PROBING DROSOPHILA ABELSON TYROSINE KINASE WITH GENETICS

这项研究将使用遗传分析来识别和分子 表征受影响的信号转导途径上的蛋白质 Abelson酪氨酸激酶（Abl）。 活化Abl激酶 是一种人类致癌基因，导致慢性粒细胞白血病和 急性淋巴细胞白血病 As酪氨酸激酶信号转导 昆虫和哺乳动物之间的通路通常是保守的， 在果蝇模型中获得的Abl激酶信号转导通路 系统可能会导致这些人类白血病的新的治疗模式。 Abl纯合突变体的蝇发育至化蛹。 新 增强或恶化这种表型的突变，导致前蛹 致命性，已经恢复。 换句话说， 增强子突变杂合突变体和增强子突变的纯合突变体 在化蛹前死亡。 因此，这些新的增强子突变在 在功能上与Abl激酶冗余的基因。 两个这样 新的增强子突变（M89和M109）将被映射到一个精确的 染色体定位和cDNA将被回收、克隆和测序。 这些基因的表达模式将被表征。 新的突变 将产生这些基因的等位基因，并将产生突变表型。 表征了 克隆的cDNA将被重新引入转基因果蝇 并且突变表型的拯救将被测试作为确认， 正确的cDNA已经克隆出来了 还提出了一种新的遗传筛选方法。 在遗传背景下， 次优Abl酪氨酸激酶活性，将恢复新的突变 以激酶依赖的方式改变这种背景。 因为这些 突变的影响取决于Abl激酶活性，它们将 可能存在于编码蛋白质的基因中， 与Abl的激酶活性相关的酶，如直接底物、激酶 调节剂或特异性磷酸酶。 这些突变将被映射到 一个精确的染色体定位，cDNA回收，克隆和测序。 这些基因的表达模式将被表征。 的cdna 将克隆的基因重新引入转基因果蝇中， 将测试表型以确认正确的cDNA已被表达。 克隆的。

This research will use genetic analysis to identify and molecularly characterize proteins that are on signal transduction pathways influenced by the Abelson tyrosine kinase (Abl) in Drosophila. Activated Abl kinase is a human oncogene, resulting in both chronic myelogenous leukemia and acute lymphocytic leukemia. As tyrosine kinase signal transduction pathways are often conserved between insects and mammals, insights into Abl kinase signal transduction pathways gained in the Drosophila model system may result in new modes of treatment for these human leukemias. Flies which are homozygous mutant for Abl develop to pupation. New mutations which enhance, or worsen this phenotype, resulting in pre-pupal lethality, have been recovered. In other words animals which are heterozygous mutant for an enhancer mutation and homozygous mutant for Abl die before pupation. As such these new enhancer mutations are in genes which are functionally redundant to the Abl kinase. Two of these new enhancer mutations (M89 and M109) will be mapped to an exact chromosomal location, and cDNAs will be recovered, cloned and sequenced. The expression patterns of these genes will be characterized. New mutant alleles of these genes will be generated and mutant phenotypes will be characterized. cDNAs cloned will be re-introduced into transgenic flies and the rescue of mutant phenotypes will be tested as confirmation that the correct cDNAs have been cloned. A novel genetic screen is also proposed. In a genetic background with sub-optimal Abl tyrosine kinase activity, new mutations will be recovered that alter this background in a kinase-dependent manner. As these mutations depend on Abl kinase activity for their effects, they will likely be in genes which code for proteins which are biochemically associated with Abl's kinase activity, such as direct substrates, kinase regulators or specific phosphatases. These mutations will be mapped to an exact chromosomal location, and cDNAs recovered, cloned and sequenced. The expression patterns of these genes will be characterized. cDNAs cloned will be re-introduced into transgenic flies and rescue of mutant phenotypes will be tested to confirm that the correct cDNAs have been cloned.