Genes code for proteins, but most do not do so at a constant rate under all conditions. These differences in the expression of genes are thought to underlie much of the diversity of organisms. This project uses the lac operon of E. coli, which is responsible for metabolizing lactose, to examine the forces affecting the evolution genetic regulation. Using E. coli collected from high and low lactose environments, the investigators will determine the differences in expression of the lac operon associated with these environmental differences. DNA sequencing of the operon will elucidate the genetic basis of these adaptive differences. The researchers will use recombinant DNA techniques to manipulate the regulation of the genes and then measure the fitness of manipulated strains in the laboratory.
Studies of the lac operon have played a major role in understanding how genetic regulation occurs. This study will use the system to understand the evolution of genetic regulation, a major cause of biodiversity. Changes in genetic regulation are likely play a major part in the evolution of pathogenic bacteria and bacteria which function in basic ecological processes like decomposition. The basic knowledge gained in these studies will help our future understanding of these economic and social impacts of biodiversity.
