GPI mannosyltransferase 4 (GPI-MT-4, phosphatidylinositol-glycan biosynthesis class Z protein, PIG-Z, hSMP3, PIGZ, SMP3)

Function

• mannosyltransferase
• glycosylphosphatidylinositol-anchor biosynthesis.
• transfers 4th mannose to some trimannosyl-GPIs during GPI precursor assembly
• presence of a 4th mannose in GPI is facultative & only scarcely detected, suggesting that it only exists in some tissues
• glycolipid biosynthesis

glycosylphosphatidylinositol-anchor biosynthesis

Structure

• belongs to the glycosyltransferase 22 family, PIGZ subfamily

Compartment

endoplasmic reticulum membrane

Expression

• widely expressed at low level
• highest level in brain & colon

More general terms

• transmembrane 6 protein
• GPI mannosyltransferase

Database

• UniProt: http://www.uniprot.org/uniprot/Q86VD9.html