Drosophila Ptc has been shown to be a receptor for the Hedgehog morphogen and to interact with the membrane protein Smoothened. In C. elegans, two predicted ptc gene homologues have been identified by the C. elegans Whole Genome Sequencing Consortium. In addition, characterisation of a cDNA sequence has led to the identification of a third member, ptc-3. C. elegans is the first organism for which more than a single ptc gene has been identified. PTC-1 and to other PTC proteins.
Mutant screens are in progress.