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Polypeptide Hormones and Chromatin‐Associated Proteins Act as Acceptors for Cholera Toxin‐Catalyzed ADP‐Ribosylation
Author(s) -
Trepel J. B.,
Chuang D.M.,
Neff N. H.
Publication year - 1981
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/j.1471-4159.1981.tb01625.x
Subject(s) - cholera toxin , adp ribosylation , biochemistry , protamine , protein subunit , nicotinamide , toxin , chemistry , biology , microbiology and biotechnology , nad+ kinase , enzyme , endocrinology , heparin , gene
Cholera toxin catalyzed the ADP‐ribosylation of the pituitary protein hormones thyrotropin (TSH), lutropin (LH), follitropin (FSH), human chorionic gonadotropin (hCG). and corticotropin (ACTH) 1–24 , and ADP‐ribosylation of the basic proteins histone subfraction H 1 and protamine. Casein and phosvitin, acidic nuclear proteins, did not act as acceptors for toxin‐catalyzed ADP‐ribosylation. The isolated TSH A and B subunits were tested for their ADP‐ribose acceptor activity. The TSH A subunit showed fourfold greater ADP‐ribose acceptor activity than the TSH B subunit. The ADP‐ribose acceptor protein protamine was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis following incubation with cholera toxin under ADP‐ribosylating conditions. [ 3 H]ADP‐ribose incorporated into protein from [ 3 H]NAD migrated with the acceptor protein protamine. In the absence of added acceptor protein, the [ 3 H]ADP‐ribose incorporated into protein migrated with the A 1 fragment of cholera toxin. Cholera toxin A and B subunits were isolated and tested for their ability to catalyze the transfer of ADP‐ribose to protamine. The cholera toxin A subunit showed 50‐fold greater ADP‐ribosyltransferase activity than the B subunit. Our data indicate that a variety of adenohypophyseal hormones and regulatory proteins act as acceptors for toxin‐catalyzed ADP‐ribosylation. These studies may help in understanding the role of endogenous ADP‐ribosyltransferases and the physiological effects of this modification of protein.