BIP IS A SUBSTRATE FOR SRC KINASE IN-VITRO

In a study to investigate the ability of chaperones to modulate src ki nase activity, it was observed that BiP, a member of the HSP70 family found in the endoplasmic reticulum, is an excellent substrate for src kinase in vitro. The reaction requires polylysine and the results sugg est that two tyrosine residues are phosphorylated. Although there is n o evidence for this reaction invivo, it does provide a very efficient method to label BiP. (C) 1994 Academic Press, Inc.