Modification and Degradation of the C(6) Rat Glioma Cellulr HSP68 in Vitro and in Vivo.
The biological modification and degradation of C(6) in vitro and in vivo were analyzed with renaturation electrophoresis, Western blot and autoradiography. The results show: (1) the C(6) cellular neutral proteases hardly take part in HSP68 degradation; (2) HSP68 degradation involves cytosol ATP-binding proteases and lysosomal acidic proteases. The ATP-binding proteases play an important role in starting HSP68 degradation and in degrading HSP68 into large polypeptide fragments. The lysosomal acidic proteases are mainly involved in the complete degradation of the large polypeptide fragments; (3) while HSP68-gene is induced through heat shock to express HSP68, a gene is also induced to express 65 kD ATP-binding protease, which not only specifically degrade HSP68 but also modify it to have serine protease activity; (4) the degradation products of HSP68 in vivo are similar to those in vitro.
Xu
Cun-Shuan
CS
Henan Normal University, Province Key Laboratory of Biotechnology, Xinxiang 453002, China.
Ji
Ai-Ling
AL
Xia
Ming
M
Li
Yan-Zhang
YZ
Xiang
Hua
H