Essential roles of Gα_12/13 signaling in distinct cell behaviors driving zebrafish convergence and extension gastrulation movements

Gα_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 Gα₁₂ and Gα₁₃ signaling by overexpressing dominant negative proteins and application of antisense morpholino-modified oligonucleotide translation interference disrupted convergence and extension without changing embryonic patterning. Analyses of mesodermal cell behaviors revealed that Gα_12/13 are required for cell elongation and efficient dorsalward migration during convergence independent of noncanonical Wnt signaling. Furthermore, Gα_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 Gα₁₂ and Gα₁₃ have overlapping and essential roles in distinct cell behaviors that drive vertebrate gastrulation.