Essential roles of Gα12/13 signaling in distinct cell behaviors driving zebrafish convergence and extension gastrulation movements

G alpha(12/ 13) have been implicated in numerous cellular processes, however, their roles in vertebrate gastrulation are largely unknown. Here, we show that during zebrafish gastrulation, suppression of both G alpha(12) and G alpha(13) signaling by overexpressing dominant negative proteins and application of antisense morpholinomodified oligonucleotide translation interference disrupted convergence and extension without changing embryonic patterning. Analyses of mesodermal cell behaviors revealed that G alpha(12/13) are required for cell elongation and efficient dorsalward migration during convergence independent of noncanonical Wnt signaling. Furthermore, G alpha(12/13) function cell-autonomously to mediate mediolateral cell elongation underlying intercalation during notochord extension, likely acting in parallel to noncanonical Wnt signaling. These findings provide the first evidence that G alpha(12) and G alpha(13) have overlapping and essential roles in distinct cell behaviors that drive vertebrate gastrulation.