Meeting Abstract

P2.89  Saturday, Jan. 5  An Analysis of the Notch Regulatory Gene fringe in Metamorphic Appendage Patterning of the Red Four Beetle Tribolium castaneum O’BRIEN, DM*; SMITH, FW; JOCKUSCH, EL; University of Connecticut; University of Connecticut; University of Connecticut devin.m.obrien@gmail.com

Modifications of jointed appendages, a defining characteristic of arthropods, have been a major source of diversity and disparity in contemporary insects. In both Drosophila and Tribolium, the Notch pathway has been identified as the primary developmental mechanism responsible for joint formation. Notch, Serrate and Delta, the primary components of this pathway, are conserved in holometabolous insects. However, the main regulatory component of this pathway, fringe (fng), has yet to be investigated beyond Drosophila. Here, we use RNA interference in Tribolium castaneum to analyze the role of fng in joint formation. In Drosophila, fng functions as a suppressor of the Notch pathway, regulating the concentration of the Notch ligands Serrate and Delta. By suppressing the Notch pathway in specific locations, fng promotes both proper joint identity and proper location of joint formation. In Drosophila, downregulation of fng results in ectopic joints, as well as reduction and loss of joints. Congruent with the Drosophila phenotypes, preliminary results from Tribolium show that knockdown of fng can lead to formation of extra joints in the antenna.