Research Interests

My interests involve the molecular evolution of genes and genomes, and how these can be utilized to determine phylogenetic relationships among organisms. Previous studies have investigated the nature of the progenitor to chloroplasts in plants and algae. By analysis of gene sequences in bacteria, algae, and plants I was able to show that multiple endosymbiotic events have occurred giving rise to the present day diversity among chloroplast types, and that gene transfer among organelles (chloroplast, mitochondria, and the nucleus) has taken place.

More recently, I have studied the evolution of the plastid genome in a parasitic nonphotosynthetic plant to determine what effect lack of photosynthesis has had on the gene content and rate of evolution in plastid DNA. Collaborators and I have found that all of the genes encoding bioenergetic proteins (for photosynthesis and chlororespiration), RNA polymerase, and many genetic proteins are absent or are pseudogenes in the parasite, and the genome is less than one-half the size of chloroplast DNA in related, photosynthetic species. However, from analysis of genes that are remaining, northern blot analysis, and reverse PCR it is evident that the genome is still functional and required for processes other than bioenergetics.

Future research will be focused on the phylogenetic relationships among various plant and algal lineages, evolution of mitochondrial and chloroplast DNA, and diversity among populations of native Hawaiian species.