University of Tennessee at Knoxville
Neuropeptides in Drosophila
Dr. Park was a graduate student in the Hall lab from 1996 to 2000, working alongside Jeff Hall and Michael Rosbash on the topic of biological rhythms in the fruit fly.
Adipokinetic hormones (AKHs) are metabolic neuropeptides, mediating mobilization of energy substrates from the fat body in many insects. The Drosophila AKH (dAkh) gene is expressed exclusively in the neuroendocrine cells in the corpora cardiaca from late embryos to adult stages. Projection patterns emanating from the AKH neurons indicated that AKH has multiple target tissues, including the larval aorta and the adult crop and brain. Studies using transgenic manipulations of the dAkh gene demonstrated that AKH induced both hypertrehalosemia and hyperlipemia. Starved wild-type flies displayed prolonged hyperactivity prior to death. This novel behavioral pattern could be associated with foraging activities in response to starvation. In contrast, flies devoid of AKH neurons not only lacked this type of hyperactivity, but also displayed strong resistance to starvation-induced death, implying a role for AKH in the regulation of starvationinduced foraging behavior.