Biosynthesis and processing of pro‐C3, a precursor of the third component of complement in rat hepatocytes: effect of secretion‐blocking agents

FEBS Letters

Misumi, Yoshio¹  Ikehara, Yukio¹  Takami, Noboru¹ 

[1] Department of Biochemistry and Radioisotope Laboratory, Fukuoka Univerity School of Medicine, Nanakuma, Jonan-ku, Fukuoka 814-01, Japan

关键词: Complement C3;    Pro-form biosynthesis;    Proteolytic processing;    Cultured rat hepatocyte;    Colchicine;    Monensin;    C3;    the third component of complement;    SDS;    sodium dodecyl sulfate;    PAGE;    polyacrylamide gel electrophoresis;   

DOI  :  10.1016/0014-5793(84)80570-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Biosynthesis and intracellular processing of the third component (C3) of complement were studied in cultured rat hepatocytes. In the control cells, the complement C3 was synthesized as a pro-form, a single polypeptide chain comprising both the α- and β-subunits. Although the cleavage of the pro-form into the subunits was not clearly demonstrable within the cells during pulse-chase periods, all the secreted C3 was the mature processed form. The cells were treated with secretion-blocking agents with different modes of action, colchicine and monensin. Colchicine caused an accumulation of the processed C3 within the cells, whereas monensin blocked the secretion without a significant accumulation of the processed form. The results indicate that the conversion of the C3 pro-form into the subunits takes place in the secretory vesicles just before the secretion.

【 授权许可】

Unknown