Our laboratory is interested in understanding the evolution and function of the genes for the mammalian ribosomal RNA. Our study system includes several cultured cell lines of the Chinese hamster (Cricetulus griseus). We are using recombinant DNA technology and cloned genes to identify the mechanisms which are involved in controlling ribosomal RNA gene expression in normal and transformed (cancer-like) cells. This work involves understanding the interactions between RNA, various protein factors and regions of DNA. These investigations are carried out using living cultured cells, as well as in-vitro experiments involving purified components.
Our laboratory is also seeking to understand how the cell maintains its multiple (greater than 200) copies of the large ribosomal RNA gene. We have identified a fragment of the ribosomal RNA gene, termed frDNA which has multiplied within the chromosomes of the Chinese hamster. We expect that examination of these pseudogenes and the processes which produced and maintain them, will provide information on the mechanisms operating within the nucleus which preserve the integrity of copies of multi gene families.
We are also involved in collaborative work using recombinant DNA technology to understand biological responses to environmental pollutants. These efforts examine the expression of cytochrome P450 in fish.