Linking Planar Cell Polarity to Mechanotransduction During Morphogenesis

Mechanical forces provide essential cues for morphogenetic processes during embryonic development. Coordinated orientation of cells in the plane of epithelia, that is known as planar cell polarity (PCP), is also required for morphogenesis. How PCP is established and what role PCP signaling plays in tissue rearrangements remains poorly understood. Here, we review the evidence for a positive regulatory loop that connects PCP to mechanotransduction, the process by which cells convert mechanical stimuli, such as pressure or tension, into biochemical signals. Accumulating data strongly support a hypothesis that a PCP axis can form in response to intrinsic or extrinsic mechanical stresses. Moreover, we suggest that PCP signaling functions to control physical force production in the tissue. This mechanochemical feedback regulation is proposed to be a fundamental mechanism that ensures proper tissue shape and positioning during morphogenesis.