Cholera Toxin can ADP-Ribosylate Gs as well as Gi in ACTH-Unresponsive Human Adrenocortical Cancer

Endocrine Journal

MASATOSHI NODA¹  MASAO OMURA⁴  AKIKO YOSHIDA³  HIRONOBU SASANO²  TETSUO NISHIKAWA⁴ 

[1] Second Department of Microbiology, Chiba University School of Medicine;The Department of Pathology, Tohoku University School of Medicine;Kanamachi Yoshida Clinic;Department of Medicine, Yokohama Rosai Hospital

关键词: Adrenocortical cancer;    ACTH-unresponsiveness;    Cholera toxin;    Gs;    Gi;   

DOI  :  10.1507/endocrj.41.593

学科分类：内分泌与代谢学

来源: Japan Endocrine Society

【 摘 要 】

References(6)Cited-By(3)It is well known that cholera toxin (CT) stimulates ADP-ribosylation of Gs and also pertussis toxin (PT) does Gi. Each GTP-binding protein has its own action in the regulation of adenylate cyclase. A human non-functioning adrenocortical cancer tissue showed an unresponsiveness in adenylate cyclase to ACTH although ACTH and CT activated adenylate cyclase in a non-functioning adrenal adenoma tissue. CT ADP-ribosylated 40kDa protein of the plasma membrane of the cancer tissue while CT and PT could ADP-ribosylate 43kDa and 38kDa protein in the adenoma tissue, respectively. Immunoblotting analysis of the cancer tissue demonstrated that 40kDa protein was detected by anti-Gs antibody as well as by anti-Gi antibody. The present experiments demonstrated that CT could ADP-ribosylate Gs which has stimulatory action on adenylate cyclase and also Gi which inhibits adenylate cyclase. Thus it is suggested that CT can activate the ADP-ribosylation of Gs and also Gi in a human adrenocortical cancer tissue, partly resulting in abnormal regulation of adenylate cyclase which may be crossly related to ACTH-unresponsiveness.

【 授权许可】

Unknown