Distinct RhoGEFs activate apical and junctional actomyosin contractility under control of G proteins during epithelial morphogenesis

摘要: Abstract Small RhoGTPases and Myosin-II direct cell shape changes movements during tissue morphogenesis. Their activities are tightly regulated in space time to specify the desired pattern of contractility that supports This is expected stem from polarized surface stimuli signaling processing inside cells. We examined this general problem context intercalation drives extension Drosophila ectoderm. In ectoderm, G protein coupled receptors (GPCRs) their downstream heterotrimeric proteins (Gα Gβγ) activate Rho1 both medial-apically, where it exhibits pulsed dynamics, at junctions, its activity planar (Kerridge et al., 2016; Munjal 2015). However, mechanisms responsible for polarizing unclear. particular, unknown how controlled junctions. report a division labor activation distinct guanine exchange factors (GEFs), serve as activators Rho1, operate these cellular compartments. RhoGEF2 acts uniquely medial-apical Rho1. Although recruited medial-apically junctions by Gα12/13-GTP, also called Concertina (Cta) Drosophila, restricted compartment. Furthermore, we characterize novel RhoGEF, p114RhoGEF/Wireless (Wrl), requirement extending activates specifically Strikingly adherens under Gβ13F/Gγ1 control. junctional exerts quantitative control over polarization overexpression leads hyper MyoII. Finally, found absent mesoderm, arguing tissue-specific activity. These results shed light on different compartments reveal GEFs sensitive tuning parameters remodeling epithelia.