Search Results (39)

Excessive ammonia accumulation poses a significant threat to aquatic species. Potamocorbula ustulata, known for its burrowing behavior and high population density, may experience elevated ammonia levels in its environment. However, its ammonia stress response mechanisms remain unclear. This study investigates the physiological and molecular responses of P. ustulata to acute ammonia exposure. Antioxidant enzyme activity was significantly altered in the gills and hepatopancreas, with GS, GDH, and ARG levels markedly increasing in the hepatopancreas. Transcriptome analysis revealed that after 24 h of exposure, differentially expressed genes (DEGs) were enriched in apoptosis and inflammation-related pathways (MAPK, NF-kB, NOD-like receptor signaling). By 96 h, DEGs in the gills were associated with nitrogen metabolism and transport, while those in the hepatopancreas were linked to oxidative phosphorylation and amino acid metabolism. Key ammonia transport and excretion genes, including V-type H⁺-ATPase, Ammonium transporter Rh, and Na⁺/K⁺-ATPase, were significantly upregulated in the gills, while glutamine synthetase and glutamate dehydrogenase were upregulated in the hepatopancreas (p < 0.05). These findings suggest that ammonia stress disrupts antioxidant defense, triggers inflammation and apoptosis, and enhances ammonia tolerance through excretion, glutamine conversion, and urea synthesis. This study provides insights into the molecular mechanisms underlying ammonia tolerance in bivalves. Full article

Aegilops tauschii, a monocotyledonous annual grass, recognized as a pivotal progenitor of modern wheat (Triticum aestivum L.), serves as the D-genome donor in hexaploid wheat. This diploid species (2n = 2x = 14, DD) harbors a substantial reservoir of genetic diversity, particularly in terms of biotic and abiotic stress resistance traits. The extensive allelic variation present in its genome has been increasingly utilized for wheat genetic enhancement, particularly through introgression breeding programs aimed at improving yield potential and stress resilience. Heavy metal ATPases (HMAs), which belong to the P-type ATPase superfamily and are also known as P1B-type ATPases, play a crucial role in transporting heavy metals and maintaining metal ion homeostasis in plant cells. HMAs have been extensively studied in model plants like Arabidopsis thaliana and rice. However, this family has not been reported in A. tauschii. Here, we conducted the genome-wide identification and bioinformatics analysis of the AetHMA gene family in A. tauschii, resulting in the discovery of a total of nine AetHMA members. Among AetHMA genes, six pairs are large-block duplication genes, which mainly occur among the four genes of AetHMA2, AetHMA4, AetHMA8, and AetHMA9. Additionally, there is one pair that consists of tandem duplication genes (AetHMA6: AetHMA7). All AetHMAs can be classified into six groups (I–VI), which are further divided into two branches: the copper subclasses and the zinc subclasses. Initially, A. tauschii was grown in a 1/2 Hoagland nutrient solution and subsequently exposed to four heavy metals: zinc (Zn), copper (Cu), manganese (Mn), and cadmium (Cd). Following this treatment, the expression profiles of nine AetHMA genes were assessed. The results indicated that, under zinc and manganese stress, the HMA family members exhibited enhanced expression in the leaves, whereas the expression of most members in the roots was downregulated. In the roots, except for AetHMA2, AetHMA5, and AetHMA8, the expression levels of other members were upregulated in response to Cd exposure. Furthermore, AetHMA4 diminishes the tolerance of yeast to Mn by increasing the absorption of Mn, while AetHMA8 increases the tolerance of yeast to Cd by reducing the absorption of Cd. This study provides experimental data regarding the function of the AetHMA gene in the transport, regulation, and detoxification of heavy metal elements in A. tauschii. Full article

Background: Cuproptosis is a form of copper-dependent non-apoptotic cell death. Cancer cells that prefer to use aerobic glycolysis for energy generation are commonly insensitive to cuproptosis, which hinders its application for cancer treatment. Epigallocatechin gallate (EGCG) possesses diverse pharmacological activities. However, the association between EGCG and cuproptosis has not been studied. Methods: The cell viability, proliferation, and cuproptosis-related protein levels were detected to investigate whether EGCG enhances the sensitivity of HCC cells to cuproptosis. The intracellular copper level, related copper metabolism proteins, and gene expression were detected to explore the mechanisms. In addition, a nude mouse xenograft model was established to determine the effects of EGCG on cuproptosis in tumor tissues. Results: The combination of EGCG and copper ionophores significantly enhanced the mortality of HCC cells and heightened the sensitivity of HCC cells to cuproptosis. There was a notable reduction in the expression of copper export protein copper-transporting P-type ATPase (ATP7B). EGCG effectively suppressed metal regulatory transcription factor (MTF1) expression and subsequently hindered the transcriptional regulation of ATP7B. EGCG also facilitated the intratumoral accumulation of copper and augmented susceptibility to cuproptosis in vivo. Conclusions: EGCG can increase the sensitivity of hepatocellular carcinoma cells to cuproptosis by promoting intracellular copper accumulation through the MTF1/ATP7B axis. Full article

Two related P-type ATPases, designated as ATPase1 and ATPase3, were identified in Plasmodium falciparum. These two ATPases exhibit very similar gene and protein structures and are most similar to P5B-ATPases. There are some differences in the predicted substrate-binding sites of ATPase1 and ATPase3 that suggest different functions for these two ATPases. Orthologues of ATPase3 were identified in all Plasmodium species, including the related Hepatocystis and Haemoproteus. ATPase3 orthologues could also be identified in all apicomplexan species, but no clear orthologues were identified outside of the Apicomplexa. In contrast, ATPase1 orthologues were only found in the Laverania, avian Plasmodium species, and Haemoproteus. ATPase1 likely arose from a duplication of the ATPase3 gene early in the evolution of malaria parasites. These results support a model in which early malaria parasites split into two clades. One clade consists of mammalian malaria parasites and Hepatocystis but excludes P. falciparum and related Laverania. The other clade includes Haemoproteus, avian Plasmodium species, and Laverania. This contrasts to recent models that suggest all mammalian malaria parasites form a monophyletic group, and all avian malaria parasites form a separate monophyletic group. ATPase1 may be a useful taxonomic/phylogenetic character for the phylogeny of Haemosporidia. Full article

Background/Objectives: Wilson’s disease (WD) (OMIM 277900) or hepatolenticular degeneration is an autosomal recessive disorder caused by impaired copper excretion with subsequent accumulation in the liver, brain, and other tissues of the body. The defects in copper metabolism are based on various pathogenic variants of the ATP7B gene encoding copper-transporting P-type ATPase. The aim of this work is to search for pathogenic variants of the ATP7B gene among Eastern Eurasian patient cohorts and to pick correlations between pathogenic variants, gender, age of onset of the disease, and the course of the disease. Methods: The material for the study was the biomaterial of 100 people. The search for mutations was carried out by Sanger sequencing. Multiple alignment of nucleotide sequences and their analysis was performed using the MEGA-X software. To study the genotype-phenotypic correlation, an analysis of the medical records of each patient was carried out. Results: Most common pathogenic variant (48%) in the sample is p.His1069Gln (c.3207C>A), located in exon 14 of the ATP7B gene. Pathogenic variants of p.Glu1064Lys (c.3190G>A)—20%—and p.Met769HisfsTer26 (c.2304insC)—8%—of exons 14 and 8 were also common. For patients with pathogenic alleles p.His1069Gln (c.3207C>A) and p.Glu1064Lys (c.3190G>A), typical deviations are mental and neurological manifestations of WD. In patients with the pathogenic allele p.Met769HisfsTer26 (c.2304insC), deviations are more characteristic of the liver and a combination of various symptoms that are atypical for WD. Conclusions: In this study, we were able to obtain differences in symptoms in patients with different pathogenic alleles of the ATP7B gene. Full article

Wilson’s disease (WD) is an autosomal recessive disorder characterized by toxic accumulation of copper in the liver, brain, and other organs. The disease is caused by pathogenic variants in the ATP7B gene, which encodes a P-type copper transport ATPase. Diagnosing WD is associated with numerous difficulties due to the wide range of clinical manifestations and its unknown dependence on the physiological characteristics of the patient. This leads to a delay in the start of therapy and the subsequent deterioration of the patient’s condition. However, in recent years, molecular genetic testing of patients using next generation sequencing (NGS) has been gaining popularity. This immediately affected the detection speed of WD. If, previously, the frequency of this disease was estimated at 1:35,000–45,000 people, now, when conducting large molecular genetic studies, the frequency is calculated as 1:7026 people. This certainly points to the problem of identifying WD patients. This review provides an update on the performance of epidemiological studies of WD and describes normal physiological functions of the protein and diversified disfunctions depending on pathogenic variants of the ATP7B gene. Future prospects in the development of WD genetic diagnostics are also discussed. Full article

Parkinson’s disease (PD) stands as the most prevalent degenerative movement disorder, marked by the degeneration of dopaminergic neurons in the substantia nigra of the midbrain. In this study, we conducted a transcriptome analysis utilizing post mortem mRNA extracted from the substantia nigra of both PD patients and healthy control (CTRL) individuals. Specifically, we acquired eight samples from individuals with PD and six samples from CTRL individuals, with no discernible pathology detected in the latter group. RNA sequencing was conducted using the TapeStation 4200 system from Agilent Technologies. A total of 16,148 transcripts were identified, with 92 mRNAs displaying differential expression between the PD and control groups. Specifically, 33 mRNAs were significantly up-regulated, while 59 mRNAs were down-regulated in PD compared to the controls. The identification of statistically significant signaling pathways, with an adjusted p-value threshold of 0.05, unveiled noteworthy insights. Specifically, the enriched categories included cardiac muscle contraction (involving genes such as ATPase Na⁺/K⁺ transporting subunit beta 2 (ATP1B2), solute carrier family 8 member A1 (SLC8A1), and cytochrome c oxidase subunit II (COX2)), GABAergic synapse (involving GABA type A receptor-associated protein-like 1 (GABARAPL1), G protein subunit beta 5 (GNB5), and solute carrier family 38 member 2 (SLC38A2), autophagy (involving GABARAPL1 and tumor protein p53-inducible nuclear protein 2 (TP53INP2)), and Fc gamma receptor (FcγR) mediated phagocytosis (involving amphiphysin (AMPH)). These findings uncover new pathophysiological dimensions underlying PD, implicating genes associated with heart muscle contraction. This knowledge enhances diagnostic accuracy and contributes to the advancement of targeted therapies. Full article

The contamination of agricultural soil with cadmium (Cd), a heavy metal, poses a significant environmental challenge, affecting crop growth, development, and human health. Previous studies have established the pivotal role of the ZmHMA3 gene, a P-type ATPase heavy metal transporter, in determining variable Cd accumulation in maize grains among 513 inbred lines. To decipher the molecular mechanism underlying mutation-induced phenotypic differences mediated by ZmHMA3, we conducted a quantitative tandem mass tag (TMT)-based proteomic analysis of immature maize kernels. This analysis aimed to identify differentially expressed proteins (DEPs) in wild-type B73 and ZmHMA3 null mutant under Cd stress. The findings demonstrated that ZmHMA3 accumulated higher levels of Cd compared to B73 when exposed to varying Cd concentrations in the soil. In comparison to soil with a low Cd concentration, B73 and ZmHMA3 exhibited 75 and 142 DEPs, respectively, with 24 common DEPs shared between them. ZmHMA3 showed a higher induction of upregulated genes related to Cd stress than B73. Amino sugar and nucleotide sugar metabolism was specifically enriched in B73, while phenylpropanoid biosynthesis, nitrogen metabolism, and glyoxylate and dicarboxylate metabolism appeared to play a more significant role in ZmHMA3. This study provides proteomics insights into unraveling the molecular mechanism underlying the differences in Cd accumulation in maize kernels. Full article

Long-distance transport cadmium (Cd) from roots to shoots is a key factor for Cd phytoremediation. Our previous study indicated that heavy metal P_1B2-ATPases, IlHMA2, was involved in improving the accumulation of Cd via mediated long-distance transport Cd, contributing to the phytoremediation in Cd accumulator Iris lactea. However, whether the overexpression of IlHMA2 could enhance the accumulation and tolerance to Cd remains unclear in plants. Here, we generated transgenic tobacco overexpressing IlHMA2 and tested its effect on the translocation and accumulation of Cd and zinc (Zn), as well as the physio-biochemical characteristics under 50 mg/L Cd exposure. The overexpression of IlHMA2 significantly increased Cd concentrations in xylem saps, resulting in enhanced root-to-shoot Cd translocation compared with wild-type. Meanwhile, overexpressing IlHMA2 promoted Zn accumulations, accompanied by elevating proline contents and antioxidant enzyme activity (SOD, POD, and CAT) to diminish the overproduction of ROS in transgenic tobacco. These pieces of evidence suggested that higher Zn concentrations and lower ROS levels could tremendously alleviate Cd toxicity for transgenic tobacco, thereby improving the growth and tolerance. Overall, the overexpression of IlHMA2 could facilitate Cd accumulation and enhance its tolerance in tobacco exposed to Cd contaminations. This would provide a valuable reference for improving Cd phytoremediation efficiency. Full article

The heavy-metal-associated (HMA) proteins are a class of P_B1-type ATPases related to the intracellular transport and detoxification of metals. However, due to a lack of information regarding the HMA gene family in the Cucurbitaceae family, a comprehensive genome-wide analysis of the HMA family was performed in ten Cucurbitaceae species: Citrullus amarus, Citrullus colocynthis, Citrullus lanatus, Citrullus mucosospermus, Cucumis melo, Cucumis sativus, Cucurbita maxima, Cucurbita moschata, Cucurbita pepo, and Legenaria siceraria. We identified 103 Cucurbit HMA proteins with various members, ranging from 8 (Legenaria siceraria) to 14 (Cucurbita pepo) across species. The phylogenetic and structural analysis confirmed that the Cucurbitaceae HMA protein family could be further classified into two major clades: Zn/Co/Cd/Pb and Cu/Ag. The GO-annotation-based subcellular localization analysis predicted that all HMA gene family members were localized on membranes. Moreover, the analysis of conserved motifs and gene structure (intron/exon) revealed the functional divergence between clades. The interspecies microsynteny analysis demonstrated that maximum orthologous genes were found between species of the Citrullus genera. Finally, nine candidate HMA genes were selected, and their expression analysis was carried out via qRT-PCR in root, leaf, flower, and fruit tissues of C. pepo under arsenic stress. The expression pattern of the CpeHMA genes showed a distinct pattern of expression in root and shoot tissues, with a remarkable expression of CpeHMA6 and CpeHMA3 genes from the Cu/Ag clade. Overall, this study provides insights into the functional analysis of the HMA gene family in Cucurbitaceae species and lays down the basic knowledge to explore the role and mechanism of the HMA gene family to cope with arsenic stress conditions. Full article

The pollution of heavy metals is extremely serious in China, including zinc (Zn), copper (Cu), lead (Pb), and cadmium (Cd). Heavy-metal-transporting ATPase (HMA) belongs to a subfamily of the P-ATPase family, which absorbs and transports Zn, Cu, Pb, and Cd in plants. Here, we describe a ZmHMA-encoding HMA family protein that positively regulates Cd and Zn tolerance. The real-time fluorescence quantification (RT-PCR) results revealed that ZmHMA3 had a high expression in B73, and the expression of ZmHMA3 was sensitive to Cd in yeast cells, which was related to Cd accumulation in yeast. Additionally, the Arabidopsis thaliana homologous mutants of AtHMA2 showed Cd sensitivity compared with WT. The overexpressing ZmHMA3 plants showed higher tolerance under Cd and Zn stresses than the wild type. The overexpression of ZmHMA3 led to higher Cd and Zn accumulation in tissues based on the subcellular distribution analysis. We propose that ZmHMA3 improves maize tolerance to Cd and Zn stresses by absorbing and transporting Cd and Zn ions. This study elucidates the gene function of the ZmHMA3 response to Cd and Zn stress and provides a reference for improving the characteristics of heavy metals enrichment in existing maize varieties and the plant remediation technology of heavy-metal-contaminated soil. Full article

Plasmalogens are a unique family of cellular glycerophospholipids that contain a vinyl-ether bond. The synthesis of plasmalogens is initiated in peroxisomes and completed in the endoplasmic reticulum. Plasmalogens are transported to the post-Golgi compartment, including endosomes and plasma membranes, in a manner dependent on ATP, but not vesicular transport. Plasmalogens are preferentially localized in the inner leaflet of the plasma membrane in a manner dependent on P4-type ATPase ATP8B2, that associates with the CDC50 subunit. Plasmalogen biosynthesis is spatiotemporally regulated by a feedback mechanism that senses the amount of plasmalogens in the inner leaflet of the plasma membrane and controls the stability of fatty acyl-CoA reductase 1 (FAR1), the rate-limiting enzyme for plasmalogen biosynthesis. The physiological consequences of such asymmetric localization and homeostasis of plasmalogens are discussed in this review. Full article

Macleaya cordata is a dominant plant of mine tailings and a zinc (Zn) accumulator with high Zn tolerance. In this study, M. cordata seedlings cultured in Hoagland solution were treated with 200 μmol·L⁻¹ of Zn for 1 day or 7 days, and then, their leaves were taken for a comparative analysis of the transcriptomes and proteomes between the leaves of the control and Zn treatments. Differentially expressed genes included those that were iron (Fe)-deficiency-induced, such as vacuolar iron transporter VIT, ABC transporter ABCI17 and ferric reduction oxidase FRO. Those genes were significantly upregulated by Zn and could be responsible for Zn transport in the leaves of M. cordata. Differentially expressed proteins, such as chlorophyll a/b-binding proteins, ATP-dependent protease, and vacuolar-type ATPase located on the tonoplast, were significantly upregulated by Zn and, thus, could be important in chlorophyll biosynthesis and cytoplasm pH stabilization. Moreover, the changes in Zn accumulation, the production of hydrogen peroxide, and the numbers of mesophyll cells in the leaves of M. cordata were consistent with the expression of the genes and proteins. Thus, the proteins involved in the homeostasis of Zn and Fe are hypothesized to be the keys to the tolerance and accumulation of Zn in M. cordata. Such mechanisms in M. cordata can suggest novel approaches to genetically engineering and biofortifying crops. Full article

Polyamine homeostasis is disturbed in several human diseases, including cancer, which is hallmarked by increased intracellular polyamine levels and an upregulated polyamine transport system (PTS). Thus far, the polyamine transporters contributing to the elevated levels of polyamines in cancer cells have not yet been described, despite the fact that polyamine transport inhibitors are considered for cancer therapy. Here, we tested whether the upregulation of candidate polyamine transporters of the P5B transport ATPase family is responsible for the increased PTS in the well-studied breast cancer cell line MCF7 compared to the non-tumorigenic epithelial breast cell line MCF10A. We found that MCF7 cells presented elevated expression of a previously uncharacterized P5B-ATPase, ATP13A4, which was responsible for the elevated polyamine uptake activity. Furthermore, MCF7 cells were more sensitive to polyamine cytotoxicity, as demonstrated by cell viability, cell death and clonogenic assays. Importantly, the overexpression of ATP13A4 WT in MCF10A cells induced a MCF7 polyamine phenotype, with significantly higher uptake of BODIPY-labeled polyamines and increased sensitivity to polyamine toxicity. In conclusion, we established ATP13A4 as a new polyamine transporter in the human PTS and showed that ATP13A4 may play a major role in the increased polyamine uptake of breast cancer cells. ATP13A4 therefore emerges as a candidate therapeutic target for anticancer drugs that block the PTS. Full article

Cancer cachexia describes a syndrome of muscle wasting and lipolysis that is still largely untreatable and negatively impacts prognosis, mobility, and healthcare costs. Since upregulation of skeletal muscle monoamine-oxidase-A (MAO-A), a source of reactive oxygen species, may contribute to cachexia, we investigated the effects of the MAO-inhibitor harmine-hydrochloride (HH, intraperitoneal, 8 weeks) on muscle wasting in a triple-transgenic mouse model of pancreatic ductal adenocarcinoma (PDAC) and wild type (WT) mice. Gastrocnemius and soleus muscle cryo-cross-sections were analyzed for fiber type-specific cross-sectional area (CSA), fraction and capillarization using ATPase- and lectin-stainings. Transcripts of pro-apoptotic, -atrophic, and -inflammatory signals were determined by RT-qPCR. Furthermore, we evaluated the integrity of neuromuscular junction (NMJ, pre-/post-synaptic co-staining) and mitochondrial ultrastructure (transmission electron microscopy). MAO-A expression in gastrocnemius muscle was increased with PDAC vs. WT (immunohistochemistry: p < 0.05; Western blot: by trend). PDAC expectedly reduced fiber CSA and upregulated IL-1β in both calf muscles, while MuRF1 expression increased in soleus muscle only. Although IL-1β decreased, HH caused an additional 38.65% (p < 0.001) decrease in gastrocnemius muscle (IIBX) fiber CSA. Moreover, soleus muscle CSA remained unchanged despite the downregulation of E3-ligases FBXO32 (p < 0.05) and MuRF1 (p < 0.01) through HH. Notably, HH significantly decreased the post-synaptic NMJ area (quadriceps muscle) and glutathione levels (gastrocnemius muscle), thereby increasing mitochondrial damage and centronucleation in soleus and gastrocnemius type IIBX fibers. Moreover, although pro-atrophic/-inflammatory signals are reversed, HH unfortunately fails to stop and rather promotes PDAC-related muscle wasting, possibly via denervation or mitochondrial damage. These differential adverse vs. therapeutic effects warrant studies regarding dose-dependent benefits and risks with consideration of other targets of HH, such as the dual-specificity tyrosine phosphorylation regulated kinases 1A and B (DYRK1A/B). Full article