E. coli Termination Factor Rho, pBR322 Rop, and mRNA Degradation

Gronostajski核因子I （Nuclear Factor I， NFI）是一类在系统发育上保守的位点特异性dna结合蛋白，在包括有机体发育在内的基本细胞过程中发挥重要作用。这些研究检查了含有单个NFI基因的生物体的简单发育系统。利用Tcl靶向诱变产生NFI基因缺失突变体，研究NFI在秀丽隐杆线虫生长发育中的功能。纯合子零突变体和表达特定突变形式NFI的生物体的表型将为了解这一进化保守的dna结合蛋白家族如何在秀丽隐杆线虫和其他生物体中发挥作用提供重要见解。这种缺失突变体的表型将在细胞活力、胚胎和胚胎后发育方面进行分析。如果零等位基因产生早期致死表型，它将被携带在含有野生型基因染色体外阵列的菌株中，这将允许通过阵列的分裂产生纯合缺失动物。这种理解秀丽隐杆线虫发育过程中NFI功能的“反向遗传”方法也将允许测试脊椎动物NFI基因是否可以补充秀丽隐杆线虫基因，从而评估秀丽隐杆线虫突变体在分析涉及脊椎动物发育的其他多基因家族中有多有用。＊＊＊

9612367 Gronostajski Nuclear Factor I (NFI) is one of a class of phylogenetically-conserved site-specific DNA-binding proteins that play an essential role in fundamental cellular processes including organismal development. These studies examine a simple developmental system in a organism containing a single NFI gene. The function of the NFI in the growth and development of C. elegans will be studied by the generation of deletion mutants in the NFI gene using Tcl targeted mutagenesis. The phenotype of homozygous null-mutants, and of organisms expressing specific mutated forms of NFI will yield important insights into how this family of evolutionarily-conserved DNA-binding proteins function in C. elegans and other organisms. The phenotype of this deletion mutant will be analyzed in respect to cell viability, embryonic, and post-embryonic development. If the null-allele generates an early lethal phenotype, it will be carried in a strain containing an extrachromosomal array of the wild-type gene which will allow the generation of homozygous deletion animals by partitioning of the array. This "reverse genetic" approach to understanding NFI function during C. elegans development will also allow testing whether the vertebrate NFI genes can complement the C. elegans gene and thus assess how useful C. elegans mutants may be in the analysis of other multigene families involved in vertebrate development. ***