ABSTRACT
Membrane dynamics are important to the integrity and function of mitochondria. Defective mitochondrial fusion underlies the pathogenesis of multiple diseases. The ability to target fusion highlights the potential to fight life-threatening conditions. Here we report a small molecule agonist, S89, that specifically promotes mitochondrial fusion by targeting endogenous MFN1. S89 interacts directly with a loop region in the helix bundle 2 domain of MFN1 to stimulate GTP hydrolysis and vesicle fusion. GTP loading or competition by S89 dislodges the loop from the GTPase domain and unlocks the molecule. S89 restores mitochondrial and cellular defects caused by mitochondrial DNA mutations, oxidative stress inducer paraquat, ferroptosis inducer RSL3 or CMT2A-causing mutations by boosting endogenous MFN1. Strikingly, S89 effectively eliminates ischemia/reperfusion (I/R)-induced mitochondrial damage and protects mouse heart from I/R injury. These results reveal the priming mechanism for MFNs and provide a therapeutic strategy for mitochondrial diseases when additional mitochondrial fusion is beneficial.
Subject(s)
Mitochondrial Dynamics , Mitochondrial Membrane Transport Proteins , Mice , Animals , Mitochondrial Membrane Transport Proteins/analysis , Mitochondrial Membrane Transport Proteins/chemistry , Mitochondrial Membrane Transport Proteins/genetics , Mitochondria , Hydrolysis , Guanosine Triphosphate/analysis , Guanosine Triphosphate/pharmacology , Mitochondrial Proteins/genetics , Mitochondrial Proteins/analysis , Mitochondrial Proteins/pharmacologyABSTRACT
The mitochondrion is a key intracellular organelle regulating metabolic processes, oxidative stress, energy production, calcium homeostasis, and cell survival. Protein phosphorylation plays an important role in regulating mitochondrial functions and cellular signaling pathways. Dysregulation of protein phosphorylation status can cause protein malfunction and abnormal signal transduction, leading to organ dysfunction and disease. Investigating the mitochondrial phosphoproteins is therefore crucial to better understand the molecular and pathogenic mechanisms of many metabolic disorders. Conventional analyses of phosphoproteins, for instance, via western blotting, can be done only for proteins for which specific antibodies to their phosphorylated forms are available. Moreover, such an approach is not suitable for large-scale study of phosphoproteins. Currently, proteomics represents an important tool for large-scale analysis of proteins and their post-translational modifications, including phosphorylation. Here, we provide step-by-step protocols for the proteomics analysis of mitochondrial phosphoproteins (the phosphoproteome), using renal tubular cells as an example. These protocols include methods to effectively isolate mitochondria and to validate the efficacy of mitochondrial enrichment as well as its purity. We also provide detailed protocols for performing both gel-based and gel-free phosphoproteome analyses. The gel-based analysis involves two-dimensional gel electrophoresis and phosphoprotein-specific staining, followed by protein identification via mass spectrometry, whereas the gel-free approach is based on in-solution mass spectrometric identification of specific phosphorylation sites and residues. In all, these approaches allow large-scale analyses of mitochondrial phosphoproteins that can be applied to other cells and tissues of interest. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Mitochondrial isolation/purification from renal tubular cells Support Protocol: Validation of enrichment efficacy and purity of mitochondrial isolation Basic Protocol 2: Gel-based phosphoproteome analysis Basic Protocol 3: Gel-free phosphoproteome analysis.
Subject(s)
Mitochondria , Mitochondrial Proteins , Phosphoproteins , Proteomics , Electrophoresis, Gel, Two-Dimensional , Mitochondria/chemistry , Mitochondrial Proteins/analysis , Phosphoproteins/analysis , Proteome/analysis , Proteomics/methodsABSTRACT
BACKGROUND: Gastric cancer (GC) is the world's second-leading cause of cancer-related mortality, continuing to make it a serious healthcare concern. Even though the prevalence of GC reduces, the prognosis for GC patients remains poor in terms of a lack of reliable biomarkers to diagnose early GC and predict chemosensitivity and recurrence. METHODS AND MATERIAL: We integrated the gene expression patterns of gastric cancers from four RNAseq datasets (GSE113255, GSE142000, GSE118897, and GSE130823) from Gene Expression Omnibus (GEO) database to recognize differentially expressed genes (DEGs) between normal and GC samples. A gene co-expression network was built using weighted co-expression network analysis (WGCNA). Furthermore, RT-qPCR was performed to validate the in silico results. RESULTS: The red modules in GSE113255, Turquoise in GSE142000, Brown in GSE118897, and the green-yellow module in GSE130823 datasets were found to be highly correlated with the anatomical site of GC. ITGAX, CCL14, ADHFE1, and HOXB13) as the hub gene are differentially expressed in tumor and non-tumor gastric tissues in this study. RT-qPCR demonstrated a high level of the expression of this gene. CONCLUSION: The expression levels of ITGAX, CCL14, ADHFE1, and HOXB13 in GC tumor tissues are considerably greater than in adjacent normal tissues. Systems biology approaches identified that these genes could be possible GC marker genes, providing ideas for other experimental studies in the future.
Subject(s)
Biomarkers, Tumor , Gene Expression Regulation, Neoplastic/genetics , Stomach Neoplasms , Alcohol Oxidoreductases/analysis , Biomarkers, Tumor/analysis , Biomarkers, Tumor/metabolism , Chemokines, CC/analysis , Computational Biology/methods , Early Detection of Cancer/methods , Gene Expression Profiling/methods , Gene Regulatory Networks , Homeodomain Proteins/analysis , Humans , Mitochondrial Proteins/analysis , Prognosis , Stomach Neoplasms/diagnosis , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathologyABSTRACT
BACKGROUND: Chloride intracellular channel 4 (CLIC4) is a multifunctional metamorphic protein for which a growing body of evidence supports a major role in the brain's molecular and behavioral responses to ethanol (EtOH). Although key to understanding the functional biology underlying this role, little is known about the cellular and subcellular expression patterns of CLIC4 in brain and how they are affected by EtOH. METHODS: We used qRT-PCR to assess Clic4 mRNA expression in the medial prefrontal cortex (mPFC) of C57BL/6J mice in the absence and presence of acute EtOH exposure. Two complementary immunohistochemical techniques were employed to assess the subcellular localization of the CLIC4 protein and its pattern of expression across brain cell types in the mPFC in the absence and presence of acute EtOH. RESULTS: Through immunohistochemical and stereological techniques, we show that CLIC4 protein is robustly expressed by oligodendrocytes (most abundant), microglia, and astrocytes, with minimal expression in neurons. Following acute EtOH exposure, we observed a rapid increase in Clic4 mRNA expression in female but not male mice and an overall increase in the number of oligodendrocytes and astrocytes expressing the CLIC4 protein. CONCLUSIONS: These findings suggest that Clic4 functions as an early response gene for acute EtOH in brain, which likely underlies its ability to modulate EtOH behavior. Our results also suggest that the role of CLIC4 in the brain's response to EtOH is mediated through oligodendrocytes.
Subject(s)
Chloride Channels/genetics , Ethanol/pharmacology , Gene Expression Regulation/drug effects , Mitochondrial Proteins/genetics , Prefrontal Cortex/metabolism , Transcriptome/drug effects , Animals , Astrocytes/metabolism , Astrocytes/ultrastructure , Behavior, Animal/drug effects , Chloride Channels/analysis , Chloride Channels/physiology , Female , Male , Mice , Mice, Inbred C57BL , Mitochondrial Proteins/analysis , Mitochondrial Proteins/physiology , Oligodendroglia/metabolism , Prefrontal Cortex/chemistry , Prefrontal Cortex/drug effects , RNA, Messenger/analysis , Sex CharacteristicsABSTRACT
In this work, a simple and ultrasensitive colorimetric biosensor for detection of SURF1 gene fragments (Leigh syndrome) has been developed based on a dual DNA-induced cascade hybridization reaction. Firstly, a biotin labeled capture probe was immobilized on a streptavidin labeled 96-well transparent plate surface. Then the target SURF1 fragment and auxiliary probe S1 were added into the reaction system to form a "Y" structure with the capture probe. Furthermore, to achieve a highly efficient signal amplification strategy, digoxin labeled P1, P2, P3 and P4 probes were used to cause a dual DNA-induced cascade hybridization reaction on the "Y" structure of the 96-well plate surface. As a detection probe, the HRP anti-digoxin antibody was combined on the surface to produce a colorimetric response to the SURF1 fragment in the presence of TMB. Under the optimal conditions, the established method exhibited a wide linear range from 1.0 × 10-13 M to 1.0 × 10-8 M and a detection limit to SURF1 as low as 1.73 × 10-14 M. In addition, the strategy has been successfully applied to the detection of SURF1 in spiked human serum samples. Therefore, the established biosensor has potential application prospects in gene fragment analysis and early diagnosis of clinical diseases.
Subject(s)
Biosensing Techniques , Colorimetry , Membrane Proteins/analysis , Mitochondrial Proteins/analysis , DNA/genetics , Humans , Nucleic Acid Hybridization , StreptavidinABSTRACT
Background: Bioinformatic analysis has revealed that OXR1 is significantly downregulated in muscle-invasive bladder cancer. Patients & methods: The expression of OXR1 in patients with urothelial carcinoma was evaluated by immunohistochemistry, including 340 cases with urothelial carcinoma in the upper urinary tract and 295 in the urinary bladder. Results: Low expression of OXR1 was significantly correlated with adverse pathological parameters including high primary tumor (pT) stage, high node stage, high histological grade, high mitotic activity and increased vascular or perineural invasion (all p < 0.05). Low expression of OXR1 independently predicted worse metastasis-free survival (p = 0.033) in urothelial carcinoma of the upper urinary tract and worse disease-specific survival (p = 0.022) and metastasis-free survival (p < 0.001) in urothelial carcinoma of the urinary bladder. Conclusion: Low expression of OXR1 is an adverse prognostic factor in urothelial carcinoma.
Subject(s)
Carcinoma, Transitional Cell/mortality , Mitochondrial Proteins/analysis , Urologic Neoplasms/mortality , Adult , Aged , Carcinoma, Transitional Cell/chemistry , Carcinoma, Transitional Cell/pathology , Female , Humans , Immunohistochemistry , Male , Middle Aged , Neoplasm Staging , Prognosis , Urologic Neoplasms/chemistry , Urologic Neoplasms/pathologyABSTRACT
This study aimed to identify species of Fasciola flukes in Dali Prefecture (Yunnan Province, China) and analyze their genetic diversity. Fasciola flukes (n = 122) were collected from cattle livers in a farmers' market in Xiaguan Town, Dali Prefecture. Nucleotide sequences of ribosomal internal transcribed spacer (ITS) as well as nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) and mitochondrial cytochrome c oxidase subunit 1 (CO1) were amplified, sequenced, and subjected to homology analysis. The heterozygosity ratios of different ITS alleles were determined using the peak-height ratio of heterozygous loci. Multiplex PCR analysis of the nuclear protein coding gene, phosphoenolpyruvate carboxykinase (pepck), was used to identify Fasciola species. Multiple ND1 sequence alignments enabled further genetic diversity analysis of regional Fasciola flukes. Seven ITS sequences belonged to F. hepatica and 115 belonged to Fh/Fg heterozygous flukes. Sequencing analysis of heterozygous flukes revealed 11 heterozygous loci with double peaks, with significantly variable ratios among individuals. ND1 and CO1 results indicated that one specimen was identical to F. hepatica, while 121 specimens were identical to F. gigantica or contained one variable site. Multiplex PCR results for pepck showed that double bands for F. hepatica and F. gigantica were amplified from Dali Fasciola specimens; hence, they were all heterozygous. By combining ITS, ND1, and CO1 sequences with multiplex pepck PCR results, all 122 specimens were identified as Fh/Fg heterozygous Fasciola flukes. Our experimental results preliminarily confirmed a high degree of Fh/Fg heterozygosity among Fasciola flukes in the Dali area. Selecting multiple molecular markers for concurrent analysis will provide more comprehensive and accurate genetic information.
Subject(s)
Cattle Diseases/parasitology , Fasciola/genetics , Fascioliasis/veterinary , Polymorphism, Genetic , Animals , Base Sequence , Cattle , China , Fasciola/classification , Fasciola/isolation & purification , Fascioliasis/parasitology , Helminth Proteins/analysis , Liver Diseases/parasitology , Liver Diseases/veterinary , Mitochondrial Proteins/analysis , NADH Dehydrogenase/analysis , Sequence Alignment/veterinaryABSTRACT
Mitochondrial proteins, most of which are encoded in the nucleus and the rest of which are regulated by the mitochondrial genome, play pivotal roles in essential cellular functions. However, fluorescent probes that can be used for monitoring mitochondrial proteins have not yet been widely developed, thereby severely limiting the exploration of the functions of proteins in mitochondria. Towards this end, here we propose a near-infrared (NIR) fluorescence probe MPP to effectively illuminate the dynamic changes in mitochondrial proteins in live cells under oxidative stress, with excellent temporal and spatial resolution. Of particular importance, MPP extends the study of the pharmacology involved in apoptosis induced by anti-cancer drugs (hydroxycamptothecin (HCPT), epirubicin (Epi) and cyclophosphamide (CPA)) for the first time. Furthermore, employing a protein-activatable strategy, this probe could serve as an excellent phototherapeutic agent in photodynamic therapy (PDT). Finally, in vivo experiments suggest that this versatile probe can be used to image tumors in HeLa tumor-bearing mice for 24 h, which demonstrates that our probe could play a dual role as a robust phototherapeutic and imaging agent.
Subject(s)
Aniline Compounds/pharmacology , Antineoplastic Agents/pharmacology , Fluorescent Dyes/pharmacology , Mitochondrial Proteins/analysis , Optical Imaging , Photochemotherapy , Photosensitizing Agents/pharmacology , Aniline Compounds/chemical synthesis , Aniline Compounds/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Camptothecin/analogs & derivatives , Camptothecin/chemistry , Camptothecin/pharmacology , Cell Line , Cell Survival/drug effects , Cyclophosphamide/chemistry , Cyclophosphamide/pharmacology , Drug Screening Assays, Antitumor , Epirubicin/chemistry , Epirubicin/pharmacology , Fluorescent Dyes/chemical synthesis , Fluorescent Dyes/chemistry , Humans , Infrared Rays , Molecular Structure , Photosensitizing Agents/chemical synthesis , Photosensitizing Agents/chemistryABSTRACT
The present study describes three new species of monogenean parasites of characid fishes from the Upper Paraná River basin, Brazil: Characithecium paranapanemense n. sp. on Psalidodon paranae and Psalidodon bockmanni, Diaphorocleidus magnus n. sp. on Astyanax lacustris and Psalidodon fasciatus, and Diaphorocleidus neotropicalis n. sp. on Astyanax lacustris and P. bockmanni. An amendment for Diaphorocleidus is proposed, since additional characters observed in the new species required to extend the generic diagnostic features mainly to include: articulation process connecting the base of the MCO with accessory piece present or absent, and accessory piece with variable shapes (plate-like, pincer-shaped, wrench-shaped, sheath-shaped), divided or not into subunits. Characithecium paranapanemense n. sp. can be distinguished from other congeners by the morphology of its MCO and accessory piece. Diaphorocleidus magnus n. sp. differs from most of its congeners by the morphology of its accessory piece, the presence of articulation process connecting the base of the MCO with accessory piece, and the morphology of the sclerotized structures of the haptor. Diaphorocleidus neotropicalis n. sp. can be easily distinguished from its congeners by the morphology of the accessory piece, the sclerotized structures of the haptor and the morphology of the vagina. Molecular data of the new species (partial 28S rDNA and mitochondrial cytochrome oxidase I) were obtained and the first phylogenetic analysis based on 28S rDNA gene sequences for species of Characithecium and Diaphorocleidus are provided. Although Diaphorocleidus and Characithecium share some morphological similarities, phylogenetic analysis indicates that species of these two genera are not closely related.
Subject(s)
Characidae , Fish Diseases/parasitology , Trematoda/classification , Trematode Infections/veterinary , Animals , Brazil/epidemiology , DNA, Helminth/analysis , DNA, Ribosomal/analysis , Electron Transport Complex IV/analysis , Helminth Proteins/analysis , Male , Mitochondrial Proteins/analysis , Prevalence , Trematoda/anatomy & histology , Trematoda/cytology , Trematoda/genetics , Trematode Infections/parasitologyABSTRACT
In mitochondrial oxidative phosphorylation (Ox-Phos), individual electron transport chain complexes are thought to assemble into supramolecular entities termed supercomplexes (SCs). The technique of blue native (BN) gel electrophoresis has emerged as the method of choice for analyzing SCs. However, the process of sample extraction for BN gel analysis is somewhat tedious and introduces the possibility for experimental artifacts. Here we outline a streamlined method that eliminates a centrifugation step and provides a more representative sampling of a population of mitochondria on the final gel. Using this method, we show that SC composition does not appear to change dynamically with altered mitochondrial function.
Subject(s)
Electron Transport Chain Complex Proteins/analysis , Heart/physiology , Mitochondria, Heart/chemistry , Mitochondrial Proteins/analysis , Multiprotein Complexes/analysis , Myocardium/chemistry , Native Polyacrylamide Gel Electrophoresis/methods , Animals , Electron Transport Chain Complex Proteins/metabolism , Mice , Mitochondria, Heart/metabolism , Mitochondrial Proteins/metabolism , Multiprotein Complexes/metabolism , Myocardium/metabolism , Oxidative PhosphorylationABSTRACT
Nitrotyrosine formation is caused by presence of reactive oxygen and nitrogen species. Nitration is a very selective process leading to specific modification of only a few tyrosines in protein molecule. 2D electrophoresis and western blotting techniques coupled with mass spectrometry are common methods used in analysis of proteome. Here we describe protocol for analysis of peroxynitrite-induced protein nitration in isolated mitochondria. Mitochondrial proteins are separated by 2D electrophoresis and transferred to nitrocellulose membrane. Membranes are then incubated with antibodies against nitrotyrosine. Positive spots are compared with corresponding Coomassie-stained gels, and protein nitration is confirmed with mass spectrometry techniques.
Subject(s)
Electrophoresis, Gel, Two-Dimensional/methods , Immunoblotting/methods , Mass Spectrometry/methods , Mitochondria, Heart/chemistry , Mitochondrial Proteins/analysis , Peroxynitrous Acid/chemistry , Tyrosine/analogs & derivatives , Animals , Cattle , Mitochondria, Heart/metabolism , Mitochondrial Proteins/metabolism , Tyrosine/analysis , Tyrosine/metabolismABSTRACT
PURPOSE: To analyze the role of six human epididymis protein 4 (HE4)-related mitochondrial ribosomal proteins (MRPs) in ovarian cancer and selected MRPL15, which is most closely related to the tumorigenesis and prognosis of ovarian cancer, for further analyses. METHODS: Using STRING database and MCODE plugin in Cytoscape, six MRPs were identified among genes that are upregulated in response to HE4 overexpression in epithelial ovarian cancer cells. The Cancer Genome Atlas (TCGA) ovarian cancer, GTEX, Oncomine, and TISIDB were used to analyze the expression of the six MRPs. The prognostic impact and genetic variation of these six MRPs in ovarian cancer were evaluated using Kaplan-Meier Plotter and cBioPortal, respectively. MRPL15 was selected for immunohistochemistry and GEO verification. TCGA ovarian cancer data, gene set enrichment analysis, and Enrichr were used to explore the mechanism of MRPL15 in ovarian cancer. Finally, the relationship between MRPL15 expression and immune subtype, tumor-infiltrating lymphocytes, and immune regulatory factors was analyzed using TCGA ovarian cancer data and TISIDB. RESULTS: Six MRPs (MRPL10, MRPL15, MRPL36, MRPL39, MRPS16, and MRPS31) related to HE4 in ovarian cancer were selected. MRPL15 was highly expressed and amplified in ovarian cancer and was related to the poor prognosis of patients. Mechanism analysis indicated that MRPL15 plays a role in ovarian cancer through pathways such as the cell cycle, DNA repair, and mTOR 1 signaling. High expression of MRPL15 in ovarian cancer may be associated with its amplification and hypomethylation. Additionally, MRPL15 showed the lowest expression in C3 ovarian cancer and was correlated with proliferation of CD8+ T cells and dendritic cells as well as TGFßR1 and IDO1 expression. CONCLUSION: MRPL15 may be a prognostic indicator and therapeutic target for ovarian cancer. Because of its close correlation with HE4, this study provides insights into the mechanism of HE4 in ovarian cancer.
Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Ovarian Epithelial/metabolism , Mitochondrial Proteins/metabolism , Ovarian Neoplasms/metabolism , RNA-Binding Proteins/metabolism , Ribosomal Proteins/metabolism , WAP Four-Disulfide Core Domain Protein 2/metabolism , Adult , Aged , Biomarkers, Tumor/analysis , Biomarkers, Tumor/genetics , CD8-Positive T-Lymphocytes/cytology , Carcinoma, Ovarian Epithelial/chemistry , Carcinoma, Ovarian Epithelial/genetics , Carcinoma, Ovarian Epithelial/pathology , Cell Proliferation/genetics , Databases, Genetic , Female , Humans , Kaplan-Meier Estimate , Middle Aged , Mitochondrial Proteins/analysis , Mitochondrial Proteins/genetics , Ovarian Neoplasms/chemistry , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Ovary/chemistry , Ovary/metabolism , Prognosis , RNA, Messenger/analysis , RNA-Binding Proteins/analysis , RNA-Binding Proteins/genetics , Ribosomal Proteins/analysis , Ribosomal Proteins/genetics , Up-Regulation , WAP Four-Disulfide Core Domain Protein 2/analysis , WAP Four-Disulfide Core Domain Protein 2/genetics , Young AdultABSTRACT
An Isospora species, Isospora amphiboluri, originally described by Canon in 1967 and later by McAllister et al. (1995), was isolated from a central netted dragon (Ctenophorus nuchalis) housed at a wildlife rehabilitation centre in Perth, Western Australia. Sporulated oocysts of Isospora amphiboluri (n = 30) are spherical, 24.2 (26.5-23.0) µm in length and 23.9 (22.4-25.9) µm in width, with a shape index of 1.01. The bilayered oocyst wall is smooth and light-yellow in color. Polar granule, oocyst residuum and micropyle are absent. The sporocysts are lemon-shaped, 15.7 (15.2-18.0) × 10.2 (8.9-11.2) µm, with a shape index (length/width) of 1.53. Stieda and substieda bodies are present, the Stieda body being small and hemidome-shaped and the substieda half-moon-shaped. Each sporocyst contains four vermiform sporozoites arranged head to tail. The sporozoites are 11.7 (9.9-16.2) × 3.0 (2.4-3.5) µm, with a shape index (length/width) of 3.87. A sporocyst residuum is present. Sporozoites contain a central nucleus with a finely distributed granular residuum. Comparison of oocyst measurements and their features with other valid Isospora species from hosts in the Agamid family confirmed that this Isospora species is Isospora amphiboluri. Molecular characterization of I. amphiboluri at the 18S rRNA and MTCOI loci showed the highest similarity with I. amphiboluri from the central bearded dragon, 99.8% and 99.7% respectively. This is the first report of I. amphiboluri from a central netted dragon in Australia.
Subject(s)
Host-Parasite Interactions , Isospora/isolation & purification , Isosporiasis/veterinary , Lizards , Animals , Animals, Zoo , Electron Transport Complex IV/analysis , Isospora/classification , Isospora/cytology , Isospora/genetics , Isosporiasis/parasitology , Male , Mitochondrial Proteins/analysis , Oocysts/classification , Oocysts/cytology , Oocysts/isolation & purification , Phylogeny , Protozoan Proteins/analysis , RNA, Protozoan/analysis , RNA, Ribosomal, 18S/analysis , Sporozoites/classification , Sporozoites/cytology , Sporozoites/isolation & purification , Western AustraliaABSTRACT
Stable isotope labeling by amino acids in cell culture (SILAC) combined with high-resolution mass spectrometry is a quantitative strategy for the comparative analysis of (sub)proteomes. It is based on the metabolic incorporation of stable isotope-coded amino acids during growth of cells or organisms. Here, complete labeling of proteins with the amino acid(s) selected for incorporation needs to be guaranteed to enable accurate quantification on a proteomic scale. Wild-type strains of baker's yeast (Saccharomyces cerevisiae ), which is a widely accepted and well-studied eukaryotic model organism, are generally able to synthesize all amino acids on their own (i.e., prototrophic). To render them amenable to SILAC, auxotrophies are introduced by genetic manipulations. We addressed this limitation by developing a generic strategy for complete "native" labeling of prototrophic S. cerevisiae with isotope-coded arginine and lysine, referred to as "2nSILAC". It allows for directly using and screening several genome-wide yeast mutant collections that are easily accessible to the scientific community for functional proteomic studies but are based on prototrophic variants of S. cerevisiae.
Subject(s)
Mitochondrial Proteins/analysis , Proteome , Proteomics , Saccharomyces cerevisiae Proteins/analysis , Saccharomyces cerevisiae/metabolism , Tandem Mass Spectrometry , Chromatography, High Pressure Liquid , Gene Expression Regulation, Fungal , Isotope Labeling , Mitochondrial Proteins/genetics , Mutation , Research Design , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae Proteins/geneticsABSTRACT
Protein biotinylation via chemical or enzymatic reactions is often coupled with streptavidin-based enrichment and on-bead digestion in numerous biological applications. However, the popular on-bead digestion method faces major challenges of streptavidin contamination, overwhelming signals from endogenous biotinylated proteins, the lost information on biotinylation sites, and limited sequence coverage of enriched proteins. Here, we explored thiol-cleavable biotin as an alternative approach to elute biotinylated proteins from streptavidin-coated beads for both chemical biotinylation and biotin ligase-based proximity labeling. All possible amino acid sites for biotinylation were thoroughly evaluated in addition to the primary lysine residue. We found that biotinylation at lysine residues notably reduces the trypsin digestion efficiency, which can be mitigated by the thiol-cleavable biotinylation method. We then evaluated the applicability of thiol-cleavable biotin as a substrate for proximity labeling in living cells, where TurboID biotin ligase was engineered onto the mitochondrial inner membrane facing the mitochondrial matrix. As a proof-of-principle study, thiol-cleavable biotin-assisted TurboID proteomics achieved remarkable intraorganelle spatial resolution with significantly enriched proteins localized in the mitochondrial inner membrane and mitochondrial matrix.
Subject(s)
Biotin/chemistry , Mitochondrial Proteins , Proteomics/methods , Sulfhydryl Compounds/chemistry , Biotin/metabolism , Biotinylation , HEK293 Cells , HeLa Cells , Humans , Mitochondria/chemistry , Mitochondrial Proteins/analysis , Mitochondrial Proteins/chemistry , Mitochondrial Proteins/metabolism , Sulfhydryl Compounds/metabolismABSTRACT
BACKGROUND: Both the highly pathogenic avian influenza (HPAI) H5N1 and low pathogenic avian influenza (LPAI) H9N2 viruses have been reported to cross species barriers to infect humans. H5N1 viruses can cause severe damage and are associated with a high mortality rate, but H9N2 viruses do not cause such outcomes. Our purpose was to use proteomics technology to study the differential expression of mitochondrial-related proteins related to H5N1 and H9N2 virus infections. METHODS: According to the determined viral infection titer, A549 cells were infected with 1 multiplicity of infection virus, and the mitochondria were extracted after 24 h of incubation. The protein from lysed mitochondria was analyzed by the BCA method to determine the protein concentration, as well as SDS-PAGE (preliminary analysis), two-dimensional gel electrophoresis, and mass spectrometry. Differential protein spots were selected, and Western blotting was performed to verify the proteomics results. The identified proteins were subjected to GO analysis for subcellular localization, KEGG analysis for functional classification and signaling pathways assessment, and STRING analysis for functional protein association network construction. RESULTS: In the 2-D gel electrophoresis analysis, 227 protein spots were detected in the H5N1-infected group, and 169 protein spots were detected in the H9N2-infected group. Protein spots were further subjected to mass spectrometry identification and removal of redundancy, and 32 differentially expressed proteins were identified. Compared with the H9N2 group, the H5N1-infected group had 16 upregulated mitochondrial proteins and 16 downregulated proteins. The differential expression of 70-kDa heat shock protein analogs, short-chain enoyl-CoA hydratase, malate dehydrogenase, and ATP synthase was verified by Western blot, and the results were consistent with the proteomics findings. Functional analysis indicated that these differentially expressed proteins were primarily involved in apoptosis and metabolism. CONCLUSIONS: Compared with their expression in the H9N2 group, the differential expression of eight mitochondrial proteins in the H5N1 group led to host T cell activation, antigen presentation, stress response, ATP synthesis and cell apoptosis reduction, leading to higher pathogenicity of H5N1 than H9N2.
Subject(s)
Host Microbial Interactions , Influenza A Virus, H5N1 Subtype/immunology , Influenza A Virus, H9N2 Subtype/immunology , Mitochondria/genetics , Mitochondrial Proteins/genetics , Proteomics , A549 Cells , Animals , Chickens/virology , Humans , Influenza in Birds/virology , Mitochondria/chemistry , Mitochondria/immunology , Mitochondrial Proteins/analysis , Mitochondrial Proteins/immunologyABSTRACT
Objective: This study aimed to investigate the roles of MRPL27 in survival from cholangiocarcinoma patients in The Cancer Genome Atlas (TCGA) database. Methods: In TCGA-CHOL profile, MRPL27 gene expression and clinical data were obtained. Cox regression models were used to evaluate the potential links between MRPL27 and cholangiocarcinoma survival. Enrichment analysis of MRPL27 was conducted in Metascape and Gene Set Enrichment Analysis (GSEA) databases. Results: 36 cholangiocarcinoma patients were included in this analysis. MRPL27 mRNA was significantly upregulated in tumor tissues in cholangiocarcinoma patients including intrahepatic, distal and hilar/perihilar cholangiocarcinoma cases (all p < 0.01). Cholangiocarcinoma patients with high MRPL27 had worse overall survival (OS) and disease-free survival (DFS) compared to those with low MRPL27 (all p < 0.05). Univariate and multivariate Cox models indicated that MRPL27 should be a risk factor for the OS and DFS in cholangiocarcinoma patients (both p < 0.01). Bioinformatic analysis revealed that MRPL27 mainly involved in the processes of mitochondrial translation elongation, respiratory electron transport, ATP synthesis, and inner mitochondrial membrane organization. No mutations of MRPL27 were screened in cholangiocarcinoma patients. Conclusion: Upregulated in tumors, MRPL27 contributes to unfavorable survival in cholangiocarcinoma patients.
Subject(s)
Bile Duct Neoplasms/genetics , Biomarkers, Tumor/genetics , Cholangiocarcinoma/genetics , Mitochondrial Proteins/metabolism , Neoplasm Recurrence, Local/epidemiology , Ribosomal Proteins/metabolism , Aged , Bile Duct Neoplasms/mortality , Bile Duct Neoplasms/pathology , Bile Duct Neoplasms/therapy , Bile Ducts/pathology , Biomarkers, Tumor/analysis , Biomarkers, Tumor/metabolism , Cholangiocarcinoma/mortality , Cholangiocarcinoma/pathology , Cholangiocarcinoma/therapy , Computational Biology , Disease-Free Survival , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Mitochondrial Proteins/analysis , Mitochondrial Proteins/genetics , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Prognosis , Ribosomal Proteins/analysis , Ribosomal Proteins/genetics , Risk FactorsABSTRACT
All 225 Fasciola flukes obtained from domestic animals (73 cattle, 7 sheep and 1 pig) of 18 distinct geographic areas in Ecuador-South America, were identified as Fasciola hepatica, based on molecular analyses of nuclear pepck and pold genes, and mitochondrial nad1gene as well as the morphological observation of sperm within the seminal vesicles. Fasciola gigantica and parthenogenic Fasciola forms endemic to Asian countries were not found in this study, although zebu cattle and water buffalos have introduced into South America from Asia; this could be due to the absence of suitable intermediate host snails. The results of pepck analysis using multiplex PCR developed previously showed that 32 of the flukes could not be confirmed as F. hepatica, suggesting that the method is unreliable for the accurate discrimination of F. hepatica, and that pepck gene of the species consists of multiple loci, not a single locus. The results of genetic diversity, phylogenetic, and network analyses based on mitochondrial nad1 sequences suggest that F. hepatica populations in South America, including Ecuador, formed from the ancestral F. hepatica individuals introduced into the continent along with anthropogenic movement of livestock infected with the species.
Subject(s)
Fasciola hepatica/classification , Genetic Variation , Animals , Ecuador , Fasciola/classification , Fasciola/genetics , Fasciola/isolation & purification , Fasciola hepatica/genetics , Fasciola hepatica/isolation & purification , Helminth Proteins/analysis , Mitochondrial Proteins/analysis , PhylogenyABSTRACT
The Philopterus Complex includes several lineages of lice that occur on birds. The complex includes the genera Philopterus (Nitzsch, 1818; Psocodea: Philopteridae), Philopteroides (Mey, 2004; Psocodea: Philopteridae), and many other lineages that have sometimes been regarded as separate genera. Only a few studies have investigated the phylogeny of this complex, all of which are based on morphological data. Here we evaluate the utility of nuclear and mitochondrial loci for recovering the phylogeny within this group. We obtained phylogenetic trees from 39 samples of the Philopterus Complex (Psocodea: Philopteridae), using sequences of two nuclear (hyp and TMEDE6) and one mitochondrial (COI) marker. We evaluated trees derived from these genes individually as well as from concatenated sequences. All trees show 20 clearly demarcated taxa (i.e., putative species) divided into five well-supported clades. Percent sequence divergence between putative species (~5-30%) for the COI gene tended to be much higher than those for the nuclear genes (~1-15%), as expected. In cases where species are described, the lineages identified based on molecular divergence correspond to morphologically defined species. In some cases, species that are host generalists exhibit additional underlying genetic variation and such cases need to be explored by further future taxonomic revisions of the Philopterus Complex.
Subject(s)
Insect Proteins/analysis , Ischnocera/classification , Phylogeny , Animals , Cell Nucleus , Electron Transport Complex IV/analysis , Genetic Markers , Ischnocera/genetics , Mitochondrial Proteins/analysisABSTRACT
In anti-neutrophilic cytoplasmic antibody (ANCA)-associated vasculitis (AAV) genetic predisposition, ANCA autoantibodies, neutrophil extracellular traps (NETs), complement activation, and toll-like receptor signaling are implicated in AAV pathogenesis. Heat shock proteins (HSPs), a highly conserved group of small-sized molecular chaperones, take part in protein folding during cellular stress. Although HSPs were initially observed intracellularly, it has been shown that they can be secreted in the extracellular space and modulate the immune response in various autoimmune diseases including AAV. The scope of the present study is to investigate the role of heat shock protein 60 (HSP60) and 70 (HSP70) in the long renal effects in an ANCA vasculitis cohort. In this cohort of ANCA-associated vasculitis, 29 patients were followed up over 20 years. At diagnosis, immunohistochemistry was performed for HSP60 and HSP70 within the various nephron compartments. Higher renal HSP60 expression was associated with increased interstitial inflammatory infiltrates at diagnosis, while HSP70 expression was associated with a greater extent of interstitial fibrosis at diagnosis. Notably, intense tissue expression of HSP70 at the time of biopsy was associated with a worsened kidney survival. Renal HSP70 expression was associated with poor renal outcomes during long-term follow-up. This finding may indicate a role of HSPs in renal disease progression in ANCA vasculitis. Further validating studies are needed to verify a causative association between HSP70 expression and renal outcomes in ANCA-associated vasculitis.