Enables mannosyltransferase activity. Involved in protein C-linked glycosylation via 2'-alpha-mannosyl-L-tryptophan. Located in perinuclear region of cytoplasm. Expressed in several structures, including P1; P2; QL; QR; and seam cell. Human ortholog(s) of this gene implicated in spermatogenic failure 9. Is an ortholog of human DPY19L2 (
dpy-19 like 2).