MUTANT SCREENS FOR DEVELOPMENTALLY INTERACTING GENES

了解胚胎发育在很大程度上取决于学习如何 细胞掌握自己的命运。癌症可导致细胞呈现多个方面 两种不同的命运，因此，学习细胞的机制 命运的指定可能会导致这种毁灭性疾病的治疗。 在模型遗传有机体中筛选抑制或 增强一种已知突变的表型显著增强 我们对有趣的基因网络如何影响细胞命运的理解； 这样的筛选还没有在脊椎动物身上进行过。这 应用程序建议使用现有的遗传有机体模型，即 线虫秀丽线虫设计增强子/抑制子 然后可以应用于一种新的脊椎动物遗传有机体的筛选， 斑马鱼，达尼奥·雷里奥。斑马鱼浮头突变 导致脊索细胞呈现两种不同的细胞命运。 PIE-1突变对特定的线虫有类似的影响 爆裂剂，P2。在这两种情况下，受影响的细胞都保持了正常的早期 信号能力，但随后分化为完全不同的 单元类型。线虫MoM-2突变是部分穿透性的， MoM-2基因可能编码P2信号。携带MoM-2突变的蠕虫 将被诱变并筛选新的突变以增强或 抑制MoM-2的表型。拟议的实验将提供 对线虫细胞命运指定的新见解以及 提供设计和评估此类屏幕的经验，作为前奏 为斑马鱼过程中相互作用的基因设计类似的屏幕 发展。

Understanding embryonic development depends critically on learning how cells acquire their fates. Cancers can cause cells to take on aspects of two different fates, thus, learning the mechanisms underlying cell fate specification may lead to therapies for this devastating disease. Screens in model genetic organisms for mutations that suppress or enhance the phenotype of a known mutation have significantly augmented our understanding of how interesting gene networks affect cell fate; such screens have not yet been undertaken in vertebrates. This application proposes to use an existing model genetic organism, the nematode worm, Caenorhabditis elegans to design enhancer/suppressor screens that can then be applied to a new vertebrate genetic organism, the zebrafish, Danio rerio. The zebrafish floating head mutation causes notochord cells to take on aspects of two different cell fates. The pie-1 mutation has a similar effect on a specific C elegans blastomer, P2. In both cases, the affected cells retain a normal early signaling ability but then differentiate into a completely different cell type. The C elegans mom-2 mutation is partially penetrant and the mom-2 gene may encode the P2 signal. Worms carrying the mom-2 mutation will be mutagenized and screened for new mutations that enhance or suppress the mom-2 phenotype. The proposed experiments will provide new insights into cell fate specification in C. Elegans as well as providing experience designing and assessing such screens, as a prelude to sesigning similar screens for genes interacting during zebrafish development.