12 pages, 404 KiB  
Article
miR-29 Represses the Activities of DNA Methyltransferases and DNA Demethylases
by Sumiyo Morita 1, Takuro Horii 1, Mika Kimura 1, Takahiro Ochiya 2, Shoji Tajima 3 and Izuho Hatada 1,*
1 Laboratory of Genome Science, Biosignal Genome Resource Center, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan
2 Division of Molecular and Cellular Medicine, National Cancer Center Research Institute, 5-1-1, Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
3 Laboratory of Epigenetics, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
Int. J. Mol. Sci. 2013, 14(7), 14647-14658; https://doi.org/10.3390/ijms140714647 - 12 Jul 2013
Cited by 121 | Viewed by 11626
Abstract
Members of the microRNA-29 (miR-29) family directly target the DNA methyltransferases, DNMT3A and DNMT3B. Disturbances in the expression levels of miR-29 have been linked to tumorigenesis and tumor aggressiveness. Members of the miR-29 family are currently thought to repress DNA methylation and suppress [...] Read more.
Members of the microRNA-29 (miR-29) family directly target the DNA methyltransferases, DNMT3A and DNMT3B. Disturbances in the expression levels of miR-29 have been linked to tumorigenesis and tumor aggressiveness. Members of the miR-29 family are currently thought to repress DNA methylation and suppress tumorigenesis by protecting against de novo methylation. Here, we report that members of the miR-29 family repress the activities of DNA methyltransferases and DNA demethylases, which have opposing roles in control of DNA methylation status. Members of the miR-29 family directly inhibited DNA methyltransferases and two major factors involved in DNA demethylation, namely tet methylcytosine dioxygenase 1 (TET1) and thymine DNA glycosylase (TDG). Overexpression of miR-29 upregulated the global DNA methylation level in some cancer cells and downregulated DNA methylation in other cancer cells, suggesting that miR-29 suppresses tumorigenesis by protecting against changes in the existing DNA methylation status rather than by preventing de novo methylation of DNA. Full article
(This article belongs to the Special Issue Advances in Cancer Diagnosis)
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27 pages, 493 KiB  
Review
The Potential Role of Lycopene for the Prevention and Therapy of Prostate Cancer: From Molecular Mechanisms to Clinical Evidence
by Nina Pauline Holzapfel 1, Boris Michael Holzapfel 1, Simon Champ 2, Jesper Feldthusen 2, Judith Clements 3 and Dietmar Werner Hutmacher 1,4,5,*
1 Regenerative Medicine, Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove, QLD 4059, Brisbane, Australia
2 Human Nutrition, BASF SE, G-ENH/MB, 68623 Lampertheim, Germany
3 Australian Prostate Cancer Research Centre, Translational Research Institute, 37 Kent Street, Woolongabba, QLD 4102, Brisbane, Australia
4 The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive Northwest, Atlanta, GA 30332, USA
5 Institute of Advanced Study, Technical University of Munich, Lichtenbergstr. 2a, 85748 Garching, Munich, Germany
Int. J. Mol. Sci. 2013, 14(7), 14620-14646; https://doi.org/10.3390/ijms140714620 - 12 Jul 2013
Cited by 151 | Viewed by 19416
Abstract
Lycopene is a phytochemical that belongs to a group of pigments known as carotenoids. It is red, lipophilic and naturally occurring in many fruits and vegetables, with tomatoes and tomato-based products containing the highest concentrations of bioavailable lycopene. Several epidemiological studies have linked [...] Read more.
Lycopene is a phytochemical that belongs to a group of pigments known as carotenoids. It is red, lipophilic and naturally occurring in many fruits and vegetables, with tomatoes and tomato-based products containing the highest concentrations of bioavailable lycopene. Several epidemiological studies have linked increased lycopene consumption with decreased prostate cancer risk. These findings are supported by in vitro and in vivo experiments showing that lycopene not only enhances the antioxidant response of prostate cells, but that it is even able to inhibit proliferation, induce apoptosis and decrease the metastatic capacity of prostate cancer cells. However, there is still no clearly proven clinical evidence supporting the use of lycopene in the prevention or treatment of prostate cancer, due to the only limited number of published randomized clinical trials and the varying quality of existing studies. The scope of this article is to discuss the potential impact of lycopene on prostate cancer by giving an overview about its molecular mechanisms and clinical effects. Full article
(This article belongs to the Special Issue Molecular Research in Urology)
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13 pages, 864 KiB  
Article
Quorum Quenching in Culturable Phyllosphere Bacteria from Tobacco
by Anzhou Ma 1,†, Di Lv 2,†, Xuliang Zhuang 1 and Guoqiang Zhuang 1,*
1 Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
2 Insitute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
† These authors contributed equally to this work.
Int. J. Mol. Sci. 2013, 14(7), 14607-14619; https://doi.org/10.3390/ijms140714607 - 12 Jul 2013
Cited by 44 | Viewed by 9200
Abstract
Many Gram-negative plant pathogenic bacteria employ a N-acylhomoserine lactone (AHL)-based quorum sensing (QS) system to regulate their virulence traits. A sustainable biocontrol strategy has been developed using quorum quenching (QQ) bacteria to interfere with QS and protect plants from pathogens. Here, the [...] Read more.
Many Gram-negative plant pathogenic bacteria employ a N-acylhomoserine lactone (AHL)-based quorum sensing (QS) system to regulate their virulence traits. A sustainable biocontrol strategy has been developed using quorum quenching (QQ) bacteria to interfere with QS and protect plants from pathogens. Here, the prevalence and the diversity of QQ strains inhabiting tobacco leaf surfaces were explored. A total of 1177 leaf-associated isolates were screened for their ability to disrupt AHL-mediated QS, using the biosensor Chromobacterium violaceum CV026. One hundred and sixty-eight strains (14%) are capable of interfering with AHL activity. Among these, 106 strains (63%) of the culturable quenchers can enzymatically degrade AHL molecules, while the remaining strains might use other QS inhibitors to interrupt the chemical communication. Moreover, almost 79% of the QQ strains capable of inactivating AHLs enzymatically have lactonase activity. Further phylogenetic analysis based on 16S rDNA revealed that the leaf-associated QQ bacteria can be classified as Bacillus sp., Acinetobacter sp., Lysinibacillus sp., Serratia sp., Pseudomonas sp., and Myroides sp. The naturally occurring diversity of bacterial quenchers might provide opportunities to use them as effective biocontrol reagents for suppressing plant pathogen in situ. Full article
(This article belongs to the Special Issue Quorum Sensing Research in Microbial Systems)
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13 pages, 1483 KiB  
Article
Integrated Self-Assembly of the Mms6 Magnetosome Protein to Form an Iron-Responsive Structure
by Shuren Feng 1,2, Lijun Wang 1,2,†, Pierre Palo 1, Xunpei Liu 1,3, Surya K. Mallapragada 1,3 and Marit Nilsen-Hamilton 1,2,*
1 Ames National Laboratory, Ames, IA 50011, USA
2 Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA
3 Department of Chemical and Biological Engineering, Iowa State University, Ames, IA 50011, USA
† Current address: National Center for Protein Science Shanghai, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 333 Haike Road, Shanghai 201203, China;
Int. J. Mol. Sci. 2013, 14(7), 14594-14606; https://doi.org/10.3390/ijms140714594 - 12 Jul 2013
Cited by 29 | Viewed by 9742
Abstract
A common feature of biomineralization proteins is their self-assembly to produce a surface consistent in size with the inorganic crystals that they produce. Mms6, a small protein of 60 amino acids from Magnetospirillum magneticum strain AMB-1 that promotes the in vitro growth of [...] Read more.
A common feature of biomineralization proteins is their self-assembly to produce a surface consistent in size with the inorganic crystals that they produce. Mms6, a small protein of 60 amino acids from Magnetospirillum magneticum strain AMB-1 that promotes the in vitro growth of superparamagnetic magnetite nanocrystals, assembles in aqueous solution to form spherical micelles that could be visualized by TEM and AFM. The results reported here are consistent with the view that the N and C-terminal domains interact with each other within one polypeptide chain and across protein units in the assembly. From studies to determine the amino acid residues important for self-assembly, we identified the unique GL repeat in the N-terminal domain with additional contributions from amino acids in other positions, throughout the molecule. Analysis by CD spectroscopy identified a structural change in the iron-binding C-terminal domain in the presence of Fe3+. A change in the intrinsic fluorescence of tryptophan in the N-terminal domain showed that this structural change is transmitted through the protein. Thus, self-assembly of Mms6 involves an interlaced structure of intra- and inter-molecular interactions that results in a coordinated structural change in the protein assembly with iron binding. Full article
(This article belongs to the Special Issue Molecular Self-Assembly 2012)
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19 pages, 266 KiB  
Review
Melatonin in Alzheimer’s Disease
by Li Lin 1,2,†, Qiong-Xia Huang 3,†, Shu-Sheng Yang 2, Jiang Chu 1, Jian-Zhi Wang 1,* and Qing Tian 1,*
1 Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Department of Pathology and Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
2 Department of Pathology and Pathophysiology, College of Medical Science, Jishou University, 120 People Road, Jishou 436100, China
3 Department of TCM Rationale, College of Basic Medicine, Hubei University of Chinese Medicine, 1 West Road Huangjia Lake, Wuhan 430065, China
† These authors contributed equally to this work.
Int. J. Mol. Sci. 2013, 14(7), 14575-14593; https://doi.org/10.3390/ijms140714575 - 12 Jul 2013
Cited by 188 | Viewed by 22843
Abstract
Alzheimer’s disease (AD), an age-related neurodegenerative disorder with progressive cognition deficit, is characterized by extracellular senile plaques (SP) of aggregated β-amyloid (Aβ) and intracellular neurofibrillary tangles, mainly containing the hyperphosphorylated microtubule-associated protein tau. Multiple factors contribute to the etiology of AD in terms [...] Read more.
Alzheimer’s disease (AD), an age-related neurodegenerative disorder with progressive cognition deficit, is characterized by extracellular senile plaques (SP) of aggregated β-amyloid (Aβ) and intracellular neurofibrillary tangles, mainly containing the hyperphosphorylated microtubule-associated protein tau. Multiple factors contribute to the etiology of AD in terms of initiation and progression. Melatonin is an endogenously produced hormone in the brain and decreases during aging and in patients with AD. Data from clinical trials indicate that melatonin supplementation improves sleep, ameliorates sundowning and slows down the progression of cognitive impairment in AD patients. Melatonin efficiently protects neuronal cells from Aβ-mediated toxicity via antioxidant and anti-amyloid properties. It not only inhibits Aβ generation, but also arrests the formation of amyloid fibrils by a structure-dependent interaction with Aβ. Our studies have demonstrated that melatonin efficiently attenuates Alzheimer-like tau hyperphosphorylation. Although the exact mechanism is still not fully understood, a direct regulatory influence of melatonin on the activities of protein kinases and protein phosphatases is proposed. Additionally, melatonin also plays a role in protecting the cholinergic system and in anti-inflammation. The aim of this review is to stimulate interest in melatonin as a potentially useful agent in the prevention and treatment of AD. Full article
(This article belongs to the Section Biochemistry)
25 pages, 2873 KiB  
Article
Chemical and Colloidal Stability of Carboxylated Core-Shell Magnetite Nanoparticles Designed for Biomedical Applications
by Márta Szekeres 1,*, Ildikó Y. Tóth 1, Erzsébet Illés 1, Angéla Hajdú 2, István Zupkó 3, Katalin Farkas 4, Gábor Oszlánczi 5, László Tiszlavicz 6 and Etelka Tombácz 1,*
1 Department of Physical Chemistry and Materials Science, University of Szeged, Aradi Vt. 1, H-6720 Szeged, Hungary
2 Laboratory of Nanochemistry, Department of Biophysics and Radiation Biology, Semmelweis University, H-1089 Budapest, Nagyvárad tér 4, Hungary
3 Department of Pharmacodynamics and Biopharmacy, University of Szeged, Eötvös u. 1, H-6720 Szeged, Hungary
4 Department of Laboratory Medicine, University of Szeged, Semmelweis u. 6, H-6720 Szeged, Hungary
5 Department of Public Health, University of Szeged, Dóm tér 10, H-6720 Szeged, Hungary
6 Department of Pathology, University of Szeged, Állomás u. 2, H-6720 Szeged, Hungary
Int. J. Mol. Sci. 2013, 14(7), 14550-14574; https://doi.org/10.3390/ijms140714550 - 12 Jul 2013
Cited by 78 | Viewed by 11966
Abstract
Despite the large efforts to prepare super paramagnetic iron oxide nanoparticles (MNPs) for biomedical applications, the number of FDA or EMA approved formulations is few. It is not known commonly that the approved formulations in many instances have already been withdrawn or discontinued [...] Read more.
Despite the large efforts to prepare super paramagnetic iron oxide nanoparticles (MNPs) for biomedical applications, the number of FDA or EMA approved formulations is few. It is not known commonly that the approved formulations in many instances have already been withdrawn or discontinued by the producers; at present, hardly any approved formulations are produced and marketed. Literature survey reveals that there is a lack for a commonly accepted physicochemical practice in designing and qualifying formulations before they enter in vitro and in vivo biological testing. Such a standard procedure would exclude inadequate formulations from clinical trials thus improving their outcome. Here we present a straightforward route to assess eligibility of carboxylated MNPs for biomedical tests applied for a series of our core-shell products, i.e., citric acid, gallic acid, poly(acrylic acid) and poly(acrylic acid-co-maleic acid) coated MNPs. The discussion is based on physicochemical studies (carboxylate adsorption/desorption, FTIR-ATR, iron dissolution, zeta potential, particle size, coagulation kinetics and magnetization measurements) and involves in vitro and in vivo tests. Our procedure can serve as an example to construct adequate physico-chemical selection strategies for preparation of other types of core-shell nanoparticles as well. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles 2013)
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18 pages, 1818 KiB  
Article
Membrane Binding and Insertion of a pHLIP Peptide Studied by All-Atom Molecular Dynamics Simulations
by Yonghua Deng 1, Zhenyu Qian 1, Yin Luo 1, Yun Zhang 1, Yuguang Mu 2 and Guanghong Wei 1,*
1 State Key Laboratory of Surface Physics, Key Laboratory for Computational Physical Sciences (Ministry of Education), and Department of Physics, Fudan University, 220 Handan Road, Shanghai 200433, China
2 School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
Int. J. Mol. Sci. 2013, 14(7), 14532-14549; https://doi.org/10.3390/ijms140714532 - 12 Jul 2013
Cited by 15 | Viewed by 8310
Abstract
Recent experiments in function mechanism study reported that a pH low-insertion peptide (pHLIP) can insert into a zwitterionic palmitoyloleoylphosphatidylcholine (POPC) lipid bilayer at acidic pH while binding to the bilayer surface at basic pH. However, the atomic details of the pH-dependent interaction of [...] Read more.
Recent experiments in function mechanism study reported that a pH low-insertion peptide (pHLIP) can insert into a zwitterionic palmitoyloleoylphosphatidylcholine (POPC) lipid bilayer at acidic pH while binding to the bilayer surface at basic pH. However, the atomic details of the pH-dependent interaction of pHLIP with a POPC bilayer are not well understood. In this study, we investigate the detailed interactions of pHLIP with a POPC bilayer at acidic and basic pH conditions as those used in function mechanism study, using all-atom molecular dynamics (MD) simulations. Simulations have been performed by employing the initial configurations, where pHLIP is placed in aqueous solution, parallel to bilayer surface (system S), partially-inserted (system P), or fully-inserted (system F) in POPC bilayers. On the basis of multiple 200-ns MD simulations, we found (1) pHLIP in system S can spontaneously insert into a POPC bilayer at acidic pH, while binding to the membrane surface at basic pH; (2) pHLIP in system P can insert deep into a POPC bilayer at acidic pH, while it has a tendency to exit, and stays at bilayer surface at basic pH; (3) pHLIP in system F keeps in an α-helical structure at acidic pH while partially unfolding at basic pH. This study provides at atomic-level the pH-induced insertion of pHLIP into POPC bilayer. Full article
(This article belongs to the Special Issue Computational Modelling of Biological Membranes)
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14 pages, 589 KiB  
Review
Exploiting CRISPR/Cas: Interference Mechanisms and Applications
by Hagen Richter, Lennart Randau and André Plagens *
Prokaryotic Small RNA Biology, Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Straße 10, 35043 Marburg, Germany
Int. J. Mol. Sci. 2013, 14(7), 14518-14531; https://doi.org/10.3390/ijms140714518 - 12 Jul 2013
Cited by 32 | Viewed by 16966
Abstract
The discovery of biological concepts can often provide a framework for the development of novel molecular tools, which can help us to further understand and manipulate life. One recent example is the elucidation of the prokaryotic adaptive immune system, clustered regularly interspaced short [...] Read more.
The discovery of biological concepts can often provide a framework for the development of novel molecular tools, which can help us to further understand and manipulate life. One recent example is the elucidation of the prokaryotic adaptive immune system, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) that protects bacteria and archaea against viruses or conjugative plasmids. The immunity is based on small RNA molecules that are incorporated into versatile multi-domain proteins or protein complexes and specifically target viral nucleic acids via base complementarity. CRISPR/Cas interference machines are utilized to develop novel genome editing tools for different organisms. Here, we will review the latest progress in the elucidation and application of prokaryotic CRISPR/Cas systems and discuss possible future approaches to exploit the potential of these interference machineries. Full article
(This article belongs to the Special Issue Regulation by non-coding RNAs 2013)
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14 pages, 1252 KiB  
Article
Uterine Micro-Environment and Estrogen-Dependent Regulation of Osteopontin Expression in Mouse Blastocyst
by Qing-Zhen Xie 1,*,†, Qian-Rong Qi 1,†, Ying-Xian Chen 1,2, Wang-Ming Xu 1, Qian Liu 1 and Jing Yang 1
1 Center for Reproductive Medicine, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei, China
2 Department of Obstetrics and Gynecology, Taihe Hospital, Shiyan 441000, Hubei, China
† These authors contributed equally to this work.
Int. J. Mol. Sci. 2013, 14(7), 14504-14517; https://doi.org/10.3390/ijms140714504 - 11 Jul 2013
Cited by 14 | Viewed by 7436
Abstract
Embryo implantation is a highly synchronized bioprocess between an activated blastocyst and a receptive uterus. In mice, successful implantation relies on the dynamic interplay of estrogen and progesterone; however, the key mediators downstream of these hormones that act on blastocyst competency and endometrium [...] Read more.
Embryo implantation is a highly synchronized bioprocess between an activated blastocyst and a receptive uterus. In mice, successful implantation relies on the dynamic interplay of estrogen and progesterone; however, the key mediators downstream of these hormones that act on blastocyst competency and endometrium receptivity acquisition are largely unknown. In this study, we showed that the expression of osteopontin (OPN) in mouse blastocysts is regulated by ovarian estrogen and uterine micro-environment. OPN mRNA is up-regulated in mouse blastocyst on day 4 of pregnancy, which is associated with ovarian estrogen secretion peak. Hormone treatment in vivo demonstrated that OPN expression in a blastocyst is regulated by estrogen through an estrogen receptor (ER). Our results of the delayed and activated implantation model showed that OPN expression is induced after estrogen injection. While estrogen treatment during embryo culture in vitro showed less effect on OPN expression, the tubal ligation model on day 3 of pregnancy confirmed that the regulation of estrogen on OPN expression in blastocyst might, through some specific cytokines, have existed in a uterine micro-environment. Collectively, our study presents that estrogen regulates OPN expression and it may play an important role during embryo implantation by activating blastocyst competence and facilitating the endometrium acceptable for active blastocyst. Full article
(This article belongs to the Section Biochemistry)
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29 pages, 3686 KiB  
Review
Membrane Trafficking of Death Receptors: Implications on Signalling
by Wulf Schneider-Brachert, Ulrike Heigl and Martin Ehrenschwender *
Institute for Clinical Microbiology and Hygiene, University of Regensburg, Franz-Josef-Strauss-Allee 11, Regensburg 93053, Germany
Int. J. Mol. Sci. 2013, 14(7), 14475-14503; https://doi.org/10.3390/ijms140714475 - 11 Jul 2013
Cited by 47 | Viewed by 11286
Abstract
Death receptors were initially recognised as potent inducers of apoptotic cell death and soon ambitious attempts were made to exploit selective ignition of controlled cellular suicide as therapeutic strategy in malignant diseases. However, the complexity of death receptor signalling has increased substantially during [...] Read more.
Death receptors were initially recognised as potent inducers of apoptotic cell death and soon ambitious attempts were made to exploit selective ignition of controlled cellular suicide as therapeutic strategy in malignant diseases. However, the complexity of death receptor signalling has increased substantially during recent years. Beyond activation of the apoptotic cascade, involvement in a variety of cellular processes including inflammation, proliferation and immune response was recognised. Mechanistically, these findings raised the question how multipurpose receptors can ensure selective activation of a particular pathway. A growing body of evidence points to an elegant spatiotemporal regulation of composition and assembly of the receptor-associated signalling complex. Upon ligand binding, receptor recruitment in specialized membrane compartments, formation of receptor-ligand clusters and internalisation processes constitute key regulatory elements. In this review, we will summarise the current concepts of death receptor trafficking and its implications on receptor-associated signalling events. Full article
(This article belongs to the Special Issue Regulation of Membrane Trafficking and Its Potential Implications)
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15 pages, 5943 KiB  
Article
Cultivation of Keratinocytes and Fibroblasts in a Three-Dimensional Bovine Collagen-Elastin Matrix (Matriderm®) and Application for Full Thickness Wound Coverage in Vivo
by Jasper Killat, Kerstin Reimers, Claudia Y. Choi, Sabrina Jahn, Peter M. Vogt and Christine Radtke *
Department of Plastic, Hand- and Reconstructive Surgery, Hannover Medical School, Hannover D-30659, Germany
Int. J. Mol. Sci. 2013, 14(7), 14460-14474; https://doi.org/10.3390/ijms140714460 - 11 Jul 2013
Cited by 45 | Viewed by 10666
Abstract
New skin substitutes for burn medicine or reconstructive surgery pose an important issue in plastic surgery. Matriderm® is a clinically approved three-dimensional bovine collagen-elastin matrix which is already used as a dermal substitute of full thickness burn wounds. The drawback of an [...] Read more.
New skin substitutes for burn medicine or reconstructive surgery pose an important issue in plastic surgery. Matriderm® is a clinically approved three-dimensional bovine collagen-elastin matrix which is already used as a dermal substitute of full thickness burn wounds. The drawback of an avital matrix is the limited integration in full thickness skin defects, depending on the defect size. To further optimize this process, Matriderm® has also been studied as a matrix for tissue engineering of skin albeit long-term cultivation of the matrix with cells has been difficult. Cells have generally been seeded onto the matrix with high cell loss and minimal time-consuming migration. Here we developed a cell seeded skin equivalent after microtransfer of cells directly into the matrix. First, cells were cultured, and microinjected into Matriderm®. Then, cell viability in the matrix was determined by histology in vitro. As a next step, the skin substitute was applied in vivo into a full thickness rodent wound model. The wound coverage and healing was observed over a period of two weeks followed by histological examination assessing cell viability, proliferation and integration into the host. Viable and proliferating cells could be found throughout the entire matrix. The presented skin substitute resembles healthy skin in morphology and integrity. Based on this study, future investigations are planned to examine behaviour of epidermal stem cells injected into a collagen-elastin matrix under the aspects of establishment of stem cell niches and differentiation. Full article
(This article belongs to the Special Issue Molecular Research of Epidermal Stem Cells)
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21 pages, 3569 KiB  
Article
Upregulation of Phosphorylated HSP27, PRDX2, GRP75, GRP78 and GRP94 in Acquired Middle Ear Cholesteatoma Growth
by Kuen Yao Ho 1,2, Tai Sheng Yeh 3,†, Han Hsiang Huang 4,†, Kuo Feng Hung 5,†, Chee Yin Chai 6,7, Wan Tzu Chen 6, Shih Meng Tsai 8, Ning Chia Chang 9, Chen Yu Chien 1, Hsun Mo Wang 10 and Yu Jen Wu 4,*
1 Department of Otorhinolaryngology, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan
2 Department of Otorhinolaryngology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80756,Taiwan
3 Department of Food Science and Nutrition, Meiho University, Pingtung 91202, Taiwan
4 Department of Beauty Science, Meiho University, Pingtung 91202, Taiwan
5 Graduate Institute of Applied Health and Biotechnology, Meiho University, Pingtung 91202, Taiwan
6 Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan
7 Department of Pathology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80756, Taiwan
8 Department of Public Health, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80756, Taiwan
9 Department of Preventive Medicine, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan
10 Department of Otorhinolaryngology, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung Medical University, Kaohsiung 80756, Taiwan
† The authors contributed equally to this work.
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Int. J. Mol. Sci. 2013, 14(7), 14439-14459; https://doi.org/10.3390/ijms140714439 - 11 Jul 2013
Cited by 13 | Viewed by 8729
Abstract
Cholesteatoma is a destructive and expanding growth of keratinizing squamous epithelium in the middle ear or petrous apex. The molecular and cellular processes of the pathogenesis of acquired middle ear cholesteatoma have not been fully understood. In this study, comparative proteomic analysis was [...] Read more.
Cholesteatoma is a destructive and expanding growth of keratinizing squamous epithelium in the middle ear or petrous apex. The molecular and cellular processes of the pathogenesis of acquired middle ear cholesteatoma have not been fully understood. In this study, comparative proteomic analysis was conducted to investigate the roles of specific proteins in the pathways regarding keratinocyte proliferation in cholesteatoma. The differential proteins were detected by comparing the two-dimension electrophoresis (2-DE) maps of the epithelial tissues of 12 attic cholesteatomas with those of retroauricular skins. There were 14 upregulated proteins in the epithelial tissues of cholesteatoma in comparison with retroauricular skin. The modulation of five crucial proteins, HSP27, PRDX2, GRP75, GRP78 and GRP94, was further determined by RT-PCR, Western blot and immunohistochemistry. Phosphorylation of HSP27 at Ser-82 was identified by mass spectroscopy. The results of this study suggested that phosphorylated HSP27 is the end expression of two potential signal-transduction pathways, and together with PRDX2, they are very likely involved in the proliferation of keratinocytes in cholesteatoma. Upregulations of GRP75, GRP78 and GRP94 in keratinocytes may be able to counter endoplasmic reticulum stress, to inhibit cell apoptosis, to prevent protein unfolding and to promote cholesteatoma growth. Full article
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13 pages, 251 KiB  
Article
Functional Expression of Thyroid-Stimulating Hormone Receptor on Nano-Sized Bacterial Magnetic Particles in Magnetospirillum magneticum AMB-1
by Yasuhiro Sugamata, Ryo Uchiyama, Toru Honda, Tsuyoshi Tanaka, Tadashi Matsunaga and Tomoko Yoshino *
Division of Biotechnology and Life Science, Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16, Naka-cho, Koganei, Tokyo 184-8588, Japan
Int. J. Mol. Sci. 2013, 14(7), 14426-14438; https://doi.org/10.3390/ijms140714426 - 11 Jul 2013
Cited by 14 | Viewed by 8111
Abstract
The measurement of autoantibodies to thyroid-stimulating hormone receptor (TSHR) is important for the diagnosis of autoimmune thyroid disease such as Graves’ disease (GD). Although TSHR from porcine thyroid membrane is commonly used for the measurement of TSHR autoantibodies (TRAb), recombinant human TSHR (hTSHR) [...] Read more.
The measurement of autoantibodies to thyroid-stimulating hormone receptor (TSHR) is important for the diagnosis of autoimmune thyroid disease such as Graves’ disease (GD). Although TSHR from porcine thyroid membrane is commonly used for the measurement of TSHR autoantibodies (TRAb), recombinant human TSHR (hTSHR) remains ideal in terms of stable supply and species identity. Here we set out to express recombinant hTSHR on the lipid-bilayer surface of magnetic nanoparticles from a magnetotactic bacterium, Magnetospirillum magneticum AMB-1. Using a tetracycline-inducible expression system, we successfully overexpressed functional hTSHR on bacterial magnetic particles (BacMPs) in AMB-1 via an anchor protein specific for BacMPs. The overexpressed hTSHR was membrane integrated and possessed both ligand and autoantibody binding activity. Our data suggest that hTSHR-displayed BacMPs have potential as novel tools for ligand-receptor interaction analysis or for TRAb immunoassay in GD patients. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles 2013)
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18 pages, 1160 KiB  
Article
Dependence of Interaction Free Energy between Solutes on an External Electrostatic Field
by Pei-Kun Yang
Department of Biomedical Engineering, I-SHOU University, Kaohsiung 84001, Taiwan
Int. J. Mol. Sci. 2013, 14(7), 14408-14425; https://doi.org/10.3390/ijms140714408 - 11 Jul 2013
Cited by 8 | Viewed by 5917
Abstract
To explore the athermal effect of an external electrostatic field on the stabilities of protein conformations and the binding affinities of protein-protein/ligand interactions, the dependences of the polar and hydrophobic interactions on the external electrostatic field, −Eext, were studied using [...] Read more.
To explore the athermal effect of an external electrostatic field on the stabilities of protein conformations and the binding affinities of protein-protein/ligand interactions, the dependences of the polar and hydrophobic interactions on the external electrostatic field, −Eext, were studied using molecular dynamics (MD) simulations. By decomposing Eext into, along, and perpendicular to the direction formed by the two solutes, the effect of Eext on the interactions between these two solutes can be estimated based on the effects from these two components. Eext was applied along the direction of the electric dipole formed by two solutes with opposite charges. The attractive interaction free energy between these two solutes decreased for solutes treated as point charges. In contrast, the attractive interaction free energy between these two solutes increased, as observed by MD simulations, for Eext = 40 or 60 MV/cm. Eext was applied perpendicular to the direction of the electric dipole formed by these two solutes. The attractive interaction free energy was increased for Eext = 100 MV/cm as a result of dielectric saturation. The force on the solutes along the direction of Eext computed from MD simulations was greater than that estimated from a continuum solvent in which the solutes were treated as point charges. To explore the hydrophobic interactions, Eext was applied to a water cluster containing two neutral solutes. The repulsive force between these solutes was decreased/increased for Eext along/perpendicular to the direction of the electric dipole formed by these two solutes. Full article
(This article belongs to the Special Issue Proteins and Protein-Ligand Interactions)
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13 pages, 379 KiB  
Article
Synergistic Effects of Nano-Sized Titanium Dioxide and Zinc on the Photosynthetic Capacity and Survival of Anabaena sp.
by Yulin Tang *, Shuyan Li, Junlian Qiao, Hongtao Wang and Lei Li
State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
Int. J. Mol. Sci. 2013, 14(7), 14395-14407; https://doi.org/10.3390/ijms140714395 - 11 Jul 2013
Cited by 53 | Viewed by 8284
Abstract
Anabaena sp. was used to examine the toxicity of exposure to a nano-TiO2 suspension, Zn2+ solution, and mixtures of nano-TiO2 and Zn2+ suspensions. Typical chlorophyll fluorescence parameters, including effective quantum yield, photosynthetic efficiency and maximal electron transport rate, were [...] Read more.
Anabaena sp. was used to examine the toxicity of exposure to a nano-TiO2 suspension, Zn2+ solution, and mixtures of nano-TiO2 and Zn2+ suspensions. Typical chlorophyll fluorescence parameters, including effective quantum yield, photosynthetic efficiency and maximal electron transport rate, were measured by a pulse-amplitude modulated fluorometer. Nano-TiO2 particles exhibited no significant toxicity at concentrations lower than 10.0 mg/L. The 96 h concentration for the 50% maximal effect (EC50) of Zn2+ alone to Anabaena sp. was 0.38 ± 0.004 mg/L. The presence of nano-TiO2 at low concentrations (<1.0 mg/L) significantly enhanced the toxicity of Zn2+ and consequently reduced the EC50 value to 0.29 ± 0.003 mg/L. However, the toxicity of the Zn2+/TiO2 system decreased with increasing nano-TiO2 concentration because of the substantial adsorption of Zn2+ by nano-TiO2. The toxicity curve of the Zn2+/TiO2 system as a function of incremental nano-TiO2 concentrations was parabolic. The toxicity significantly increased at the initial stage, reached its maximum, and then decreased with increasing nano-TiO2 concentration. Hydrodynamic sizes, concentration of nano-TiO2 and Zn2+ loaded nano-TiO2 were the main parameters for synergistic toxicity. Full article
(This article belongs to the Special Issue Bioactive Nanoparticles 2013)
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