Human Gene PTDSS1 (ENST00000522072.1) Description and Page Index
Description: Catalyzes a base-exchange reaction in which the polar head group of phosphatidylethanolamine (PE) or phosphatidylcholine (PC) is replaced by L-serine. In membranes, PTDSS1 catalyzes mainly the conversion of phosphatidylcholine. Also converts, in vitro and to a lesser extent, phosphatidylethanolamine. (from UniProt P48651) RefSeq Summary (NM_001290225): The protein encoded by this gene catalyzes the formation of phosphatidylserine from either phosphatidylcholine or phosphatidylethanolamine. Phosphatidylserine localizes to the mitochondria-associated membrane of the endoplasmic reticulum, where it serves a structural role as well as a signaling role. Defects in this gene are a cause of Lenz-Majewski hyperostotic dwarfism. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Mar 2014]. Gencode Transcript: ENST00000522072.1 Gencode Gene: ENSG00000156471.13 Transcript (Including UTRs) Position: hg38 chr8:96,295,192-96,333,982 Size: 38,791 Total Exon Count: 10 Strand: + Coding Region Position: hg38 chr8:96,299,703-96,333,850 Size: 34,148 Coding Exon Count: 9
ID:PTSS1_HUMAN DESCRIPTION: RecName: Full=Phosphatidylserine synthase 1; Short=PSS-1; Short=PtdSer synthase 1; EC=184.108.40.206; AltName: Full=Serine-exchange enzyme I; FUNCTION: Catalyzes a base-exchange reaction in which the polar head group of phosphatidylethanolamine (PE) or phosphatidylcholine (PC) is replaced by L-serine. In membranes, PTDSS1 catalyzes mainly the conversion of phosphatidylcholine. Also converts, in vitro and to a lesser extent, phosphatidylethanolamine. CATALYTIC ACTIVITY: L-1-phosphatidylethanolamine + L-serine = L-1- phosphatidylserine + ethanolamine. ENZYME REGULATION: Requires calcium ions. Activated by exogenous phosphatidylethanolamine. BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=67 uM for serine (in the presence of 2 mM PC); KM=24 uM for serine (in the presence of 1 mM PE); pH dependence: Optimum pH for both PC and PE is between 7.0 and 7.5; PATHWAY: Phospholipid metabolism; phosphatidylserine biosynthesis. SUBCELLULAR LOCATION: Endoplasmic reticulum membrane; Multi-pass membrane protein (By similarity). Note=Highly enriched in the mitochondria-associated membrane (MAM) (By similarity). SIMILARITY: Belongs to the phosphatidyl serine synthase family.
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
ModBase Predicted Comparative 3D Structure on P48651
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Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.