ADP-ribosyltransferase type A from turkey erythrocytes modifies actin at Arg-95 and Arg-372.
Turkey erythrocyte ADP-ribosyltransferase A catalyzes the transfer of ADP-ribose from NAD to both monomeric and polymeric skeletal muscle alpha-actin with the incorporation of 2 mol of ADP-ribose per mol of actin. In contrast, Clostridium perfringens iota toxin ADP-ribosylates only G-actin, with modification at arginine-177 [Vandekerckhove, J., et al. (1987) FEBS Lett. 255, 48-42]. Transferase A-catalyzed modifications are sensitive to 0.5 M neutral hydroxylamine, consistent with the arginine side chain modification. Radiolabeled peptides ADP-ribosylated by transferase A were generated by tryptic digestion and purified by reversed phase high-performance liquid chromatography. Amino acid sequence and molecular mass analysis identified the ADP-ribosylation sites as Arg-95 and Arg-372 of actin; both residues are located within subdomain-1 of the actin 3D structure [Kabsch, W., et al. (1990) Nature 347, 37-44]. ADP-ribosylation did not affect cytochalasin D-stimulated G-actin ATPase, the binding of actin to DNase I or to gelsolin, or the ability of actin to polymerize. Following ADP-ribosylation, however, a prolonged delay in polymerization was observed, consistent with a decreased rate of nucleation.
Just
I
I
Institut für Pharmakologie und Toxikologie, Universität des Saarlandes, Homburg/Saar, Germany.
Sehr
P
P
Jung
M
M
van Damme
J
J
Puype
M
M
Vandekerckhove
J
J
Moss
J
J
Aktories
K
K
D000199:Actins / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001120:Arginine / Q000378:metabolism; D001665:Binding Sites; D004912:Erythrocytes / Q000201:enzymology*; D006868:Hydrolysis; D008969:Molecular Sequence Data; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism*; D014422:Turkeys
D000199:Actins; D000255:Adenosine Triphosphate; D001120:Arginine; D011065:Poly(ADP-ribose) Polymerases