Endoplasmic Reticulum Lipid Raft Associated Protein 2 (ERLIN2)

SPFH2 associated rapidly with activated IP3 receptors , which are substrates for the ERAD pathway, in various mammalian cell lines. A proportion of SPFH2 associated with several components of the ERAD pathway, and RNA interference-mediated depletion of SPFH2 inhibited polyubiquitination and degradation of IP3R1 and turnover of model ERAD substrates. The deduced 339- and 152-amino acid proteins share the first 141 N-terminal amino acids, then diverge. Both proteins have an N-glycosylation site and type-2 membrane topology, and the longer protein has a lysine- and glutamic acid-rich region. Northern blot analysis detected ubiquitous expression of 1.6- and 2.5-kb transcripts; a minor 4.4-kb transcript was also observed.