磷脂酰肌醇4,5 - 二磷酸刺激蛋白激酶C介导的可溶性脑蛋白磷酸化。新霉素的抑制作用。

Phosphatidylinositol 4,5-bisphosphate stimulates protein kinase C-mediated phosphorylation of soluble brain proteins. Inhibition by neomycin.

作者信息

Chauhan V P

机构信息

New York State Institute for Basic Research in Developmental Disabilities, Staten Island 10314.

出版信息

FEBS Lett. 1990 Oct 15;272(1-2):99-102. doi: 10.1016/0014-5793(90)80457-t.

DOI:10.1016/0014-5793(90)80457-t

PMID:2172022

Abstract

Phosphatidylinositol 4,5-bisphosphate (PIP2) at 0.1 mol% activated the protein kinase C (PKC)-mediated phosphorylation of 87-, 55- and 47-kDa brain proteins. Neomycin, an aminoglycoside antibiotic that binds PIP2 with a high affinity, inhibited PIP2.PKC activity in a concentration-dependent manner. Low concentrations of neomycin (less than 2 mM) did not affect DG.PKC activity; however, 4 mM neomycin inhibited 50% of this activity. This inhibition of DG-stimulated activity at high neomycin concentration may be the result of its binding to Ca2+ and ATP in the assay system. These results suggest that PIP2 is a physiological activator of PKC, and show that neomycin can be an inhibitor of PIP2.PKC activity at concentrations where DG.PKC activity is not affected.

摘要

0.1摩尔%的磷脂酰肌醇4,5 -二磷酸（PIP2）激活了蛋白激酶C（PKC）介导的87 kDa、55 kDa和47 kDa脑蛋白的磷酸化。新霉素是一种与PIP2具有高亲和力的氨基糖苷类抗生素，它以浓度依赖的方式抑制PIP2 - PKC活性。低浓度的新霉素（小于2 mM）不影响二酰甘油（DG） - PKC活性；然而，4 mM新霉素抑制了50%的该活性。高浓度新霉素对DG刺激活性的这种抑制可能是其与测定系统中的Ca2+和ATP结合的结果。这些结果表明PIP2是PKC的生理性激活剂，并表明在不影响DG - PKC活性的浓度下，新霉素可以是PIP2 - PKC活性的抑制剂。