Phosphorylation and dephosphorylation in the proline-rich C-terminal domain of microtubule-associated protein 2.

TitlePhosphorylation and dephosphorylation in the proline-rich C-terminal domain of microtubule-associated protein 2.
Publication TypeJournal Article
Year of Publication1996
AuthorsSánchez, C., P. Tompa, K. Szücs, P. Friedrich, and J. Avila
JournalEur J Biochem
Volume241
Issue3
Pagination765-71
Date Published1996 Nov 1
ISSN0014-2956
KeywordsAnimals, Antibodies, Antibody Specificity, Brain Chemistry, Epitopes, Microtubule-Associated Proteins, Oligopeptides, Phosphoprotein Phosphatases, Phosphorylation, Proline, Proline-Directed Protein Kinases, Protein Phosphatase 1, Protein-Serine-Threonine Kinases, Rats
Abstract

The C-terminal domain of microtubule-associated protein 2 (MAP2) contains a proline-rich region and the tubulin-binding domain. We have generated antibodies to follow the phosphorylation state of the proline-rich domain. One of these antibodies (no. 305) has been raised against a synthetic peptide P (sequence RTPGTPGTPSY) phosphorylated at the threonine residues. This sequence is present in the proline-rich region of MAP2 and is phosphorylated in vitro by at least three different proline-directed protein kinases: p42mpk, p34cdc2, and GSK3 (glycogen-synthase kinase 3) alpha/beta. The MAP2 sites phosphorylated by these kinases are different, although all of them phosphorylate the C-terminal domain of MAP2 as determined by Staphylococcus aureus V8 protease mapping. Nonphosphorylated peptide P can be phosphorylated in vitro by all three kinases studied with similar efficiency. In high-molecular-mass MAP2, this sequence is highly phosphorylated in vivo at the late stages of rat development. This motif can be rapidly dephosphorylated in vitro by protein-phosphatase 1 (PP1) and 2A (PP2A) catalytic subunits but not by PP2B.

Alternate JournalEur. J. Biochem.
PubMed ID8944764