NIH program “Tools for genetic and genomic studies in emerging model organisms (PA-04-135)”
Integrating genetic and genomic resources for C.briggsae
Raymond Miller (Washington University School of Medicine, St. Louis) and Bhagwati Gupta (McMaster University, Hamilton, Canada)
The soil-nematode Caenorhabditis briggsae is an emerging model organism for biomedical research. It has diverged roughly 100 million years ago from C. elegans but still shares almost identical morphology. The availability of powerful genetic tools and genome sequences in these two nematodes promise rapid advances in the identification of eukaryotic gene products and signaling pathways thereby facilitating study of the conservation/divergence of gene networks. C. briggsae investigators agree the key required experimental tool for the organism is a good genetic linkage and Single Nucleotide Polymorphism (SNP) map tied to the draft sequence. This is needed to facilitate forward genetics including mapping of C. briggsae mutants as a prelude to positional cloning and understanding gene function. We will provide this tool, constructing a dense genetic map of C. briggsae by genotyping SNPs on two sets of recombinant inbred strains. The map will anchor and orient contigs from the draft sequence, making the sequence more useful. We will assemble collections of mutant animals and by taking genetic approach carefully map the mutations on various chromosomes (high quality linkage map). The two maps (SNP-based map and linkage map) will be tied with each other by high throughput methods using bulked segregants. We will use similar techniques to map many mutants found by investigators in the field, and we will make the data and mutants publicly available. This will be an invaluable resource for comparative study of gene function and regulation between the two leading nematode species.