ABI-1 GENE PRODUCT IN SIGNAL TRANSDUCTION & TRANSFORMATION BY VABL & BCR-ABL

这项研究描述了确定阿比-L功能的实验 (Abelson InterActor-1)蛋白在致癌转化中的作用 Abelson癌蛋白v-Abl和bcr-abl。Abelson基因编码一种 胞质酪氨酸激酶；v-Abl是一种由 Abelson鼠白血病病毒，导致小鼠前B淋巴瘤，这是 Bcr-abl是慢性髓细胞性疾病的一个较弱的版本 白血病(CML)，有时还包括急性淋巴细胞白血病(ALL) 人类。ABI-L最初是通过酵母双杂交鉴定出来的 系统作为一种新的SH3蛋白与富含Pro的C末端结合 并抑制v-Abl的转化活性。遗传和 将进行生化实验以确定哪种信号 转导通路受Abi-1蛋白的控制或抑制 或被Abi-1蛋白抑制。高水平表达的细胞系 将检查野生型或突变型Abi-1的激活情况 下游靶基因(c-myc、dhfr)；激活下游 靶基因(c-myc、dhfr)：激活已知的PDGF途径(RAS、 PLCg、PI3K)；刺激细胞周期调节蛋白；以及 Jak/Stat和Crk1蛋白的磷酸化和激活。人类 CML患者的肿瘤样本将进行检测，以确定其水平 ABI-1蛋白和与bcr-abl结合的部分。最后，v-的突变体 ABL将生成该转换活动。酵母双杂交 系统将用于分离与一个伴侣结合但不结合的突变体 而携带相关突变的病毒将会被 在细胞系和小鼠中测试转化活性。这些 实验应该有助于识别各种途径中的哪一条 是致癌转化所必需的。这些 实验可能会提供关于诱导和 人类慢性粒细胞白血病和急性淋巴细胞白血病的疾病进展。

This study describes experiments to determine the functions of the Abi-l (Abelson interactor-1) protein in oncogenic transformation by the Abelson oncoproteins v-Abl and BCR-ABL. The Abelson gene encodes a cytoplasmic tyrosine kinase; v-Abl is an activated form expressed by the Abelson murine leukemia virus, causing a pre-B lymphoma in mice, which BCR-ABL is a less potent version responsible for chronic myelogenous leukemia (CML) and, sometimes, acute lymphocytic leukemia (ALL) in humans. Abi-l was originally identified using the yeast two-hybrid system as a novel SH3 protein that binds to the proline-rich C terminal tail of v-Abl and suppresses its transforming activity. Genetic and biochemical experiments will be performed to determine which signal transduction pathways are controlled or inhibited by the Abi-1 protein or inhibited by the Abi-1 proteins. Cell lines expressing high levels of either the wild-type or mutant Abi-1 will be examined for activation of downstream target genes (c-myc, DHFR); for activation of downstream target genes (c-myc, DHFR): for activation of known PDGF pathways (Ras, PLCg, PI3K); for stimulation of cell cycle regulatory proteins; and for phosphorylation and activation of Jak/Stat and Crkl proteins. Human tumor samples from CML patients will be tested to determine the level of Abi-1 protein, and the fraction bound to BCR-ABL. Finally, mutants of v- Abl will be generated that transforming activity. The yeast two-hybrid system will be used to isolate mutants that bind to one partner but not to others, and viruses carrying the relevant mutations will then be tested for transforming activity in cell lines and mice. These experiments should help identify which of the various pathways emanating from the Abl kinase are required for oncogenic transformation. These experiments may provide important information about the induction and progression of disease in human CML and ALL.