There are several lines of molecular biology research currently underway in Professor Herrin's laboratory. A major area concerns group I intron ribozymes that are found in certain chloroplast genes. These genetic elements can be viewed as molecular parasites that have invaded genes during evolution. They have two unique properties which promote their existence. One is the ability of the RNAs they encode to catalyze specific reactions with themselves (i.e. they can self-splice). A second feature is that unique DNA restriction endonucleases are often encoded within these introns. These endonucleases, which have unusually large recognition sequences, function in vivo to initiate mobility of the intron into intronless alleles. We are investigating both of these intron-related processes using biochemical and genetic approaches.
A second major theme in the lab concerns circadian (~24 hour) rhythms. Specifically, we are interested in how gene expression is controlled by the circadian clock. These studies are also expected to eventually shed light on the nature of the 24-hour, biological clock.