Calmodulin is a potent target for new hypothalamic neuropeptides

FEBS Letters

Ovádi, J.¹  Horv́ath, L.¹  Barkhudaryan, N.²  Galoyan, A.A.² 

[1]Institute ofEnzymology, Biological Research Center, Hung. Acad. Sci, PO Box 7, H-1518, Budapest, Hungary

[2]Institute of Biochemistry, Acad. Sci. SSR, Yerevan 375044, USSR

关键词: Anti-CaM activity;    Neuropeptide;    Enzyme-linked immunosorbent assay;    Cooperative binding;    CaM;    calmodulin;    TFP;    trifluoperazine;    ELISA;    enzyme-linked immunosorbent assay;    MLCK;    myosin light chain kinase;    PDE;    phosphodiesterase;    IgG;    immunoglobulin;   

DOI  :  10.1016/0014-5793(90)80541-P

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Recently, five glycopeptides with coronaro-constrictory properties were isolated from bovine hypothalamus [(1988) Neurochemistry (USSR) 7, 519-524]. Calmodulin has been recognized in our laboratory as a target protein for the neuropeptides isolated from hypothalamus. The results of indirect enzyme-linked immunosorbent assay have shown that the new hypothalamic neuropeptides antagonize with the monospecific anti-calmodulin antibody for Calmodulin binding although they are not fragments of Calmodulin. The inhibitory potency of the peptides is dependent on their concentration and the length of the polypeptide chain. Four out of five peptides are effective in nM concentration range. Ca²⁺ stimulates the binding of peptides to calmodulin; however, immunocomplex can be formed in the absence of Ca²⁺ as well. The effects of trifluoperazine and peptides on the calmodulin/antibody interaction are not additive, suggesting the cooperativity between the binding sites on calmodulin. Under physiological conditions the presence of the peptides could produce distinct conformers of calmodulin which may exhibit altered potency for stimulation/inhibition of target enzymes.

【 授权许可】

Unknown