Identification of sds22 as an inhibitory subunit of protein phosphatase‐1 in rat liver nuclei

FEBS Letters

Dinischiotu, Anca¹  Bollen, Mathieu¹  Beullens, Monique¹  Stalmans, Willy¹ 

[1] Afdeling Biochemie, Faculteit Geneeskunde, Katholieke Universiteit Leuven, B-3000 Leuven, Belgium

关键词: Cell cycle;    Dephosphorylation;    Mitosis;    Protein phosphatase;    PP-1;    protein phosphatase-1;    PP-1C;    catalytic subunit of protein phosphatase-1;    PP-1Nsds22;    PP-1 containing sds22;    PP-2AC;    catalytic subunit of protein phosphatase-2A;   

DOI  :  10.1016/S0014-5793(96)01514-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

sds22 was originally identified in yeast as a regulator of protein phosphatase-1 that is essential for the completion of mitosis. We show here that a structurally related mammalian polypeptide (41.6 kDa) is part of a 260-kDa species of protein phosphatase-1. This holoenzyme, designated PP-1N_sds22, could be immunoprecipitated with sds22 antibodies and was retained by microcystin-Sepharose. PP-1N_sds22 is a latent phosphatase, but its activity could be revealed by the proteolytic destruction of the noncatalytic subunit(s). PP-1N_sds22 accounted for only 5–10% of the total activity of PP-1 in rat liver nuclear extracts. A synthetic 22-mer peptide, corresponding to a leucine-rich repeat of sds22, specifically inhibited the catalytic subunit of PP-1, showing that at least part of the latency stems from the interaction of the sds22 repeat(s) with PP-1_C.

【 授权许可】

Unknown