. Interestingly, engagement of CD3 is sufficient to modulate TSPAN32 expression, and its effect is potentiated by costimulation with anti-CD28, but not anti-CTLA4, -ICOS nor -PD1. Accordingly, we measured the transcriptomic levels of TSPAN32 in polarized T cells under Th1 and Th2 conditions and TSPAN32 resulted significantly reduced as compared with unstimulated cells. On the other hand, in Treg cells, TSPAN32 underwent minor changes upon activation. The in vitro data were finally translated into the context of multiple sclerosis (MS). Encephalitogenic T cells from Myelin Oligodendrocyte Glycoprotein (MOG)-Induced Experimental Autoimmune Encephalomyelitis (EAE) mice showed significantly lower levels of TSPAN32 and increased levels of CD9, CD53, CD82 and CD151. Similarly, in vitro-activated circulating CD4 T cells from MS patients showed lower levels of TSPAN32 as compared with cells from healthy donors. Overall, these data suggest an immunoregulatory role for TSPAN32 in T helper immune response and may represent a target of future immunoregulatory therapies for T cell-mediated autoimmune diseases. Full article
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Open AccessReview
Improving Lodging Resistance: Using Wheat and Rice as Classical Examples
Int. J. Mol. Sci. 2019, 20(17), 4211; https://doi.org/10.3390/ijms20174211 - 28 Aug 2019
Cited by 1
Abstract
One of the most chronic constraints to crop production is the grain yield reduction near the crop harvest stage by lodging worldwide. This is more prevalent in cereal crops, particularly in wheat and rice. Major factors associated with lodging involve morphological and anatomical [...] Read more.
One of the most chronic constraints to crop production is the grain yield reduction near the crop harvest stage by lodging worldwide. This is more prevalent in cereal crops, particularly in wheat and rice. Major factors associated with lodging involve morphological and anatomical traits along with the chemical composition of the stem. These traits have built up the remarkable relationship in wheat and rice genotypes either prone to lodging or displaying lodging resistance. In this review, we have made a comparison of our conceptual perceptions with foregoing published reports and proposed the fundamental controlling techniques that could be practiced to control the devastating effects of lodging stress. The management of lodging stress is, however, reliant on chemical, agronomical, and genetic factors that are reducing the risk of lodging threat in wheat and rice. But, still, there are many questions remain to be answered to elucidate the complex lodging phenomenon, so agronomists, breeders, physiologists, and molecular biologists require further investigation to address this challenging problem. Full article
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Open AccessArticle
Compromised Barrier Function in Human Induced Pluripotent Stem-Cell-Derived Retinal Pigment Epithelial Cells from Type 2 Diabetic Patients
Int. J. Mol. Sci. 2019, 20(15), 3773; https://doi.org/10.3390/ijms20153773 - 01 Aug 2019
Cited by 3
Abstract
In diabetic patients, high blood glucose induces alterations in retinal function and can lead to visual impairment due to diabetic retinopathy. In immortalized retinal pigment epithelial (RPE) cultures, high glucose concentrations are shown to lead to impairment in epithelial barrier properties. For the [...] Read more.
In diabetic patients, high blood glucose induces alterations in retinal function and can lead to visual impairment due to diabetic retinopathy. In immortalized retinal pigment epithelial (RPE) cultures, high glucose concentrations are shown to lead to impairment in epithelial barrier properties. For the first time, the induced pluripotent stem-cell-derived retinal pigment epithelium (hiPSC-RPE) cell lines derived from type 2 diabetics and healthy control patients were utilized to assess the effects of glucose concentration on the cellular functionality. We show that both type 2 diabetic and healthy control hiPSC-RPE lines differentiate and mature well, both in high and normal glucose concentrations, express RPE specific genes, secrete pigment epithelium derived factor, and form a polarized cell layer. Here, type 2 diabetic hiPSC-RPE cells had a decreased barrier function compared to controls. Added insulin increased the epithelial cell layer tightness in normal glucose concentrations, and the effect was more evident in type 2 diabetics than in healthy control hiPSC-RPE cells. In addition, the preliminary functionality assessments showed that type 2 diabetic hiPSC-RPE cells had attenuated autophagy detected via ubiquitin-binding protein p62/Sequestosome-1 (p62/SQSTM1) accumulation, and lowered pro- matrix metalloproteinase 2 (proMMP2) as well as increased pro-MMP9 secretion. These results suggest that the cellular ability to tolerate stress is possibly decreased in type 2 diabetic RPE cells. Full article
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Open AccessReview
Mast Cells in Cardiovascular Disease: From Bench to Bedside
Int. J. Mol. Sci. 2019, 20(14), 3395; https://doi.org/10.3390/ijms20143395 - 10 Jul 2019
Cited by 1
Abstract
Mast cells are pluripotent leukocytes that reside in the mucosa and connective tissue. Recent studies show an increased prevalence of cardiovascular disease among patients with mastocytosis, which is a hematological disease that is characterized by the accumulation of mast cells due to clonal [...] Read more.
Mast cells are pluripotent leukocytes that reside in the mucosa and connective tissue. Recent studies show an increased prevalence of cardiovascular disease among patients with mastocytosis, which is a hematological disease that is characterized by the accumulation of mast cells due to clonal proliferation. This association suggests an important role for mast cells in cardiovascular disease. Indeed, the evidence establishing the contribution of mast cells to the development and progression of atherosclerosis is continually increasing. Mast cells may contribute to plaque formation by stimulating the formation of foam cells and causing a pro-inflammatory micro-environment. In addition, these cells are able to promote plaque instability by neo-vessel formation and also by inducing intraplaque hemorrhage. Furthermore, mast cells appear to stimulate the formation of fibrosis after a cardiac infarction. In this review, the available data on the role of mast cells in cardiovascular disease are summarized, containing both in vitro research and animal studies, followed by a discussion of human data on the association between cardiovascular morbidity and diseases in which mast cells are important: Kounis syndrome, mastocytosis and allergy. Full article
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Open AccessArticle
Calcium Homeostasis Is Modified in Skeletal Muscle Fibers of Small Ankyrin1 Knockout Mice
Int. J. Mol. Sci. 2019, 20(13), 3361; https://doi.org/10.3390/ijms20133361 - 09 Jul 2019
Cited by 1
Abstract
Small Ankyrins (sAnk1) are muscle-specific isoforms generated by the Ank1 gene that participate in the organization of the sarcoplasmic reticulum (SR) of striated muscles. Accordingly, the volume of SR tubules localized around the myofibrils is strongly reduced in skeletal muscle fibers of 4- [...] Read more.
Small Ankyrins (sAnk1) are muscle-specific isoforms generated by the Ank1 gene that participate in the organization of the sarcoplasmic reticulum (SR) of striated muscles. Accordingly, the volume of SR tubules localized around the myofibrils is strongly reduced in skeletal muscle fibers of 4- and 10-month-old sAnk1 knockout (KO) mice, while additional structural alterations only develop with aging. To verify whether the lack of sAnk1 also alters intracellular Ca2+ handling, cytosolic Ca2+ levels were analyzed in stimulated skeletal muscle fibers from 4- and 10-month-old sAnk1 KO mice. The SR Ca2+ content was reduced in sAnk1 KO mice regardless of age. The amplitude of the Ca2+ transients induced by depolarizing pulses was decreased in myofibers of sAnk1 KO with respect to wild type (WT) fibers, while their voltage dependence was not affected. Furthermore, analysis of spontaneous Ca2+ release events (sparks) on saponin-permeabilized muscle fibers indicated that the frequency of sparks was significantly lower in fibers from 4-month-old KO mice compared to WT. Furthermore, both the amplitude and spatial spread of sparks were significantly smaller in muscle fibers from both 4- and 10-month-old KO mice compared to WT. These data suggest that the absence of sAnk1 results in an impairment of SR Ca2+ release, likely as a consequence of a decreased Ca2+ store due to the reduction of the SR volume in sAnk1 KO muscle fibers. Full article
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Open AccessArticle
The TAFs of TFIID Bind and Rearrange the Topology of the TATA-Less RPS5 Promoter
Int. J. Mol. Sci. 2019, 20(13), 3290; https://doi.org/10.3390/ijms20133290 - 04 Jul 2019
Abstract
The general transcription factor TFIID is a core promoter selectivity factor that recognizes DNA sequence elements and nucleates the assembly of a pre-initiation complex (PIC). The mechanism by which TFIID recognizes the promoter is poorly understood. The TATA-box binding protein (TBP) is a [...] Read more.
The general transcription factor TFIID is a core promoter selectivity factor that recognizes DNA sequence elements and nucleates the assembly of a pre-initiation complex (PIC). The mechanism by which TFIID recognizes the promoter is poorly understood. The TATA-box binding protein (TBP) is a subunit of the multi-protein TFIID complex believed to be key in this process. We reconstituted transcription from highly purified components on a ribosomal protein gene (RPS5) and discovered that TFIIDΔTBP binds and rearranges the promoter DNA topology independent of TBP. TFIIDΔTBP binds ~200 bp of the promoter and changes the DNA topology to a larger extent than the nucleosome core particle. We show that TBP inhibits the DNA binding activities of TFIIDΔTBP and conclude that the complete TFIID complex may represent an auto-inhibited state. Furthermore, we show that the DNA binding activities of TFIIDΔTBP are required for assembly of a PIC poised to select the correct transcription start site (TSS). Full article
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Open AccessCommunication
In Vivo Piggybac-Based Gene Delivery towards Murine Pancreatic Parenchyma Confers Sustained Expression of Gene of Interest
Int. J. Mol. Sci. 2019, 20(13), 3116; https://doi.org/10.3390/ijms20133116 - 26 Jun 2019
Cited by 1
Abstract
The pancreas is a glandular organ that functions in the digestive system and endocrine system of vertebrates. The most common disorders involving the pancreas are diabetes, pancreatitis, and pancreatic cancer. In vivo gene delivery targeting the pancreas is important for preventing or curing [...] Read more.
The pancreas is a glandular organ that functions in the digestive system and endocrine system of vertebrates. The most common disorders involving the pancreas are diabetes, pancreatitis, and pancreatic cancer. In vivo gene delivery targeting the pancreas is important for preventing or curing such diseases and for exploring the biological function of genes involved in the pathogenesis of these diseases. Our previous experiments demonstrated that adult murine pancreatic cells can be efficiently transfected by exogenous plasmid DNA following intraparenchymal injection and subsequent in vivo electroporation using tweezer-type electrodes. Unfortunately, the induced gene expression was transient. Transposon-based gene delivery, such as that facilitated by piggyBac (PB), is known to confer stable integration of a gene of interest (GOI) into host chromosomes, resulting in sustained expression of the GOI. In this study, we investigated the use of the PB transposon system to achieve stable gene expression when transferred into murine pancreatic cells using the above-mentioned technique. Expression of the GOI (coding for fluorescent protein) continued for at least 1.5 months post-gene delivery. Splinkerette-PCR-based analysis revealed the presence of the consensus sequence TTAA at the junctional portion between host chromosomes and the transgenes; however, this was not observed in all samples. This plasmid-based PB transposon system enables constitutive expression of the GOI in pancreas for potential therapeutic and biological applications. Full article
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Open AccessArticle
Immortalized Human hTert/KER-CT Keratinocytes a Model System for Research on Desmosomal Adhesion and Pathogenesis of Pemphigus Vulgaris
Int. J. Mol. Sci. 2019, 20(13), 3113; https://doi.org/10.3390/ijms20133113 - 26 Jun 2019
Abstract
Pemphigus Vulgaris is an autoimmune disease that results in blister formation in the epidermis and in mucosal tissues due to antibodies recognizing desmosomal cadherins, mainly desmoglein-3 and -1. Studies on the molecular mechanisms of Pemphigus have mainly been carried out using the spontaneously [...] Read more.
Pemphigus Vulgaris is an autoimmune disease that results in blister formation in the epidermis and in mucosal tissues due to antibodies recognizing desmosomal cadherins, mainly desmoglein-3 and -1. Studies on the molecular mechanisms of Pemphigus have mainly been carried out using the spontaneously immortalized human keratinocyte cell line HaCaT or in primary keratinocytes. However, both cell systems have suboptimal features, with HaCaT cells exhibiting a large number of chromosomal aberrations and mutated p53 tumor suppressor, whereas primary keratinocytes are short-lived, heterogeneous and not susceptible to genetic modifications due to their restricted life-span. We have here tested the suitability of the commercially available human keratinocyte cell line hTert/KER-CT as a model system for research on epidermal cell adhesion and Pemphigus pathomechanisms. We here show that hTert cells exhibit a calcium dependent expression of desmosomal cadherins and are well suitable for typical assays used for studies on Pemphigus, such as sequential detergent extraction and Dispase-based dissociation assay. Treatment with Pemphigus auto-antibodies results in loss of monolayer integrity and altered localization of desmoglein-3, as well as loss of colocalization with flotillin-2. Our findings demonstrate that hTert cells are well suitable for studies on epidermal cell adhesion and Pemphigus pathomechanisms. Full article
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Open AccessArticle
Molecular Cloning and Sexually Dimorphic Expression Analysis of nanos2 in the Sea Urchin, Mesocentrotus nudus
Int. J. Mol. Sci. 2019, 20(11), 2705; https://doi.org/10.3390/ijms20112705 - 01 Jun 2019
Abstract
Sea urchin (Mesocentrotus nudus) is an economically important mariculture species in China and the gonads are the solely edible parts to human. The molecular mechanisms of gonad development have attracted increasing attention in recent years. Although the nanos2 gene has been [...] Read more.
Sea urchin (Mesocentrotus nudus) is an economically important mariculture species in China and the gonads are the solely edible parts to human. The molecular mechanisms of gonad development have attracted increasing attention in recent years. Although the nanos2 gene has been identified as a germ cell marker in several invertebrates, little is known about nanos2 in adult sea urchins. Hereinto, we report the characterization of Mnnano2, an M. nudus nanos2 homology gene. Mnnanos2 is a maternal factor and can be detected continuously during embryogenesis and early ontogeny. Real-time quantitative PCR (RT-qPCR) and section in situ hybridization (ISH) analysis revealed a dynamic and sexually dimorphic expression pattern of Mnnano2 in the gonads. Its expression reached the maximal level at Stage 2 along with the gonad development in both ovary and testis. In the ovary, Mnnanos2 is specifically expressed in germ cells. In contrast, Mnnanos2 is expressed in both nutritive phagocytes (NP) cells and male germ cells in testis. Moreover, knocking down of Mnnanos2 by means of RNA interference (RNAi) reduced nanos2 and boule expression but conversely increased the expression of foxl2. Therefore, our data suggest that Mnnanos2 may serve as a female germ cell marker during gametogenesis and provide chances to uncover its function in adult sea urchin. Full article
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Open AccessReview
Akt Signaling in Macrophage Polarization, Survival, and Atherosclerosis
Int. J. Mol. Sci. 2019, 20(11), 2703; https://doi.org/10.3390/ijms20112703 - 01 Jun 2019
Cited by 3
Abstract
The PI3K/Akt pathway plays a crucial role in the survival, proliferation, and migration of macrophages, which may impact the development of atherosclerosis. Changes in Akt isoforms or modulation of the Akt activity levels in macrophages significantly affect their polarization phenotype and consequently atherosclerosis [...] Read more.
The PI3K/Akt pathway plays a crucial role in the survival, proliferation, and migration of macrophages, which may impact the development of atherosclerosis. Changes in Akt isoforms or modulation of the Akt activity levels in macrophages significantly affect their polarization phenotype and consequently atherosclerosis in mice. Moreover, the activity levels of Akt signaling determine the viability of monocytes/macrophages and their resistance to pro-apoptotic stimuli in atherosclerotic lesions. Therefore, elimination of pro-apoptotic factors as well as factors that antagonize or suppress Akt signaling in macrophages increases cell viability, protecting them from apoptosis, and this markedly accelerates atherosclerosis in mice. In contrast, inhibition of Akt signaling by the ablation of Rictor in myeloid cells, which disrupts mTORC2 assembly, significantly decreases the viability and proliferation of blood monocytes and macrophages with the suppression of atherosclerosis. In addition, monocytes and macrophages exhibit a threshold effect for Akt protein levels in their ability to survive. Ablation of two Akt isoforms, preserving only a single Akt isoform in myeloid cells, markedly compromises monocyte and macrophage viability, inducing monocytopenia and diminishing early atherosclerosis. These recent advances in our understanding of Akt signaling in macrophages in atherosclerosis may have significant relevance in the burgeoning field of cardio-oncology, where PI3K/Akt inhibitors being tested in cancer patients can have significant cardiovascular and metabolic ramifications. Full article
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Open AccessArticle
The Impact of the C-Terminal Region on the Interaction of Topoisomerase II Alpha with Mitotic Chromatin
Int. J. Mol. Sci. 2019, 20(5), 1238; https://doi.org/10.3390/ijms20051238 - 12 Mar 2019
Cited by 2
Abstract
Type II topoisomerase enzymes are essential for resolving DNA topology problems arising through various aspects of DNA metabolism. In vertebrates two isoforms are present, one of which (TOP2A) accumulates on chromatin during mitosis. Moreover, TOP2A targets the mitotic centromere during prophase, persisting there [...] Read more.
Type II topoisomerase enzymes are essential for resolving DNA topology problems arising through various aspects of DNA metabolism. In vertebrates two isoforms are present, one of which (TOP2A) accumulates on chromatin during mitosis. Moreover, TOP2A targets the mitotic centromere during prophase, persisting there until anaphase onset. It is the catalytically-dispensable C-terminal domain of TOP2 that is crucial in determining this isoform-specific behaviour. In this study we show that, in addition to the recently identified chromatin tether domain, several other features of the alpha-C-Terminal Domain (CTD). influence the mitotic localisation of TOP2A. Lysine 1240 is a major SUMOylation target in cycling human cells and the efficiency of this modification appears to be influenced by T1244 and S1247 phosphorylation. Replacement of K1240 by arginine results in fewer cells displaying centromeric TOP2A accumulation during prometaphase-metaphase. The same phenotype is displayed by cells expressing TOP2A in which either of the mitotic phosphorylation sites S1213 or S1247 has been substituted by alanine. Conversely, constitutive modification of TOP2A by fusion to SUMO2 exerts the opposite effect. FRAP analysis of protein mobility indicates that post-translational modification of TOP2A can influence the enzyme’s residence time on mitotic chromatin, as well as its subcellular localisation. Full article
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Open AccessArticle
Long Non Coding RNA H19: A New Player in Hypoxia-Induced Multiple Myeloma Cell Dissemination
Int. J. Mol. Sci. 2019, 20(4), 801; https://doi.org/10.3390/ijms20040801 - 13 Feb 2019
Cited by 4
Abstract
The long non-coding RNA H19 (lncH19) is broadly transcribed in the first stage of development and silenced in most cells of an adult organism; it appears again in several tumors where, through different molecular mediators, promotes cell proliferation, motility and metastases. LncH19 has [...] Read more.
The long non-coding RNA H19 (lncH19) is broadly transcribed in the first stage of development and silenced in most cells of an adult organism; it appears again in several tumors where, through different molecular mediators, promotes cell proliferation, motility and metastases. LncH19 has been associated with hypoxia-inducible factor 1-alpha (HIF-1α) activation and, in some tumors, it has proved to be necessary and required to sustain hypoxic responses. Here we propose to investigate a putative role for the lncH19 in hypoxia induced multiple myeloma (MM) progression. Transcriptional analysis of MM cell lines (RPMI and MM1.S) exposed to normoxia or hypoxia (1% O2) was done in order to evaluate lncH19 levels under hypoxic stimulation. Then, to investigate the role of lncH19 in hypoxia mediated MM progression, transcriptional, protein and functional assays have been performed on hypoxia stimulated MM cell lines, silenced or not for lncH19. Our data demonstrated that hypoxic stimulation in MM cell lines induced the overexpression of lncH19, which, in turn, is required for the expression of the hypoxia induced genes involved in MM dissemination, such as C-X-C Motif Chemokine Receptor 4 (CXCR4) and Snail. Moreover, adhesion assays demonstrated that lncH19 silencing abrogates the increased adhesion on stromal cells induced by the hypoxic condition. Finally, Western blot analysis indicated that lncH19 silencing impaired HIF1α nuclear translocation. The LncH19, required for the induction of hypoxic responses in MM cells, could represent a new therapeutic target for MM. Full article
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Open AccessArticle
Mitochondrial Dysfunction in Skeletal Muscle of a Fibromyalgia Model: The Potential Benefits of Melatonin
Int. J. Mol. Sci. 2019, 20(3), 765; https://doi.org/10.3390/ijms20030765 - 11 Feb 2019
Cited by 5
Abstract
Fibromyalgia syndrome (FMS) is considered a musculoskeletal disorder associated to other symptoms including chronic pain. Since the hypothesis of FMS etiogenesis is consistent with mitochondrial dysfunction and oxidative stress, we evaluated the pathophysiological correlation among these factors studying some proteins involved in the [...] Read more.
Fibromyalgia syndrome (FMS) is considered a musculoskeletal disorder associated to other symptoms including chronic pain. Since the hypothesis of FMS etiogenesis is consistent with mitochondrial dysfunction and oxidative stress, we evaluated the pathophysiological correlation among these factors studying some proteins involved in the mitochondrial homeostasis. We focused our attention on the roles of peroxisome proliferator activated receptor gamma coactivator-1alpha (PGC-1α), mitofusin2 (Mfn2), and coenzyme Q10 (CoQ10) in reserpine-induced myalgic (RIM) rats that manifest fibromyalgia-like chronic pain symptoms. First, we underlined that RIM rats are a good model for studying the pathophysiology of FMS and moreover, we found that PGC-1α, Mfn2, and CoQ10 are involved in FMS. In fact, their expressions were reduced in gastrocnemius muscle determining an incorrect mitochondrial homeostasis. Today, none of the currently available drugs are fully effective against the symptoms of this disease and they, often, induce several adverse events; hence, many scientists have taken on the challenge of searching for non-pharmacological treatments. Another goal of this study was therefore the evaluation of the potential benefits of melatonin, an endogenous indoleamine having several functions including its potent capacity to induce antioxidant enzymes and to determine the protective or reparative mechanisms in the cells. We observed that melatonin supplementation significantly preserved all the studied parameters, counteracting oxidative stress in RIM rats and confirming that this indoleamine should be taken in consideration for improving health and/or counteract mitochondrial related diseases. Full article
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Planned Papers

The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.

Title: Are cancer stems cells restricted to just a single cell lineage?
Authors: Geoffrey Brown1 and Isidro Sánchez-García2,3

1 Institute of Clinical Sciences, University of Birmingham, UK; 2Experimental Therapeutics and Translational Oncology Program, Instituto de Biología Molecular y Celular del Cáncer, CSIC/Universidad de Salamanca; 3Institute of Biomedical Research of Salamanca (IBSAL), Salamanca, Spain

Abstract: The cancer stem cell theory, which states that most if not all cancers arise from a stem cell, revolutionised the way we view cancer. Just as for normal cell development, cancer cells are a hierarchy of cells. The elegant studies of twins that both develop childhood acute lymphoblastic leukaemia revealed that at least two genomic insults are required for cancer. They, or more, ‘hits’ do not appear to confer a growth advantage to cancer cells, nor do cancer cells appear to be better equipped to survive than normal cells. Cancer cells in general and created by a specific genomic insult generally belong to just one cell lineage. In keeping with this and for example, transgenic mice in which the LMO2 (associated to human T-acute lymphoblastic leukaemia) and BCR-ABLp210 (associated to human chronic myeloid leukaemia) oncogenes were active solely within the haematopoietic stem cell compartment developed T lymphocyte and neutrophil lineage-restricted leukaemias respectively, typifying the human diseases. This ‘hard-wiring’ of lineage affiliation, either throughout leukaemia stem cell development or at a particular stage, is different to the behaviour of the normal haematopoietic stem cell. Whilst these cells can commit directly to a developmental pathway, they remain versatile and can still choose to develop towards an end cell type that is different from their initial commitment. We think that cancer stem cells do not have this versatility and that this is an essential difference between normal and cancer stem cells. Here we review the findings that support this notion.

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