Abstracts - Deutsche Zoologische Gesellschaft

202 Physiology PostersP PH.32 - ENThe role of juvenile hormone and allatoregulating neuropeptides in castedifferentiation of the termite Mastotermes darwiniensisFranziska Wende 1 , Martina Meyering-Vos 1 , Klaus H. Hoffmann 1 , Manfred Kaib 21Department of Animal Ecology I, University of Bayreuth; 2 Department of Animal Physiology,University of BayreuthCaste differentiation in social insects is not well understood, but juvenile hormones (JH) are assumedto play a major role. Although some results are available on JH titres in different castes of termites,no such studies have been done on the most primitive termite Mastotermes darwiniensis. This speciesis of special interest as in contrast to other lower termites it has been suggested to follow a bifurcatedontogenetic pathway similar to the higher termites. In such pathways, the split between sterile andreproductive line occurs in an early larval stage. Allatostatins of the FGL-amide family (AS-A) inhibitJH biosynthesis in the corpora allata. Therefore, they may indirectly control caste differentiation. Theprecursor of M. darwiniensis AS-A has been partially identified encoding at least 14 putative peptides.In order to understand the role of JH and ASs in caste differentiation, we measured JH titres in thehaemolymph by HPLC-MS and, in parallel, we quantified the AS-A gene expression in various castesand developmental stages. Preliminary results reveal high JH titres combined with low gene expressionof the AS-A gene in intermediate larval stages compared to other larval stages and sterile workers.The high JH titre suggests that in Mastotermes the point of bifurcation may not occur in early but inintermediate stages. The expression pattern of the AS-A gene correlates with the JH titre indicating anallatostatic role of these neuropeptides. Supported by DFG (GRK 678/2).