This fall, two graduate students in the Wilson lab have defended their thesis projects and graduated with an M.Sc. Degree. The most recent, Lana Shaya, defended her thesis today. Both students are focused on cytochrome P450 enzymes but their approaches, techniques, and species of interest are quite different.

Lana’s research has focused on two important model fish species, zebrafish and medaka. Both are small fish used in toxicology studies. They have similar and important advantages as model fish species: a short generation time, asynchronous and continuous breeding, large clutch sizes, clear embryos that allow direct observation of their development, short development, and a completed genome. Lana has studied the expression of cytochrome P450 family 3 (CYP3) genes in both species. The CYP3 genes in fish are diverse. Compared to mammals, there are many novel genes and the function of these genes is not known. CYP3 genes in mammals are very important for drug and contaminant metabolism and we presume they have a similar function in fish. Lana examined the expression of multiple CYP3 genes from a variety of organs in each species. Most interestingly, her research highlights relatively high expression of some of these genes in olfactory rosettes, an organ in the fish nose that is important for odorant sensing. Her work also clearly shows significant differences in expression patterns of CYP3 genes between males and females.

Contrary to Lana, whose research is at the bench doing molecular biology, Chris’ uses computers to do all of his research. Chris used bioinformatics tools to examine the CYP genes in the polychaete worm, Capitella telata. Chris annotated all of the CYP genes in the genome of this species and in the process has found 24 novel CYP families. Chris completed phylogenetic analyses of the Capitella CYP genes to aid in naming the genes and to understand their evolution. Capitella telata is a very interesting species for the study of CYP genes. First, these worms are found in high density in highly contaminated marine sediments including areas impacted by oil spills. Research has shown that they can metabolize polycyclic aromatic hydrocarbons (PAHs), common contaminants from oil and combustion processes. This function is typically mediated by CYPs in other species. Indeed, studies have shown two CYP genes with elevated expression with PAH exposure. Second, these worms produce the steroid hormone estradiol. CYP genes are very important for the production of steroid hormones, including estradiol, in vertebrates. Chris’ research has raised some important functional hypotheses for the CYPs found in the worm genome.