Project Summary

We will analyze the functions of otk and CG8964 in planar cell polarity in Drosophila. Otk and CG8964 are the homologs of the vertebrate planar cell polarity gene PTK7. We speculate that these two genes operate in a redundant manner and have therefore escaped their detection as planar polarity genes in the genetic screens performed so far. If that turns out to be true, the analysis of their function in Drosophila will provide a great opportunity to pursue genetic and imaging experiments that cannot be performed in frogs or mice due to technical limitations in these vertebrate systems.

We will first continue with the generation of the CG8964 single knock-out and the otk, CG8964 double knock-out animals. As soon as we have these mutant lines, we will perform phenotypic analyses with re-spect to planar polarity phenotypes in the wings and eyes and with respect to defects in wingless signaling in the embryo and imaginal disc tissues. We will continue with the analysis of the subcellular localization of both proteins in different tissues, in particular those that are planar polarized, e. g. the wing imaginal disc. Antibodies are currently being generated. We will furthermore generate transgenic lines with GFP fusion versions of both proteins to perform rescue experiments and overexpression experiments. Depending on the outcome of these experiments, we will investigate genetic interactions with other known PCP genes to place otk and CG8964 into this functional network. In addition, we will perform structure-function analyses of both genes and will search for protein interaction partners both in a candidate approach and in an unbi-ased manner using co-IP, followed by mass spectrometry.