K99 to R00 Transition-Neural Crest Migration and Survival in Zebrafish

该应用程序的目的是使用斑马鱼作为|模型来解剖foxd3介导的神经嵴（NC）细胞存活和迁移终点的分子成分，以确定这些途径是否促进体内ng源性肿瘤的转移。斑马鱼具有与人类基因组密切的同源性，以及其保守的调节组织和器官发育的分子途径，为开展此类研究提供了强有力的工具。我们之前鉴定并鉴定了一个斑马鱼foxd3突变系，该突变系具有特定的NC细胞存活和迁移缺陷。我们还发现Snai1b转录因子是Foxd3功能的关键中介。这项应用的潜在假设是，对Foxd3通路的了解将提供对nc源性肿瘤转移的环境要求的理解。在Aim 1中，遗传上位性和生物化学将决定Foxd3是否直接激活snai1b的表达。该目的还将确定Snai 1b是否通过抑制一个或多个BH3-only基因的表达来抑制NC凋亡，并通过抑制cadherin-6的表达来促进NC迁移。在Aim 2中，将分析在bK99期通过微阵列筛选鉴定出的一系列基因的NC表达模式和敲低表型，以及它们的能力

The goal oflhis application is to use the zebrafish as a |nodel to dissect the molecular connponents of Foxd3-mediated neural crest (NC) cell survival and migration end to determine if these pathways promote metastasis in NG-derived tumors in vivo. The zebrafish with its close synteny to the human genome and its conserved molecular pathways regulating the development of tissues and organs, Offers a powerful tool with which to conduct such research. We previoulsy identified and characterized a zebrafish foxd3 mutant line that has specific NC ceil survival and migration defects. We also identified the Snai1b transcription factor-as a critical mediator of Foxd3 function. The underlying hypothesis of this applicatipn is that knowledge of the Foxd3 pathway wiII provide an understanding environments, requirement for the metaststasis of NC-derived tumors. In Aim 1, genetic epistasis and biochemistry will determine if Foxd3 directly activates snai1b expression. This aim will also will also determine whether Snai 1b inhibits NC apoptosis by repressing the expression of one or more BH3-only genes, and promotes NC migration by repressing cadherin-6 expression . In Aim 2, a list of genes identified in a microarray screen during the bK99 phase will abe analyzed for thier NC expression pattern and knockdown phenotypes, as well as their ability to rescue NC defects in foxd3 mutant and snai 1b MO-injected embryos. In Aim 3, foxd3 and snai1b will be expressed in developing NC cells to examine their potential roles in promoting metastasis in established zebrafish NC tumors, including a new model identified during the K99 phase. Rodney Stewart will continue to receive advanced training in genetics, neurobiology and oncology throughout his career. This research proposal is designed to support the candidate as an independent investigator during the first 3 years of a faculty appointment in the Department of Oncology Sciences at the Huntsman Cancer Institute at the University of Utah. Huntsrnan Cancer Institute at the yniyersity of-Utahnd