Some common properties between a brain protein that is modified by posttranslational arginylation and the microtubule-associated STOP protein

• Published in: Journal of neurochemistry Vol. 63; no. 6; p. 2295
• Main Authors: Bongiovanni, G, Barra, H S, Hallak, M E
• Format: Journal Article
• Language: English
• Published: England 01-12-1994
• Subjects: Animals; Arginine - metabolism; Brain - ultrastructure; Brain Chemistry; Calmodulin - metabolism; Cold Temperature; Electrophoresis, Polyacrylamide Gel; Immunosorbent Techniques; Microtubule-Associated Proteins - immunology; Microtubule-Associated Proteins - metabolism; Microtubules - metabolism; Nerve Tissue Proteins - metabolism; Protein Processing, Post-Translational; Rats
• ISSN: 0022-3042
• DOI: 10.1046/j.1471-4159.1994.63062295.x

Properties so far studied of the 125-kDa 14C-arginylated protein from rat brain show remarkable similarities with those of the STOP (stable tubule only polypeptide) protein. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis the 125-kDa 14C-arginylated protein moves to the same position as the STOP protein. The 125-kDa 14C-arginylated protein was immunoprecipitated by the monoclonal Mab 296 antibody specific for neuronal STOP protein. The 125-kDa 14C-arginylated protein was retained by a calmodulin column like STOP protein. As occurs with the STOP protein, the 125-kDa 14C-arginylated protein is found in higher proportion in cold-stable than in cold-labile microtubules. However, the modified protein associates with microtubules in a lower proportion than the STOP protein. We conclude that the STOP protein incorporates arginine by a posttranslational reaction but that only a small fraction of the STOP protein shows acceptor capacity in vitro.