人巨核母细胞白血病细胞系（MEG-01）的蛋白激酶C。亚类分析以及二酰基甘油和游离脂肪酸对其的激活作用。

Protein kinase C of a human megakaryoblastic leukemic cell line (MEG-01). Analysis of subspecies and activation by diacylglycerol and free fatty acids.

作者信息

Kitagawa Y, Matsuo Y, Minowada J, Nishizuka Y

机构信息

Department of Biochemistry, Kobe University School of Medicine, Japan.

出版信息

FEBS Lett. 1991 Aug 19;288(1-2):37-40. doi: 10.1016/0014-5793(91)80998-i.

DOI:10.1016/0014-5793(91)80998-i

PMID:1908797

Abstract

Protein kinase C (PKC) from a human megakaryoblastic leukemic cell line (MEG-01) was resolved into two fractions by hydroxyapatite column chromatography, which are indistinguishable from the brain type II (beta I/beta II) and type III (alpha) subspecies, by biochemical and immunoblot analysis. In the presence of both phosphatidylserine and diacylglycerol, several free unsaturated fatty acids (FFA's), such as arachidonic, oleic, linoleic and linolenic acids, further enhanced the enzyme activation, and allowed the enzyme to exhibit almost full activity at nearly basal levels of Ca2+ concentration. The concentration of unsaturated FFA's giving rise to the maximum enzyme activation was around 2 x 10(-5) M. Palmitic and stearic acids were inactive. The result implies that, in addition to diacylglycerol, the receptor-mediated release of unsaturated FFA's from membrane phospholipids may also take part in the activation of PKC.

摘要

通过羟基磷灰石柱色谱法，从人巨核母细胞白血病细胞系（MEG-01）中分离出的蛋白激酶C（PKC）可分为两个组分，经生化和免疫印迹分析，这两个组分与脑II型（βI/βII）和III型（α）亚型无法区分。在磷脂酰丝氨酸和二酰基甘油同时存在的情况下，几种游离不饱和脂肪酸（FFA），如花生四烯酸、油酸、亚油酸和亚麻酸，可进一步增强酶的活性，并使该酶在几乎基础水平的Ca2+浓度下表现出几乎完全的活性。产生最大酶活性的不饱和FFA浓度约为2×10（-5）M。棕榈酸和硬脂酸无活性。该结果表明，除二酰基甘油外，受体介导的膜磷脂中不饱和FFA的释放也可能参与PKC的激活。