Rodriguez A, Zhou Z, Tang M L, Meller S, Chen J, Bellen H, Kimbrell D A
Department of Biology, University of Houston, Texas 77204, USA.
Genetics. 1996 Jun;143(2):929-40. doi: 10.1093/genetics/143.2.929.
We are using Drosophila as a model system for analysis of immunity and tumor formation and have conducted two types of screens using enhancer detector strains to find genes related to these processes; genes expressed in the immune system (type A; hemocytes, lymph glands and fat body) and genes increased in expression by bacterial infection (type B). For type A, tissue-specific reporter gene activity was determined. For type B, a variation of enhancer detection was devised in which beta-galactosidase is assayed spectrophotometrically with and without bacterial infection. Because of immune system involvement in melanotic tumor formation, a third type was hypothesized to be found among types A and B; genes that, when mutated, have a melanotic tumor phenotype. Enhancer detector strains (2800) were screened for type A, 900 for B, and 11 retained for further analysis. Complementation tests, cytological mapping, P-element mobilization, and determination of lethal phase and mutant phenotype have identified six novel genes, Dorothy, wizard, toto, viking, Thor and dappled, and one previously identified gene, Collagen IV. All are associated with reporter gene expression in at least one immune system tissue. Thor has increased expression upon infection. Mutations of wizard and dappled have a melanotic tumor phenotype.
我们正在使用果蝇作为模型系统来分析免疫和肿瘤形成，并使用增强子检测菌株进行了两种类型的筛选，以寻找与这些过程相关的基因；在免疫系统中表达的基因（A 型；血细胞、淋巴腺和脂肪体）以及因细菌感染而表达增加的基因（B 型）。对于 A 型，测定了组织特异性报告基因活性。对于 B 型，设计了一种增强子检测的变体，其中在有和没有细菌感染的情况下通过分光光度法测定β-半乳糖苷酶。由于免疫系统参与黑色素瘤的形成，推测在 A 型和 B 型中会发现第三种类型；即那些突变后具有黑色素瘤表型的基因。对 2800 个增强子检测菌株进行了 A 型筛选，900 个进行了 B 型筛选，11 个被保留用于进一步分析。互补试验、细胞学定位、P 元素移动以及致死期和突变体表型的测定已经鉴定出六个新基因，分别是 Dorothy、wizard、toto、viking、Thor 和 dappled，以及一个先前已鉴定的基因，胶原蛋白 IV。所有这些基因都与至少一种免疫系统组织中的报告基因表达相关。Thor 在感染后表达增加。wizard 和 dappled 的突变具有黑色素瘤表型。
