Meeting Abstract
The distinct chromosomes that regulate sex determination, either X and Y, or Z and W, have been observed to evolve independently in different taxa and rapidly. These sex chromosomes may often contribute specifically to the development of traits unique to each sex; for example, W chromosomes, which are specific to females, are predicted to accumulate mutations that promote female-specific fitness. The observed possibility of rapid turnover in terrestrial isopod sex chromosomes presents an ideal model system for the study of sex chromosome contributions. Genomic analysis of the sex chromosomes (Z and W) in the terrestrial isopod Trachelipus rathkei may provide the opportunity to better understand the rate at which evolution takes place in sex chromosomes, along with generating data that could be used to quantify the influence of sex chromosomes on sexual dimorphism. To examine the role of the Z and W chromosomes in the development of sex-specific traits, we will compare ZZ male isopods with sex-reversed ZW male isopods. These isopods, which have female genotypes but male phenotypes, were generated by implanting androgenic glands from mature males into juvenile female isopods. When these animals reach adulthood, we will measure several morphological traits and examine patterns of gene expression to test how sex chromosomes contribute to sexual dimorphism.
