Limited caspase cleavage of human BAP31

Human BAP31 was cleaved at both of its two identical caspase cleavage sites in two previously reported models of apoptosis, We show here that only the most carboxy-terminal site is cleaved during apoptosis induced in HeLa cel ls by tunicamycin, tumor necrosis factor and cycloheximide, or staurosporin e. Similar results were obtained in HL-60 cells using Fas/APO-1 antibodies, or cycloheximide. This limited cleavage, which is inhibited by several cas pase inhibitors, removes eight amino acids from human BAP31 including the K KXX coat protein I binding motif, Ectopic expression of the resulting cleav age product induces redistribution of mannosidase II from the Golgi and pre vents endoplasmic reticulum to Golgi transport of virus glycoproteins. (C) 2000 Federation of European Biochemical Societies. Published by Elsevier Sc ience B.V, All rights reserved.