TY - JOUR
T1 - Cutting edge
T2 - Proteasome involvement in the degradation of unassembled Ig light chains
AU - O'Hare, Thomas
AU - Wiens, Gregory D.
AU - Whitcomb, Elizabeth A.
AU - Enns, Caroline A.
AU - Rittenberg, Marvin B.
N1 - Copyright:
Copyright 2007 Elsevier B.V., All rights reserved.
PY - 1999/7/1
Y1 - 1999/7/1
N2 - Several studies on disposal of nonsecreted Ig L chains have identified the endoplasmic reticulum as the site of degradation. Here, we examine degradation of a nonsecreted Ig L chain, T15L, and an experimentally endoplasmic reticulum-retained secretion-competent L chain, D16L, in the absence of H chains. We demonstrate that 1) degradation is specifically impaired by the proteasome-specific inhibitors carboxybenzyl-leucyl-leucyl- leucine vinyl sulfone (Z-L3VS) and lactacystin, 2) L chain degradation occurs early in the biosynthetic pathway, and 3) degradation does not require vesicular transport. Our findings indicate that previous assertions of L chain disposal within the endoplasmic reticulum must be modified. To our knowledge, we provide the first direct evidence supporting a new paradigm for removal of nonsecreted Ig L chains via dislocation to cytosolic proteasomes.
AB - Several studies on disposal of nonsecreted Ig L chains have identified the endoplasmic reticulum as the site of degradation. Here, we examine degradation of a nonsecreted Ig L chain, T15L, and an experimentally endoplasmic reticulum-retained secretion-competent L chain, D16L, in the absence of H chains. We demonstrate that 1) degradation is specifically impaired by the proteasome-specific inhibitors carboxybenzyl-leucyl-leucyl- leucine vinyl sulfone (Z-L3VS) and lactacystin, 2) L chain degradation occurs early in the biosynthetic pathway, and 3) degradation does not require vesicular transport. Our findings indicate that previous assertions of L chain disposal within the endoplasmic reticulum must be modified. To our knowledge, we provide the first direct evidence supporting a new paradigm for removal of nonsecreted Ig L chains via dislocation to cytosolic proteasomes.
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M3 - Article
C2 - 10384092
AN - SCOPUS:0033168160
SN - 0022-1767
VL - 163
SP - 11
EP - 14
JO - Journal of Immunology
JF - Journal of Immunology
IS - 1
ER -