Regulated co-translational ubiquitination of apolipoprotein B100: a new paradigm for proteasomal degradation of a secretory protein
M Zhou, EA Fisher, HN Ginsberg - Journal of Biological Chemistry, 1998 - ASBMB
Presentation of a wild-type secretory protein, apolipoprotein B100 (apoB), to the cytosol for
ubiquitin-proteasome proteolysis has been observed in HepG2 cells. A currently accepted
model for proteasomal degradation of secretory proteins is retrograde translocation of the
substrate polypeptides from the lumen of endoplasmic reticulum (ER) back to the cytosol. In
this report, we present evidence that newly synthesized apoB becomes exposed to the
cytosol and targeted to the proteasomes in a co-translational manner. Thus, after protein …
ubiquitin-proteasome proteolysis has been observed in HepG2 cells. A currently accepted
model for proteasomal degradation of secretory proteins is retrograde translocation of the
substrate polypeptides from the lumen of endoplasmic reticulum (ER) back to the cytosol. In
this report, we present evidence that newly synthesized apoB becomes exposed to the
cytosol and targeted to the proteasomes in a co-translational manner. Thus, after protein …
