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 Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Combined Automated Annotation using Multiple IEA Methods
Selenophosphate synthetase genes from lung adenocarcinoma cells: Sps1 for recycling L-selenocysteine and Sps2 for selenite assimilation.
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Human Sps1 only weakly complements an E. coli selD mutant and requires added L-selenocysteine, supporting a selenium/selenocysteine salvage (recycling) role, in contrast to Sps2 which supports selenite assimilation.
"recycles l-selenocysteine, whereas the Sps2 enzyme can function with a"
Towards a proteome-scale map of the human protein-protein interaction network.
Human selenophosphate synthetase 1 has five splice variants with unique interactions, subcellular localizations and expression patterns.
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SPS1 has an arginine where SPS2 has the catalytic selenocysteine -- stated generically for SPS1, and true of Drosophila Sps1 (R49) but not of human SEPHS1, which carries threonine (T29). In vitro SPS1 does not synthesize selenophosphate while SPS2 does; SPS1 knockdown does not affect selenoprotein biosynthesis. SPS1 is implicated in oxidative-stress regulation and cell growth.
"In in vitro experiments, SPS2 synthesized SeP from selenide and ATP, but SPS1 did not have this activity"
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The major-type isoform localizes to plasma and nuclear membranes; the other variants are cytoplasmic. All variants homodimerize.
"MT was localized on both plasma and the nuclear membrane"
Next-generation sequencing to generate interactome datasets.
A proteome-scale map of the human interactome network.
Analysis of Novel Interactions between Components of the Selenocysteine Biosynthesis Pathway, SEPHS1, SEPHS2, SEPSECS, and SECp43.
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SEPHS1 forms oligomers with SEPHS2, SEPSECS and SECp43 in eukaryotic cells (BRET, co-IP), placing SEPHS1 in a cytoplasmic Sec-biosynthesis-associated complex.
"SEPHS1 and SEPHS2 form oligomers in eukaryotic cells"
The role of selenium-mediated redox signaling by selenophosphate synthetase 1 (SEPHS1) in hESCs.
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SEPHS1 regulates selenium-mediated redox signaling in human pluripotent stem cells; knockdown alters ROS-pathway/apoptosis genes and impairs reprogramming and single-cell survival.
"hSEPHS1 is a regulator of selenium-mediated redox-signaling"
A reference map of the human binary protein interactome.
Dual proteome-scale networks reveal cell-specific remodeling of the human interactome.
Zincore, an atypical coregulator, binds zinc finger transcription factors to control gene expression.
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SEPHS1 and QRICH1 form Zincore, a ZNF-specific transcription coregulator essential for embryonic development; a SEPHS1 arginine clamp recognizes DNA-bound zinc-finger domains and locks ZNFs (e.g. ZFP91) onto their cognate promoter motif to regulate transcription.
"recognition of different ZNFs and stabilizes ZFP91 onto its cognate DNA motif"
Cloning and functional characterization of human selenophosphate synthetase, an essential component of selenoprotein synthesis.
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Human selD (SEPHS1) was cloned; transfection increased selenium labeling of type-1 iodothyronine deiodinase and weakly complemented a bacterial selD mutant, and ATP/GTP-binding-domain point mutations altered ATP binding.
"reduced selenium labeling was due to altered ATP binding"
UniProt entry P49903 (SPS1_HUMAN), Zincore component SEPHS1
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UniProt frames SEPHS1 primarily as a core component of the Zincore transcription-coregulator complex that stabilizes zinc-finger transcription factors on DNA via an arginine clamp, with a role in redox homeostasis and an unclear/likely non-essential role in selenocysteine biosynthesis.
"acts as a molecular 'grip' to stabilize transcription factors at DNA-"