Gene Ontology annotation through association of InterPro records with GO terms
Manual transfer of experimentally-verified manual GO annotation data to orthologs by curator judgment of sequence similarity
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword mapping
Gene Ontology annotation based on curation of immunofluorescence data
Automatic transfer of experimentally verified manual GO annotation data to orthologs using Ensembl Compara
Combined Automated Annotation using Multiple IEA Methods
Frataxin interacts functionally with mitochondrial electron transport chain proteins.
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Human frataxin physically interacts with human succinate dehydrogenase complex subunits including SDHB, suggesting a key role of frataxin in the mitochondrial electron transport chain.
"We also demonstrate a physical interaction between human frataxin and human succinate dehydrogenase complex subunits, suggesting also a key role of frataxin in the mitochondrial electron transport chain in humans"
LC-MS/MS as an alternative for SDS-PAGE in blue native analysis of protein complexes.
Human complex II (succinate-ubiquinone oxidoreductase): cDNA cloning of iron sulfur (Ip) subunit of liver mitochondria.
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First cDNA cloning of the human iron-sulfur subunit (SDHB) of Complex II from liver mitochondria. The mature protein is 252 amino acids with striking conservation of three cysteine-rich clusters comprising the iron-sulfur centers.
"Complex II (succinate-ubiquinone oxidoreductase) is an important enzyme complex of both the tricarboxylic acid cycle and of the aerobic respiratory chains of mitochondria in eukaryotic cell and prokaryotic organisms"
Cochaperone binding to LYR motifs confers specificity of iron sulfur cluster delivery.
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SDHB contains two LYR motifs that engage the ISCU-HSC20-HSPA9 Fe-S transfer complex to aid incorporation of its three Fe-S clusters. Assembly factor SDHAF1 also associates with SDHB and uses its own LYR motif to position an additional Fe-S transfer complex near SDHB.
"In succinate dehydrogenase B, two LYR motifs engage the ISCU-HSC20-HSPA9 complex to aid incorporation of three Fe-S clusters within the final structure of complex II"
Disease-Causing SDHAF1 Mutations Impair Transfer of Fe-S Clusters to SDHB.
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SDHAF1 contributes to Fe-S cluster incorporation into SDHB by transiently binding to SDHB through an arginine-rich region and engaging the Fe-S donor complex. Disease- causing SDHAF1 mutations abrogate binding to SDHB, impairing holo-SDHB biogenesis.
"SDHAF1 contributes to iron-sulfur (Fe-S) cluster incorporation into the Fe-S subunit of CII, SDHB. SDHAF1 transiently binds to aromatic peptides of SDHB through an arginine-rich region in its C terminus"
Mitochondrial leukoencephalopathy and complex II deficiency associated with a recessive SDHB mutation with reduced penetrance.
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Homozygous SDHB p.Asp48Val mutation causes mitochondrial leukoencephalopathy with complex II deficiency. Spectrophotometric assays showed reduced succinate-ubiquinone reductase and SDH activities in muscle and fibroblasts. Immunoblot showed strongly decreased SDHB protein levels.
"Reduction of cII (succinate-ubiquinone reductase) and SDH activities were documented both on muscle tissue and skin fibroblasts"
Leukoencephalopathy due to Complex II Deficiency and Bi-Allelic SDHB Mutations: Further Cases and Implications for Genetic Counselling.
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Two additional patients with respiratory chain deficiency due to bi-allelic SDHB mutations, confirming the specific neuroradiological presentation of complex II deficiency. One SDHB mutation was previously described in heterozygous form in paraganglioma/pheochromocytoma patients.
"Isolated complex II deficiency is a rare cause of mitochondrial disease and bi-allelic mutations in SDHB have been identified in only a few patients with complex II deficiency and a progressive neurological phenotype with onset in infancy"
A Single Adaptable Cochaperone-Scaffold Complex Delivers Nascent Iron-Sulfur Clusters to Mammalian Respiratory Chain Complexes I-III.
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The cochaperone HSC20 is essential for Fe-S cluster biogenesis of SDHB and also delivers Fe-S clusters to Complex I and Complex III subunits, highlighting the crucial role of the cochaperone-scaffold complex in respiratory chain assembly.
"Recent studies have shown that the co-chaperone HSC20, essential for Fe-S cluster biogenesis of SDHB, directly binds LYRM7"
Architecture of the human interactome defines protein communities and disease networks.
Assembly of mammalian oxidative phosphorylation complexes I-V and supercomplexes.
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Review of OXPHOS complex assembly. Complex II comprises SDHA, SDHB, SDHC, SDHD. Assembly involves FAD insertion into SDHA by SDHAF2, Fe-S cluster incorporation into SDHB, then SDHA-SDHB dimerization and insertion into the membrane via SDHC-SDHD.
"The assembly of the five oxidative phosphorylation system (OXPHOS) complexes in the inner mitochondrial membrane is an intricate process"
Dual proteome-scale networks reveal cell-specific remodeling of the human interactome.
Quantitative high-confidence human mitochondrial proteome and its dynamics in cellular context.
Systematic discovery of mutation-directed neo-protein-protein interactions in cancer.
Structure of the human respiratory complex II.
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Cryo-EM structure of human Complex II at 2.86 angstroms resolution showing all four subunits (SDHA, SDHB, SDHC, SDHD) with FAD, three Fe-S clusters, heme b, and ubiquinone. SDHB is a small iron-sulfur protein harboring [2Fe-2S], [4Fe-4S], and [3Fe-4S] clusters organized into two domains in a butterfly-like shape. The electron transfer pathway from FAD through Fe-S clusters to ubiquinone is proposed. SDHB residues Pro197, Trp201, and Ile246 directly contact ubiquinone.
"SDHB contains two domains: the N-terminal domain (residues A35 to A142) and the C-terminal domain (residues A143 to A273)"
SDH complex dehydrogenates succinate
Transfer of Fe-S clusters to SDHB
SDHA:SDHB binds to SDHC:SDHD
Deep research review of SDHB gene function (Falcon provider)