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. ***
