POMT1

Protein O-mannosyl-transferase 1 is an enzyme that in humans is encoded by the POMT1 gene.^[4][5] It is a member of the dolichyl-phosphate-mannose-protein mannosyltransferases.

POMT1
Identifiers
Aliases	POMT1, LGMD2K, MDDGA1, MDDGB1, MDDGC1, RT, protein O-mannosyltransferase 1
External IDs	OMIM: 607423; MGI: 2138994; HomoloGene: 68548; GeneCards: POMT1; OMA:POMT1 - orthologs
Gene location (Mouse) Chr. Chromosome 2 (mouse)[1] Band 2|2 B Start 32,236,590 bp[1] End 32,255,005 bp[1]
RNA expression pattern Bgee Human Mouse (ortholog) n/a Top expressed in spermatocyte spermatid seminiferous tubule crypt of lieberkuhn of small intestine brown adipose tissue proximal tubule masseter muscle neural layer of retina right kidney intercostal muscle BioGPS More reference expression data
Gene ontology Molecular function glycosyltransferase activity dolichyl-phosphate-mannose-protein mannosyltransferase activity transferase activity mannosyltransferase activity metal ion binding Cellular component integral component of membrane acrosomal vesicle endoplasmic reticulum sarcoplasmic reticulum membrane endoplasmic reticulum membrane Biological process multicellular organism development protein glycosylation protein O-linked glycosylation extracellular matrix organization protein O-linked mannosylation ER-associated misfolded protein catabolic process mannosylation positive regulation of protein O-linked glycosylation carbohydrate metabolic process Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 10585 99011 Ensembl ENSG00000130714 ENSMUSG00000039254 UniProt Q9Y6A1 Q5JT04 Q8R2R1 RefSeq (mRNA) NM_001077365 NM_001077366 NM_001136113 NM_001136114 NM_007171 NM_145145 RefSeq (protein) NP_001070833 NP_001070834 NP_001129585 NP_001129586 NP_009102 NP_001340122 NP_001340123 NP_001340124 NP_001340125 NP_001340126 NP_001340127 NP_001340128 NP_001340129 NP_001361618 NP_001361619 NP_001361620 NP_001361621 NP_001361622 NP_001361624 NP_660127 Location (UCSC) n/a Chr 2: 32.24 – 32.26 Mb PubMed search [2] [3]
Wikidata
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Function

O-mannosylation is an important protein modification in eukaryotes that is initiated by an evolutionarily conserved family of protein O-mannosyltransferases. POMT1 shares sequence similarity with protein O-mannosyltransferases of S. cerevisiae. In yeast, these enzymes are located in the endoplasmic reticulum (ER) and are required for cell integrity and cell wall rigidity. POMT1 also shows similarity to the Drosophila 'rotated abdomen' (rt) gene, which when mutated causes defects in myogenesis and muscle structure.[supplied by OMIM]^[5]

It is associated with limb-girdle muscular dystrophy type LGMD2K.^[6]

In the retina it is known that O-mannosylation of α-DG carried out by POMT1 is crucial for the establishment of proper synapses at the outer plexiform layer and the transmission of visual information from cones and rods to their postsynaptic neurons, i.e. bipolar and horizontal cells.^[7] Lack of POMT1 expression results in a good number of impairments in photoreceptors that have been documented at the proteomic, morphological and physiological levels.^[7][8]