Dephosphorylation of distinct sites on microtubule‐associated protein MAP1B by protein phosphatases 1, 2A and 2B

FEBS Letters

Friedrich, Peter³  Dombrádi, Viktor¹  Szücs, Kornélia¹  Díaz-Nido, Javier²  Gergely, Pál¹  Ulloa, Luis²  Avila, Jesus² 

[1] Department of Medical Chemistry, University School of Medicine, Bem tér 18/ B, 4026-Debrecen, Hungary;Centro de Biologia Molecular (CSIC-UAM), Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain;Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, P.O.Box 7, 1518-Budapest, Hungary

关键词: Phosphorylation/dephosphorylation;    Microtubule-associated protein;    Protein phosphatase 1 and 2A;    Calcineurin;    Proline direct protein kinase (PDPK);    CaScin kinase II (CKII);   

DOI  :  10.1016/0014-5793(93)80925-K

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Rat brain microtubule-associated protein MAP1 B has been tested as a substrate for Ser/Thr protein phosphatases (PP). The dephosphorylation reactions were followed by specific antibodies recognizing phosphorylated and phosphorylatable epitopes. One set of phosphorylation sites on MAPI B are referred to as mode I sites, and their phosphorylation is presumably catalyzed by proline-directed protein kinases. These mode I sites are efficiently dephosphorylated by PP2B and 2A but not by PP1. Another set of phosphorylation sites on MAP1B are named mode II sites, and their phosphorylation is possibly due to casein kinase II. These mode II sites are dephosphorylated by PP2A and PP1, the PP2B being ineffective. The selectivity of phosphatases for different sites within the same protein indicates the complexity of the dephosphorylation reactions regulating the functionality of MAP1B in neurons.

【 授权许可】

Unknown