“Role of calmodulin in activation of the swim central pattern generator in the leech”
Kevin Crisp, Ph.D., St. Olaf College, Northfield, MN 55057

Leech swimming is generated by a central pattern generator that becomes activated in the presence of serotonin (5-HT).  5-HT appears to activate swimming by stimulating adenylate cyclase (AC), and pharmacological manipulations that elevate cAMP promote swimming.  But AC activity in the leech CNS is also calmodulin-sensitive, suggesting that calmodulin-signaling may regulate the sensitivity of the swim motor circuit to 5-HT.  The first part of this proposal will test the hypothesis that 5-HT directly elevates cAMP by stimulating AC.  This will be done by applying selective agonists of AC-coupled 5-HT receptors to isolated nerve cords, in the presence and absence of AC inhibitors.  The student will use electrophysiological recording techniques to quantify the expression of fictive swimming.  The second part of this proposal will test the effect of calmodulin inhibitors on the promotion of swimming by 5-HT, using similar methods.

Kevin Crisp, Ph.D.
Assistant Professor of Biology
St. Olaf College
1520 St. Olaf Avenue
Northfield, MN 55057

Phone: 507-646-3981
Fax: 507-646-3968

crisp@stolaf.edu