Professor Emeritus of Biology
Research Topic:Genetic analysis of reproductive behavior and cardiac rhythms
My research area is the genetics of behavior, using Drosophila as the experimental organism. I am currently using genetics and pharmacology to investigate two separate phenomena, cardiac rhythms and female receptivity.
Cardiac rhythms of Drosophila originate in a myogenic pacemaker. My collaborator, Dr. Harold Dowse (this Department) and I have identified two ion channels central to this pacemaker: A voltage-gated “OPQ-Type” Calcium channel, and a fast Calcium-gated potassium channel encoded by the slowpoke gene. Other Potassium channels may be involved, but sodium channels do not play a role in heartbeat. We have found several mutants with severe cardiac arrhythmias: slowpoke, no-action-potential, amnesiac, Dopa decarboxylase, and ether-a-go-go. We have also found that serotonin, octopamine, norepinephrine, dopamine, and acetylcholine are cardioacceleratory, while a pentapeptide from Limulus slows heartbeat.
Female sexual receptivity:
Receptivity is switched on in young adults. I am studying the genetic and endocrine program underlying the switch-on, using a combination of genetic, physiological, and ethological approaches. A few genes are known to be crucial to receptivity; I am utilizing two, apterous (ap) and icebox. apterous mutants are deficient in JH, and therefore develop receptivity very slowly. icebox, discovered to be a behavioral mutation in this lab, exerts a stronger effect on receptivity than any other known gene. I also use JH analogs and JH inhibitors in these studies. I characterize the “microresponses” of females—the frequency and details of their signals to sexually active males—by analyzing videotaped behavior.