8.A.159.1.1
MARCH1 (MARCHF1; RNF171) of 189 aas and 2 TMSs near, but not at, the C-terninus. It is an E3 ubiquitin-protein ligase that mediates ubiquitination of the transferrin recpeotor (TFRC), CD86, FAS and MHC class II proteins, such as HLA-DR alpha and beta, and promotes their subsequent endocytosis and sorting to lysosomes via multivesicular bodies (Lapaque et al. 2009). By constitutively ubiquitinating MHC class II proteins in immature dendritic cells, it down-regulates their cell surface localizations, thus sequestering them in the intracellular endosomal system (De Gassart et al. 2008). It, and its orthologs, play roles in antiviral innate immunity (Zheng 2021) (see family description).