UniProt functional annotation for Q9HD40



	UniProt functional annotation for Q9HD40

UniProt code: Q9HD40.

Organism: Homo sapiens (Human).

Taxonomy: Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.

Function: Converts O-phosphoseryl-tRNA(Sec) to selenocysteinyl- tRNA(Sec) required for selenoprotein biosynthesis. {ECO:0000269|PubMed:17142313}.

Catalytic activity: Reaction=H2O + O-phospho-L-seryl-tRNA(Sec) + selenophosphate = L- selenocysteinyl-tRNA(Sec) + 2 phosphate; Xref=Rhea:RHEA:25041, Rhea:RHEA-COMP:9743, Rhea:RHEA-COMP:9947, ChEBI:CHEBI:15377, ChEBI:CHEBI:16144, ChEBI:CHEBI:43474, ChEBI:CHEBI:78551, ChEBI:CHEBI:78573; EC=2.9.1.2; Evidence={ECO:0000269|PubMed:17142313};

Cofactor: Name=pyridoxal 5'-phosphate; Xref=ChEBI:CHEBI:597326; Evidence={ECO:0000269|PubMed:17142313, ECO:0000269|PubMed:19608919};

Pathway: Aminoacyl-tRNA biosynthesis; selenocysteinyl-tRNA(Sec) biosynthesis; selenocysteinyl-tRNA(Sec) from L-seryl-tRNA(Sec) (archaeal/eukaryal route): step 2/2. {ECO:0000269|PubMed:17142313}.

Subunit: Homotetramer formed by a catalytic dimer and a non-catalytic dimer serving as a binding platform that orients tRNASec for catalysis. Each tetramer binds the CCA ends of two tRNAs which point to the active sites of the catalytic dimer. {ECO:0000269|PubMed:19608919}.

Subcellular location: Cytoplasm {ECO:0000305}.

Tissue specificity: Primarily expressed in liver, pancreas, kidney and lung. Overexpressed in PHA-stimulated T-cells.

Disease: Pontocerebellar hypoplasia 2D (PCH2D) [MIM:613811]: A disorder characterized by postnatal onset of progressive atrophy of the cerebrum and cerebellum, microcephaly, profound mental retardation, spasticity, and variable seizures. {ECO:0000269|PubMed:20920667, ECO:0000269|PubMed:26115735}. Note=The disease is caused by variants affecting the gene represented in this entry.

Miscellaneous: Possible diagnostic marker for autoimmune hepatitis (AIH).

Miscellaneous: [Isoform 2]: May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. {ECO:0000305}.

Similarity: Belongs to the SepSecS family. {ECO:0000305}.

Sequence caution: Sequence=AAD33963.2; Type=Erroneous translation; Note=Wrong choice of CDS.; Evidence={ECO:0000305}; Sequence=AAH23539.1; Type=Erroneous translation; Note=Wrong choice of CDS.; Evidence={ECO:0000305}; Sequence=CAB62209.1; Type=Erroneous initiation; Note=Extended N-terminus.; Evidence={ECO:0000305}; Sequence=CAB89517.1; Type=Frameshift; Evidence={ECO:0000305};

Annotations taken from UniProtKB at the EBI.


Organism:		Homo sapiens (Human).
Taxonomy:		Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.



Function:		Converts O-phosphoseryl-tRNA(Sec) to selenocysteinyl- tRNA(Sec) required for selenoprotein biosynthesis. {ECO:0000269\|PubMed:17142313}.


Catalytic activity:		Reaction=H2O + O-phospho-L-seryl-tRNA(Sec) + selenophosphate = L- selenocysteinyl-tRNA(Sec) + 2 phosphate; Xref=Rhea:RHEA:25041, Rhea:RHEA-COMP:9743, Rhea:RHEA-COMP:9947, ChEBI:CHEBI:15377, ChEBI:CHEBI:16144, ChEBI:CHEBI:43474, ChEBI:CHEBI:78551, ChEBI:CHEBI:78573; EC=2.9.1.2; Evidence={ECO:0000269\|PubMed:17142313};
Cofactor:		Name=pyridoxal 5'-phosphate; Xref=ChEBI:CHEBI:597326; Evidence={ECO:0000269\|PubMed:17142313, ECO:0000269\|PubMed:19608919};
Pathway:		Aminoacyl-tRNA biosynthesis; selenocysteinyl-tRNA(Sec) biosynthesis; selenocysteinyl-tRNA(Sec) from L-seryl-tRNA(Sec) (archaeal/eukaryal route): step 2/2. {ECO:0000269\|PubMed:17142313}.
Subunit:		Homotetramer formed by a catalytic dimer and a non-catalytic dimer serving as a binding platform that orients tRNASec for catalysis. Each tetramer binds the CCA ends of two tRNAs which point to the active sites of the catalytic dimer. {ECO:0000269\|PubMed:19608919}.
Subcellular location:		Cytoplasm {ECO:0000305}.
Tissue specificity:		Primarily expressed in liver, pancreas, kidney and lung. Overexpressed in PHA-stimulated T-cells.
Disease:		Pontocerebellar hypoplasia 2D (PCH2D) [MIM:613811]: A disorder characterized by postnatal onset of progressive atrophy of the cerebrum and cerebellum, microcephaly, profound mental retardation, spasticity, and variable seizures. {ECO:0000269\|PubMed:20920667, ECO:0000269\|PubMed:26115735}. Note=The disease is caused by variants affecting the gene represented in this entry.
Miscellaneous:		Possible diagnostic marker for autoimmune hepatitis (AIH).
Miscellaneous:		[Isoform 2]: May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. {ECO:0000305}.
Similarity:		Belongs to the SepSecS family. {ECO:0000305}.
Sequence caution:		Sequence=AAD33963.2; Type=Erroneous translation; Note=Wrong choice of CDS.; Evidence={ECO:0000305}; Sequence=AAH23539.1; Type=Erroneous translation; Note=Wrong choice of CDS.; Evidence={ECO:0000305}; Sequence=CAB62209.1; Type=Erroneous initiation; Note=Extended N-terminus.; Evidence={ECO:0000305}; Sequence=CAB89517.1; Type=Frameshift; Evidence={ECO:0000305};