CREB3L3 at the Golgi membrane is cleaved in the luminal domain (LLarena et al. 2010) by MBTPS1 (S1P) (Bailey et al. 2007, inferred from mouse homologs in Zhang et al. 2006). By inference from cleavage of SREBFs (SREBPs), CREB3L3 is believed to be cleaved at a RTLH motif at amino acid residue 364.
serine-type endopeptidase activity of MBTPS1 [Golgi membrane]