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
Cloning and sequencing of the yeast gene for dolichol phosphate mannose synthase, an essential protein.
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Yeast DPM1 is the structural gene for Dol-P-Man synthase; it confers activity on E. coli.
"DPM1 is the structural gene for yeast Dol-P-Man synthase since Escherichia coli transformants harboring this gene express Dol-P-Man synthase activity in vitro"
Dolichol phosphate mannose synthase is required in vivo for glycosyl phosphatidylinositol membrane anchoring, O mannosylation, and N glycosylation of protein in Saccharomyces cerevisiae.
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Yeast dpm1 ts mutants are blocked in GPI anchoring, N-glycosylation and O-mannosylation.
"is required in vivo for all three biosynthetic pathways leading to these covalent"
Human and Saccharomyces cerevisiae dolichol phosphate mannose synthases represent two classes of the enzyme, but both function in Schizosaccharomyces pombe.
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DPM synthases fall into a yeast class with a C-terminal hydrophobic anchor and a human class lacking it; a Caenorhabditis (C. briggsae) synthase is human-class, and the classes are functionally interchangeable.
"the other contains the human, S. pombe , and Caenorhabditis synthases, which lack a hydrophobic COOH-terminal domain"
A homologue of Saccharomyces cerevisiae Dpm1p is not sufficient for synthesis of dolichol-phosphate-mannose in mammalian cells.
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Mammalian DPM1 lacks the yeast transmembrane domain and requires another gene product for Dol-P-Man synthesis.
"lacking a hydrophobic transmembrane domain, which exists in the yeast synthase"
Human dolichol-phosphate-mannose synthase consists of three subunits, DPM1, DPM2 and DPM3.
DPM1, the catalytic subunit of dolichol-phosphate mannose synthase, is tethered to and stabilized on the endoplasmic reticulum membrane by DPM3.
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DPM3 tethers the anchor-less human DPM1 to the ER membrane.
"A coiled-coil domain near the C terminus of DPM3 was important for tethering DPM1, the catalytic subunit of the enzyme, to the endoplasmic reticulum membrane"
UniProtKB entry Q9TYJ7 (Q9TYJ7_CAEEL)
dpm-1 (Q9TYJ7) sequence and family checks