Cell motility is regulated by extracellular cues and by intracellular factors that accumulate at sites of contact between cells and the extracellular matrix. One of these factors, focal adhesion kinase (FAK), regulates the cycle of focal adhesion formation and disassembly that is required for cell movement to occur. Recently, Wnt signaling has also been implicated in the control of cell movement in vertebrates, but the mechanism through which Wnt proteins influence motility is unclear. We demonstrate that Drosphila Wnt4 is required for cell movement and FAK regulation during ovarian morphogenesis. Dfrizzled2, Disheveled, and protein kinase C are also required. The DWnt4 cell motility pathway is distinct from both the canonical Wnt pathway and the planar polarity pathway. Our data suggest that DWnt4 facilitates motility through regulation of focal adhesions.

Hox complex genes are key developmental regulators highly conserved throughout evolution. The encoded proteins share a 60-amino-acid DNA-binding motif, the homeodomain, and function as transcription factors to control axial patterning. An important question concerns the nature and function of genes acting downstream of Hox proteins. This review focuses on Drosophila, as little is known about this question in other organisms. The noticeable progress gained in the field during the past few years has significantly improved our current understanding of how Hox genes control diversified morphogenesis. Here we summarise the strategies deployed to identify Hox target genes and discuss how their function contributes to pattern formation and morphogenesis. The regulation of target genes is also considered with special emphasis on the mechanisms underlying the specificity of action of Hox proteins in the whole animal.