Meeting Abstract

129.2  Tuesday, Jan. 7 13:45  Interactions of major royal jelly proteins and juvenile hormone on growth and development of Madagascar hissing cockroaches (Gromphadorhina portentosa) DAVIS, J.E.*; CALE, K.M.; NICHOLAS, S.A.; Radford University; Radford University; Radford University jdavis319@radford.edu

Until recently, it was thought that the major royal jelly proteins (MJRP) present in royal jelly were relatively unique to hymenopteran insects, acting in such species to catalyze the development of queen morphotypes. However, recent studies by Kamakura (2011) and others have suggested that MRJP do in fact have a strong effect on non-hymenopteran insects. Here we present the results of recent studies in our laboratory exploring the effects of MRJP supplementation on growth rate, size, morphology and fecundity in the Madagascar hissing cockroach (Gromphadorhina portentosa). Protein gel assays revealed that 30 day heat treatment of royal jelly denatures large MRJP. Based on this finding we supplemented the diet of nymphal cockroach colonies with fresh or heat-denatured royal jelly. We found significant increases in growth rate, overall adult size, and fecundity in cockroaches reared with fresh, but not denatured, royal jelly supplementation. To further elucidate the mechanisms through which MRJ proteins may modify growth, we conducted additional studies in which colonies were given royal jelly in concert with methoprene, a juvenile hormone agonist. Methoprene treatment alone produced juviform adults of near normal size, while treatment with methoprene and royal jelly produced adults of dramatically larger size and greater sexual dimorphism than both control groups and groups exposed to royal jelly alone. However, adults resulting from the combined royal jelly and methoprene treatment have thus far failed to reproduce. Findings from these studies demonstrate that the effects of exogenous MRJP are not limited to hymenopterans or even to the broader endopterygotid superorder.