MN2+ -PHOSPHOLIPID STIM PK AND LEUKEMIC DIFFERENTIATION

这个项目涉及一种新的生物化学和细胞生理学 鉴定的蛋白激酶，称为“PK-P”，用于 磷脂调节蛋白激酶及其主要内源性底物 第73页。 该系统在鼠和人白血病细胞中是可检测的， 其中它可能在多集落刺激因子（IL-3）信号传导中起作用 转导和化学诱导分化。 pp 73已经 纯化，并将进一步表征，关于 已观察到其表现出的蛋白水解活性;其相互作用 与磷脂和二价阳离子，并与蛋白激酶作为 底物;以及通过部分氨基酸测序确定的其结构 和免疫分析。 PK-P也被发现很容易 磷酸化核糖体蛋白S6。 这种反应将进一步 定量并与其他激酶的磷酸化进行比较， 确定对体外翻译的影响。 前体，其他亚单位 或相互作用的活动，或修饰调节PK-P将是 鉴定 PK-P/pp 73系统对化学物质的反应模式 和HL-60人髓系的生物分化诱导剂， 白血病细胞系，以及IL-3对DA-1鼠白血病细胞的治疗 将使用蛋白质的直接测量进一步表征细胞系， 蛋白质磷酸化水平和亚细胞分布 免疫印迹技术。 这些组分与膜的相互作用 还将研究来自经受各种这样的处理的这样的细胞的细胞。 分子生物学研究的目的是克隆的cDNA基因， 将进行PK-P，以便PK-P的完整一级结构可以 最终要确定。

This project deals with the biochemistry and cellular physiology of a newly identified protein kinase, referred to as "PK-P", for phospholipid-modulated protein kinase, and its major endogenous substrate pp73. This system is detectable in murine and human leukemic cells, wherein it may play a role in multi-colony stimulating factor (IL-3) signal transduction and chemically inducible differentiation. pp73 has been purified, and will be characterized further, with respect to the proteolytic activity which it has been observed to exhibit; its interaction with phospholipids and divalent cations, and with protein kinases as a substrate; and its structure as determined by partial amino acid sequencing and immunologic analysis. PK-P has also been found to readily phosphorylate ribosomal protein S6. This reaction will be further quantitated and compared to phosphorylation by other kinases, and its effects upon in vitro translation determined. Precursors, other subunits or interacting activities, or modifications modulating PK-P will be identified. The pattern of response of the PK-P/pp73 system to chemical and biologic differentiation inducing agents of the HL-60 human myeloid leukemic cell line, and to IL-3 treatment of the DA-1 murine leukemic cell line will be further characterized using direct measurement of protein and phosphorylation levels and subcellular distribution by protein immunoblotting techniques. Interaction of these components with membranes from such cells subjected to various such treatments will also be studied. Molecular biologic studies aimed towards the cloning of the cDNA gene for PK-P will be undertaken, so that the complete primary structure of PK-P can ultimately be determined.