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BMC Musculoskeletal Disorders Dec 2023Current research on autophagy is mainly focused on intervertebral disc tissues and cells, while there is few on human peripheral blood sample. therefore, this study...
BACKGROUND
Current research on autophagy is mainly focused on intervertebral disc tissues and cells, while there is few on human peripheral blood sample. therefore, this study constructed a diagnostic model to identify autophagy-related markers of intervertebral disc degeneration (IVDD).
METHODS
GSE150408 and GSE124272 datasets were acquired from the Gene Expression Omnibus database, and differential expression analysis was performed. The IVDD-autophagy genes were obtained using Weighted Gene Coexpression Network Analysis, and a diagnostic model was constructed and validated, followed by Gene Set Variation Analysis (GSVA) and Gene Set Enrichment Analysis (GSEA). Meanwhile, miRNA-gene and transcription factor-gene interaction networks were constructed. In addition, drug-gene interactions and target genes of methylprednisolone and glucosamine were analyzed.
RESULTS
A total of 1,776 differentially expressed genes were identified between IVDD and control samples, and the composition of the four immune cell types was significantly different between the IVDD and control samples. The Meturquoise and Mebrown modules were significantly related to immune cells, with significant differences between the control and IVDD samples. A diagnostic model was constructed using five key IVDD-autophagy genes. The area under the curve values of the model in the training and validation datasets were 0.907 and 0.984, respectively. The enrichment scores of the two pathways were significantly different between the IVDD and healthy groups. Eight pathways in the IVDD and healthy groups had significant differences. A total of 16 miRNAs and 3 transcription factors were predicted to be of great value. In total, 84 significantly related drugs were screened for five key IVDD-autophagy genes in the diagnostic model, and three common autophagy-related target genes of methylprednisolone and glucosamine were predicted.
CONCLUSION
This study constructs a reliable autophagy-related diagnostic model that is strongly related to the immune microenvironment of IVD. Autophagy-related genes, including PHF23, RAB24, STAT3, TOMM5, and DNAJB9, may participate in IVDD pathogenesis. In addition, methylprednisolone and glucosamine may exert therapeutic effects on IVDD by targeting CTSD, VEGFA, and BAX genes through apoptosis, as well as the sphingolipid and AGE-RAGE signaling pathways in diabetic complications.
Topics: Humans; Intervertebral Disc Degeneration; Intervertebral Disc; Transcription Factors; Autophagy; Methylprednisolone; Glucosamine; Membrane Proteins; Molecular Chaperones; HSP40 Heat-Shock Proteins; Homeodomain Proteins
PubMed: 38041088
DOI: 10.1186/s12891-023-06886-w -
The Protein Journal Feb 2024Therapeutic proteins are potent, fast-acting drugs that are highly effective in treating various conditions. Medicinal protein usage has increased in the past 10 years,... (Review)
Review
Therapeutic proteins are potent, fast-acting drugs that are highly effective in treating various conditions. Medicinal protein usage has increased in the past 10 years, and it will evolve further as we better understand disease molecular pathways. However, it is associated with high processing costs, limited stability, difficulty in being administered as an oral medication, and the inability of large proteins to penetrate tissue and reach their target locations. Many methods have been developed to overcome the problems with the stability and chaperone activity of therapeutic proteins, viz., the addition of external agents (changing the properties of the surrounding solvent by using stabilizing excipients, e.g., amino acids, sugars, polyols) and internal agents (chemical modifications that influence its structural properties, e.g., mutations, glycosylation). However, these methods must completely clear protein instability and chaperone issues. There is still much work to be done on finetuning chaperone proteins to increase their biological efficacy and stability. Methylglyoxal (MGO), a potent dicarbonyl compound, reacts with proteins and forms covalent cross-links. Much research on MGO scavengers has been conducted since they are known to alter protein structure, which may result in alterations in biological activity and stability. MGO is naturally produced within our body, however, its impact on chaperones and protein stability needs to be better understood and seems to vary based on concentration. This review highlights the efforts of several research groups on the effect of MGO on various proteins. It also addresses the impact of MGO on a client protein, α-crystallin, to understand the potential solutions to the protein's chaperone and stability problems.
Topics: Humans; Pyruvaldehyde; Magnesium Oxide; alpha-Crystallins; Molecular Chaperones; Protein Folding
PubMed: 38017314
DOI: 10.1007/s10930-023-10166-w -
International Journal of Molecular... Mar 2024A neurological condition called dystonia results in abnormal, uncontrollable postures or movements because of sporadic or continuous muscular spasms. Several varieties... (Review)
Review
A neurological condition called dystonia results in abnormal, uncontrollable postures or movements because of sporadic or continuous muscular spasms. Several varieties of dystonia can impact people of all ages, leading to severe impairment and a decreased standard of living. The discovery of genes causing variations of single or mixed dystonia has improved our understanding of the disease's etiology. Genetic dystonias are linked to several genes, including pathogenic variations of VPS16, TOR1A, THAP1, GNAL, and ANO3. Diagnosis of dystonia is primarily based on clinical symptoms, which can be challenging due to overlapping symptoms with other neurological conditions, such as Parkinson's disease. This review aims to summarize recent advances in the genetic origins and management of focal dystonia.
Topics: Humans; Dystonia; Dystonic Disorders; Movement; Parkinson Disease; Molecular Chaperones; DNA-Binding Proteins; Apoptosis Regulatory Proteins; Anoctamins
PubMed: 38612382
DOI: 10.3390/ijms25073571 -
Food and Chemical Toxicology : An... Nov 2023Parkinson's disease (PD) is characterized by motor impairments and progressive dopaminergic neuronal death in the substantia nigra (SN). Recently, the involvement of...
Parkinson's disease (PD) is characterized by motor impairments and progressive dopaminergic neuronal death in the substantia nigra (SN). Recently, the involvement of other regulated cell death (RCD) machineries has been highlighted in PD. Necroptosis is controlled by p-RIPK1, p-RIPK3, and p-MLKL and negatively regulated by caspase-8. Ferroptosis is characterized by iron overload and accumulation of reactive oxygen species. Interestingly, the molecular chaperone complex HSP90/CDC37 has been reported to directly regulate necroptosis, ferroptosis, and some PD-associated proteins. We investigated the potential anti-necroptotic and anti-ferroptotic effects of the anti-cancer drug pazopanib, uncovering the HSP90/CDC37 complex as a master RCD modulator in rotenone-induced Parkinsonism in rats. Oral administration of 15 mg/kg pazopanib to rotenone-intoxicated rats for three weeks improved motor deficits, debilitated histopathological changes, and increased striatal dopaminergic levels. Pazopanib suppressed LRRK2 and c-Abl. Pazopanib displayed an anti-necroptotic effect through inhibition of the p-RIPK1/p-RIPK3/p-MLKL pathway and activation of caspase-8. Moreover, pazopanib inhibited the ferroptotic p-VEGFR2-PKCβII-PLC-γ-ACSL-4 pathway, iron, 4-HNE, and PTGS2 while increasing GPX-4 and GSH levels. Taken together, the current research sheds light on the repositioning of pazopanib targeting HSP90/CDC37 and its multiple RCD mechanisms, which would offer a new perspective for therapeutic strategies in PD.
Topics: Rats; Animals; Rotenone; Caspase 8; Parkinsonian Disorders; Parkinson Disease; Dopamine; Ferroptosis; Molecular Chaperones; HSP90 Heat-Shock Proteins
PubMed: 37820786
DOI: 10.1016/j.fct.2023.114069 -
Current Opinion in Microbiology Oct 2023Hsp90 is a conserved molecular chaperone that facilitates the folding and function of hundreds of client proteins, many of which serve as core hubs of signal... (Review)
Review
Hsp90 is a conserved molecular chaperone that facilitates the folding and function of hundreds of client proteins, many of which serve as core hubs of signal transduction networks. Hsp90 has a critical role in virulence of the opportunistic fungal pathogen Candida albicans, which exists as a natural commensal of the human microbiota and is a leading cause of invasive fungal infections, particularly in immunocompromised individuals. The ability of C. albicans to cause disease is tightly coupled to its capacity to undergo a morphogenetic transition between yeast and filamentous forms. Here, we describe the complex mechanisms by which Hsp90 regulates C. albicans morphogenesis and virulence, and explore the potential of targeting fungal Hsp90 as a therapeutic strategy to combat fungal infections.
Topics: Humans; Candida albicans; Fungal Proteins; Virulence; HSP90 Heat-Shock Proteins; Morphogenesis
PubMed: 37399670
DOI: 10.1016/j.mib.2023.102351 -
Structure (London, England : 1993) Jun 2024Group I chaperonins are dual heptamer protein complexes that play significant roles in protein homeostasis. The structure and function of the Escherichia coli chaperonin...
Group I chaperonins are dual heptamer protein complexes that play significant roles in protein homeostasis. The structure and function of the Escherichia coli chaperonin are well characterized. However, the dynamic properties of chaperonins, such as large ATPase-dependent conformational changes by binding of lid-like co-chaperonin GroES, have made structural analyses challenging, and our understanding of these changes during the turnover of chaperonin complex formation is limited. In this study, we used single-particle cryogenic electron microscopy to investigate the structures of GroES-bound chaperonin complexes from the thermophilic hydrogen-oxidizing bacteria Hydrogenophilus thermoluteolus and Hydrogenobacter thermophilus in the presence of ATP and AMP-PNP. We captured the structure of an intermediate state chaperonin complex, designated as an asymmetric football-shaped complex, and performed analyses to decipher the dynamic structural variations. Our structural analyses of inter- and intra-subunit communications revealed a unique mechanism of complex formation through the binding of a second GroES to a bullet-shaped complex.
Topics: Cryoelectron Microscopy; Models, Molecular; Adenosine Triphosphate; Protein Binding; Chaperonin 10; Bacterial Proteins; Adenylyl Imidodiphosphate; Protein Conformation; Hydrogenophilaceae; Protein Subunits
PubMed: 38492570
DOI: 10.1016/j.str.2024.02.012 -
Metabolism: Clinical and Experimental Sep 2023Central to the pathogenesis of nonalcoholic fatty liver disease (NAFLD) is the accumulation of lipids in the liver and various fat tissues. We aimed to elucidate the...
BACKGROUND AND AIMS
Central to the pathogenesis of nonalcoholic fatty liver disease (NAFLD) is the accumulation of lipids in the liver and various fat tissues. We aimed to elucidate the mechanisms by which lipid droplets (LDs) in the liver and adipocytes are degraded by the autophagy-lysosome system and develop therapeutic means to modulate lipophagy, i.e., autophagic degradation of LDs.
METHODS
We monitored the process in which LDs are pinched off by autophagic membranes and degraded by lysosomal hydrolases in cultured cells and mice. The autophagic receptor p62/SQSTM-1/Sequestosome-1 was identified as a key regulator and used as a target to develop drugs to induce lipophagy. The efficacy of p62 agonists was validated in mice to treat hepatosteatosis and obesity.
RESULTS
We found that the N-degron pathway modulates lipophagy. This autophagic degradation initiates when the molecular chaperones including BiP/GRP78, retro-translocated from the endoplasmic reticulum, is N-terminally (Nt-) arginylated by ATE1 R-transferase. The resulting Nt-arginine (Nt-Arg) binds the ZZ domain of p62 associated with LDs. Upon binding to Nt-Arg, p62 undergoes self-polymerization and recruits LC3 phagophores to the site of lipophagy, leading to lysosomal degradation. Liver-specific Ate1 conditional knockout mice under high fat diet developed severe NAFLD. The Nt-Arg was modified into small molecule agonists to p62 that facilitate lipophagy in mice and exerted therapeutic efficacy in obesity and hepatosteatosis of wild-type but not p62 knockout mice.
CONCLUSIONS
Our results show that the N-degron pathway modulates lipophagy and provide p62 as a drug target to treat NAFLD and other diseases related with metabolic syndrome.
Topics: Animals; Mice; Non-alcoholic Fatty Liver Disease; Proteolysis; Autophagy; Endoplasmic Reticulum Chaperone BiP; Obesity; Mice, Knockout
PubMed: 37385404
DOI: 10.1016/j.metabol.2023.155644 -
Molecular Cell Sep 2023General protein folding is mediated by chaperones that utilize ATP hydrolysis to regulate client binding and release. Zinc-finger protein 1 (Zpr1) is an essential...
General protein folding is mediated by chaperones that utilize ATP hydrolysis to regulate client binding and release. Zinc-finger protein 1 (Zpr1) is an essential ATP-independent chaperone dedicated to the biogenesis of eukaryotic translation elongation factor 1A (eEF1A), a highly abundant GTP-binding protein. How Zpr1-mediated folding is regulated to ensure rapid Zpr1 recycling remains an unanswered question. Here, we use yeast genetics and microscopy analysis, biochemical reconstitution, and structural modeling to reveal that folding of eEF1A by Zpr1 requires GTP hydrolysis. Furthermore, we identify the highly conserved altered inheritance of mitochondria 29 (Aim29) protein as a Zpr1 co-chaperone that recognizes eEF1A in the GTP-bound, pre-hydrolysis conformation. This interaction dampens Zpr1⋅eEF1A GTPase activity and facilitates client exit from the folding cycle. Our work reveals that a bespoke ATP-independent chaperone system has mechanistic similarity to ATPase chaperones but unexpectedly relies on client GTP hydrolysis to regulate the chaperone-client interaction.
Topics: Humans; Adenosine Triphosphate; GTP Phosphohydrolases; Guanosine Triphosphate; Molecular Chaperones; Peptide Elongation Factors; Saccharomyces cerevisiae; Carrier Proteins; Saccharomyces cerevisiae Proteins; Protein Folding
PubMed: 37597513
DOI: 10.1016/j.molcel.2023.07.028 -
EMBO Reports Apr 2024Teratozoospermia is a significant cause of male infertility, but the pathogenic mechanism of acephalic spermatozoa syndrome (ASS), one of the most severe...
Teratozoospermia is a significant cause of male infertility, but the pathogenic mechanism of acephalic spermatozoa syndrome (ASS), one of the most severe teratozoospermia, remains elusive. We previously reported Spermatogenesis Associated 6 (SPATA6) as the component of the sperm head-tail coupling apparatus (HTCA) required for normal assembly of the sperm head-tail conjunction, but the underlying molecular mechanism has not been explored. Here, we find that the co-chaperone protein BAG5, expressed in step 9-16 spermatids, is essential for sperm HTCA assembly. BAG5-deficient male mice show abnormal assembly of HTCA, leading to ASS and male infertility, phenocopying SPATA6-deficient mice. In vivo and in vitro experiments demonstrate that SPATA6, cargo transport-related myosin proteins (MYO5A and MYL6) and dynein proteins (DYNLT1, DCTN1, and DNAL1) are misfolded upon BAG5 depletion. Mechanistically, we find that BAG5 forms a complex with HSPA8 and promotes the folding of SPATA6 by enhancing HSPA8's affinity for substrate proteins. Collectively, our findings reveal a novel protein-regulated network in sperm formation in which BAG5 governs the assembly of the HTCA by activating the protein-folding function of HSPA8.
Topics: Animals; Humans; Male; Mice; Adaptor Proteins, Signal Transducing; Cytoskeletal Proteins; Dyneins; HSC70 Heat-Shock Proteins; Infertility, Male; Molecular Chaperones; Protein Folding; Semen; Sperm Head; Spermatogenesis; Spermatozoa; Teratozoospermia; Thiazoles
PubMed: 38454159
DOI: 10.1038/s44319-024-00112-x -
Experimental & Molecular Medicine Feb 2024H3.3, the most common replacement variant for histone H3, has emerged as an important player in chromatin dynamics for controlling gene expression and genome integrity.... (Review)
Review
H3.3, the most common replacement variant for histone H3, has emerged as an important player in chromatin dynamics for controlling gene expression and genome integrity. While replicative variants H3.1 and H3.2 are primarily incorporated into nucleosomes during DNA synthesis, H3.3 is under the control of H3.3-specific histone chaperones for spatiotemporal incorporation throughout the cell cycle. Over the years, there has been progress in understanding the mechanisms by which H3.3 affects domain structure and function. Furthermore, H3.3 distribution and relative abundance profoundly impact cellular identity and plasticity during normal development and pathogenesis. Recurrent mutations in H3.3 and its chaperones have been identified in neoplastic transformation and developmental disorders, providing new insights into chromatin biology and disease. Here, we review recent findings emphasizing how two distinct histone chaperones, HIRA and DAXX, take part in the spatial and temporal distribution of H3.3 in different chromatin domains and ultimately achieve dynamic control of chromatin organization and function. Elucidating the H3.3 deposition pathways from the available histone pool will open new avenues for understanding the mechanisms by which H3.3 epigenetically regulates gene expression and its impact on cellular integrity and pathogenesis.
Topics: Cell Cycle; Cell Division; Chromatin; Histone Chaperones; Histones; Humans; Molecular Chaperones; Co-Repressor Proteins; Transcription Factors; Cell Cycle Proteins
PubMed: 38297159
DOI: 10.1038/s12276-023-01145-3