Genomic technology makes it possible to understand the role of many different genes in the process of species formation. By taking advantage of genome-wide research programs on model organisms, the investigators can conduct targeted studies on additional species, thereby discovering the genetic footprints of key evolutionary processes. They will use emerging genomic data on sea urchins to elucidate patterns and processes of molecular evolution acting during rapid species formation. They will target genes involved in reproductive success by 1) sequencing cDNA libraries from testes of the tropic urchin Echinometra oblonga, and comparing to the related species Strongylocentrotus purpuratus; 2) comparing proteins from the morphologically divergent sperm of two E. oblonga sub-species: and 3) screen a genomic library from S. purpuratus to find and sequence the chromosomal region surrounding the bindin gene, known to be central to reproductive isolation.
The power of genomics is the discovery of many genes. The power of the comparative method is the elucidation of gene function and evolution through well-chosen examples of divergent species. This study applies both approaches to understanding the genes involved in reproductive success in a system in which fertilization is extremely well understood. The combination of classic knowledge about sea urchin fertilization, powerful new evolutionary models, and the burgeoning of genomics will provide rapid advances in functional and evolutionary biology.