The planar cell polarity (PCP) pathway functions to orient cells within the plane of an epithelial tissue. The fruit fly is a great model system for studying the PCP pathway—the bristles on the fly’s back and wing hairs grow in a certain direction as a result of the orientation of the cells, making it easy for researchers to see problems in the pathway. A recent paper has found a role for a transmembrane proton pump protein called VhaPRR in PCP signaling. Images are election micrographs of bristles with (left) or without (right) normal levels of VhaPRR. Without VhaRRR, the bristles are disoriented, as well as the small epithelial hairs underneath.
Reference: Tobias Hermle, Deniz Saltukoglu, Julian Grünewald, Gerd Walz and Matias Simons. Current Biology 20(14): 253-258. ©2010 Elsevier Ltd. All rights reserved. Paper can be found here.