Gene loss-of-function and live imaging in chick embryos.

Planar cell polarity (PCP) is the coordinate organization of cells within the plane of a tissue. PCP is essential for tissue function, such as for proper hearing in the vertebrate ear or for accurate vision in the Drosophila eye. Using the chick embryo, we have recently shown that during early muscle formation, the first formed muscle fibres utilize the PCP pathway to orient parallel to a WNT11 source present in the medial border of somites. Our results further establish that WNT11 acts as a directional cue to regulate this process. To perform this study, two major techniques have been utilized, the gene loss-of-function using a vector-based shRNAmir expression and confocal videomicroscopy of fluorescent gene reporters targeted in specific cell subpopulations by in vivo electroporation. Here we describe the two techniques.