Polyglutamyl peptides: a new class of inhibitors of type‐2 casein kinases

FEBS Letters

Borin, Gianfranco¹  Marchiori, Fernando¹  Pinna, Lorenzo A.²  Meggio, Flavio² 

[1] Centro di Studio sui Biopolimeri, CNR, Padova, Italy;Istituto di Chimica Biologica dell'Università, Via Marzolo 3, 35 100 Padova, Italy

关键词: Casein kinase-2;    Protein kinase;    Protein phosphorylation;    Polyglutamate;    Phosphorylation site;    Inhibitors of protein kinases;    Ck-TS;    casein kinase TS;    RII;    regulatory subunit of cAMP-dependent protein kinase;    type II;    SDS;    sodium dodecyl sulfate;   

DOI  :  10.1016/0014-5793(83)80762-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Casein kinase-TS (Ck-TS), a type-2 casein kinase purified from rat liver cytosol which phosphorylates seryl and threonyl residues N-terminal to acidic clusters, is specifically inhibited by polyglutamyl peptides which are ineffective both on type-1 casein kinase and on cAMP-dependent protein kinase. The inhibition is competitive toward the protein substrate and non-competitive toward ATP. Among the polyglutamates tested (Glu)₇₀ is the most effective (K _i 0.11 μM). (Glu)₁₀ and (Glu)₅ are also inhibitors, though less powerful than (Glu)₇₀, while (Glu)₃, (Glu)₂ and free glutamic acid up to 5 mM are ineffective. These results disclose the possibility that naturally occurring polypeptides containing long stretches of acidic residues may act as physiological inhibitors of type-2 casein kinases.

【 授权许可】

Unknown