Cell division, apoptosis during zebrafish hepatogenesis

描述(由申请人提供)： 了解细胞分裂和细胞死亡在斑马鱼肝脏发生中的作用是本研究的目的。这将是通过霍普金斯实验室即将完成的插入突变筛选产生的斑马鱼突变的系统筛选的首批努力之一。这项筛查已经确定了500多个基因，当这些基因发生突变时，会扰乱早期发育。这些基因中的很大一部分已被鉴定为在细胞分裂或凋亡中发挥作用，或者是新基因。这些突变将为发现在肝脏发生过程中调节细胞生命和死亡之间的平衡的基因以及为新的、必要的基因分配功能提供肥沃的土壤。我的第一个目标是提供斑马鱼肝脏发育的详细描述，包括描绘肝脏发生过程中细胞分裂和死亡的模式。其次，我将全面描述Pescadillo(PER)突变体的特征，在其他缺陷中，它只发育出一个基本的肝脏，我将测试PES中的肝原性衰竭是由于PES肝细胞无法分裂所致的假设。第三，我将通过研究肝脏的大小和这些突变体在发育过程中肝脏特异性基因的表达模式，询问霍普金斯筛查发现的参与细胞分裂或凋亡的基因中是否有任何基因对肝脏发生有贡献。最后，我将对所有新的基因突变进行筛选，以确定那些肝脏大小缺陷的基因。已确定的突变将受到进一步的分析，包括对突变的描述，基因在野生型发育过程中的表达模式，以及对肝脏发生的全面调查，以便开始了解其中一些新的、必要的基因的功能。

DESCRIPTION (provided by applicant): Understanding the contributions of cell division and cell death to zebrafish hepatogenesis is the aim of this study. It will be among the first efforts to systematically screen through the zebrafish mutants generated by an insertional mutagenesis screen that is near completion in the Hopkins laboratory. This screen has identified over 500 genes which, when mutated, disrupts early development. A significant portion of these genes have been identified as having a role in either cell division or apoptosis or are novel gene. These mutants will provide fertile ground for both uncovering genes that regulate the balance between cellular life and death during hepatogenesis as well as assigning a function to novel, essential genes. My first aim is to provide a detailed description of zebrafish liver development, including delineation of the pattern of cell division and death during hepatogenesis. Second, I will fully characterize the pescadillo (per) mutant which, among other defects, only develops only a rudimentary liver and I will test the hypothesis that hepatogenic failure in pes results from an inability for pes hepatocytes to divide. Third, I will ask whether any of the genes involved in cell division or in apoptosis uncovered by the Hopkins screen contribute to hepatogenesis by investigating the size of the liver and the pattern of liver-specific gene expression during development in these mutants. Finally, I will screen through all of the novel gene mutants to identify those with a defect in liver size. The mutants identified will be subject to further analysis including a description of the mutant, the expression pattern of the gene during wild-type development and a full investigation hepatogenesis so that the function of some of these novel, essential genes may begin to be understood.