Helps N R, Vergidou C, Gaskell T, Cohen P T
Department of Biochemistry, University of Dundee, UK.
FEBS Lett. 1998 Oct 30;438(1-2):131-6. doi: 10.1016/s0014-5793(98)01286-1.
A novel Drosophila melanogaster protein, termed inhibitor-t, that bears 41% sequence similarity to human protein phosphatase inhibitor-2 has been identified using human protein phosphatase 1 (PP1) in the yeast two hybrid system. Inhibitor-t mRNA is detected in adult males, larvae and pupae and the 184 amino acid thermostable protein located only in testis. The gene for inhibitor-t maps to cytological location 86F1 on the third chromosome. Bacterially expressed inhibitor-t specifically inhibits both mammalian and D. melanogaster PP1 catalytic subunits with an IC50 of approximately 200 nM. A motif -FEX1X2RK-, conserved between inhibitor-t, inhibitor-2 and its Saccharomyces cerevisiae homologue Glc8, is demonstrated to be required for binding to PP1.
利用酵母双杂交系统中的人蛋白磷酸酶1（PP1），已鉴定出一种名为抑制剂 - t的新型黑腹果蝇蛋白，它与人类蛋白磷酸酶抑制剂 - 2具有41%的序列相似性。在成年雄性、幼虫和蛹中检测到抑制剂 - t mRNA，而这种184个氨基酸的热稳定蛋白仅位于睾丸中。抑制剂 - t基因定位于第三条染色体的细胞学位置86F1。细菌表达的抑制剂 - t能特异性抑制哺乳动物和黑腹果蝇的PP1催化亚基，IC50约为200 nM。已证明抑制剂 - t、抑制剂 - 2及其酿酒酵母同源物Glc8之间保守的基序 -FEX1X2RK- 是与PP1结合所必需的。
