A novel protein geranylgeranyltransferase-I inhibitor with high potency, selectivity, and cellular activity
A novel protein geranylgeranyltransferase-I inhibitor with high potency, selectivity, and cellular activity
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DOI：
10.1074/jbc.m600168200
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发表时间：
2006-05-05
影响因子：
4.8
通讯作者：
Casey, PJ
中科院分区：
文献类型：
--
作者：
Peterson, YK;Kelly, P;Casey, PJ
抑制蛋白质前酰化是一种有吸引力的方法来调节由多种信号蛋白控制的细胞过程，包括致癌蛋白，如Ras和Rho GTPases。最大的一类戊烯基化蛋白在其羧基端包含一个所谓的CaaX基序，并受到由蛋白质法酰转移酶（FTase）或蛋白质香叶酰转移酶I型（GGTase-I）附着异戊二烯类脂质的成熟过程的影响。在过去的十年中，fti酶抑制剂（简称FTIs）一直是研究的重点，并在临床试验中显示出疗效。尽管GGTase-I抑制剂（GGTIs）受到的关注较少，但越来越多的证据表明，GGTIs可能会增加使用fti的治疗，并可能对治疗无数其他疾病状态有用。在这里，我们描述了一种选择性的、高效的、细胞活性的GGTase-I抑制剂GGTI-DU40的特性。动力学分析表明，GGTI-DU40的抑制作用对蛋白质底物具有竞争性，对类异戊二烯底物无竞争性；抑制K-i为0.8 nM。GGTI-DU40在体外和活细胞中都对GGTase-I具有高度选择性。研究表明GGTI-DU40阻断了许多香叶酰化CaaX蛋白的烯酰化。用GGTI-DU40治疗MDAMB-231乳腺癌细胞，通过抑制Rho蛋白的过程抑制凝血酶诱导的细胞圆缩，而不显著影响钙通过G β - γ的平行动员。这些研究确立了GGTI-DU40作为询问与蛋白质香叶酰化相关的生物学的主要工具，并为这类新兴的实验疗法定义了一种新的结构。
Inhibiting protein prenylation is an attractive means to modulate cellular processes controlled by a variety of signaling proteins, including oncogenic proteins such as Ras and Rho GTPases. The largest class of prenylated proteins contain a so-called CaaX motif at their carboxyl termini and are subject to a maturation process initiated by the attachment of an isoprenoid lipid by either protein farnesyltransferase ( FTase) or protein geranylgeranyltransferase type I ( GGTase-I). Inhibitors of FTase, termed FTIs, have been the subject of intensive development in the past decade and have shown efficacy in clinical trials. Although GGTase-I inhibitors (GGTIs) have received less attention, accumulating evidence suggests GGTIs may augment therapies using FTIs and could be useful to treat a myriad of additional disease states. Here we describe the characterization of a selective, highly potent, and cell-active GGTase-I inhibitor, GGTI-DU40. Kinetic analysis revealed that inhibition by GGTI-DU40 is competitive with the protein substrate and uncompetitive with the isoprenoid substrate; the K-i for the inhibition is 0.8 nM. GGTI-DU40 is highly selective for GGTase-I both in vitro and in living cells. Studies indicate GGTI-DU40 blocks prenylation of a number of geranylgeranylated CaaX proteins. Treatment of MDAMB-231 breast cancer cells with GGTI-DU40 inhibited thrombin-induced cell rounding via a process that involves inhibition of Rho proteins without significantly effecting parallel mobilization of calcium via G beta gamma. These studies establish GGTI-DU40 as a prime tool for interrogating biologies associated with protein geranylgeranylation and define a novel structure for this emerging class of experimental therapeutics.