Kaltschmidt, J.A., Lawrence, N., Morel, V., Balayo, T., Fernandez, B.G., Pelissier, A., Jacinto, A., Martinez Arias, A. (2002). Planar polarity and actin dynamics in the epidermis of Drosophila.  Nat. Cell Biol. 4(12): 937--944.

FBrf0155993

Research paper

Dorsal closure is a morphogenetic process involving the coordinated convergence of two epithelial sheets to enclose the Drosophila melanogaster embryo. Specialized populations of cells at the edges of each epithelial sheet, the dorsal-most epidermal cells, emit actin-based processes that are essential for the proper enclosure of the embryo. Here we show that actin dynamics at the leading edge is preceded by a planar polarization of the dorsal-most epidermal cells associated with a reorganization of the cytoskeleton. An important consequence of this planar polarization is the formation of actin-nucleating centres at the leading edge, which are important in the dynamics of actin. We show that Wingless (Wg) signalling and Jun amino-terminal kinase (JNK) signalling have overlapping but different roles in these events.