Reduction of adenylyl cyclase activity by cholera toxin in myeloid cells

FEBS Letters

Hermouet, S.¹  Milligan, G.²  Lanotte, M.¹ 

[1] INSERM U301, Hôpital Saint-Louis, Paris, France;Department of Biochemistry, University of Glasgow, Glasgow, UK

关键词: Adenylyl-cyclase;    GTP-binding protein;    Down-regulation;    CT;    cholera toxin;    PT;    pertussis toxin;    CTs cells;    cholera toxin-sensitive cells;    CTr cells;    cholera toxin-resistant cells;    AC;    adenylyl-cyclase;    SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis;   

DOI  :  10.1016/0014-5793(90)80929-D

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In IPC-81 cells, the adenylyl-cyclase activation by cholera toxin produces an elevation of cAMP that causes a rapid cytolysis. A resistant clone with deficient cholera toxin-induced cyclase activity (yet sensitive to cAMP) showed a rapid decrease in the amount of membrane-bound Gsα (42–47 kDa) detectable soon after ADP-ribosylation of these proteins; pertussis toxin-sensitive G proteins (41 kDa) were not affected. Resistant cells showed a rapid decrease of Gsα that is consistent with the finding that cAMP did not accumulate in these cells. Cholera toxin treatment of resistant cells had long-lasting effects (several weeks) on the level of Gsα in the cell membrane. The duration of Gsα decrease does not correspond to the probable life of catalytically active cholera toxin in the cells, and suggests a regulated process more complex than a proteolytic degradation targeted on ADP-ribosylated molecules.

【 授权许可】

Unknown