Alternative titles; symbolsLSFR2, PUFFERFISH, HOMOLOG OF; LSFR2HGNC Approved Gene Symbol: DOLPP1Cytogenetic location: 9q34.11 Genomic coordinates (GRCh38): 9...
Alternative titles; symbols
HGNC Approved Gene Symbol: DOLPP1
Cytogenetic location: 9q34.11 Genomic coordinates (GRCh38): 9:129,080,987-129,090,437 (from NCBI)
Cotranslational N-glycosylation of nascent polypeptides in the endoplasmic reticulum (ER) requires the transfer of a complex oligosaccharide chain from its dolichyl pyrophosphate (Dol-P-P) carrier lipid to the nitrogen of an asparagine residue, concomitant with the release of Dol-P-P into the lumen of the ER. DOLPP1 (EC 188.8.131.52) converts Dol-P-P to dolichyl phosphate (Dol-P), which is subsequently translocated to the cytoplasmic leaflet of the ER for regeneration and participation in subsequent rounds of N-glycosylation (Rush et al., 2002).
▼ Cloning and Expression
Rush et al. (2002) obtained a mouse brain cDNA encoding Dolpp1. The deduced 238-amino acid protein has 4 putative transmembrane domains and a consensus lipid-phosphate phosphatase motif. The N and C termini are predicted to be on the cytosolic face of the ER, and the catalytic domain is predicted to be on the luminal face of the ER. Northern blot analysis detected a 2.0-kb transcript in all mouse tissues examined, with highest expression in brain, kidney, lung, and intestine. Sedimentation and immunofluorescence analyses revealed that Dolpp1 was expressed in the ER of transfected COS cells. Protease digestion studies suggested that the active site was oriented within the lumen of the ER.
▼ Gene Function
Rush et al. (2002) found that microsomes isolated from yeast or insect cells expressing mouse Dolpp1 readily dephosphorylated Dol-P-P to Dol-P, whereas Dol-P and phosphatidic acid were relatively poor substrates. Expression of mouse Dolpp1 complemented the defect in growth and protein N-glycosylation in yeast lacking Cwh8, the ortholog of Dolpp1. Overexpression of either Dolpp1 or Cwh8 in mutant yeast reversed the accumulation of Dol-P-P.
By radiation hybrid analysis and FISH, Gilley and Fried (1999) mapped the DOLPP1 gene to chromosome 9q34.1.