Rab8 directs furrow ingression and membrane addition during epithelial formation in Drosophila melanogaster

• DOI: 10.1242/dev.128876
• Publication Date: 2016-02-03T01:50:31Z
• Authors: Lauren M. Mavor; Hui Miao; Zhongyuan Zuo; Ryan M. Holly; Yi Xie; Dinah Loerke; J. Todd Blankenship
• Keywords: Exocyst; Ingression; Cell membrane; Cleavage furrow

One of the most fundamental changes in cell morphology is ingression a plasma membrane furrow. The Drosophila embryo undergoes several cycles rapid furrow during early development that culminates formation an epithelial sheet. Previous studies have demonstrated requirement for intracellular trafficking pathways ingression; however, link compartmental behaviors with cortical events remained unclear. Here, we show Rab8 has striking dynamic vivo. As furrows ingress, cytoplasmic puncta are depleted and accumulates at location coincides known regions directed addition. We additionally use CRISPR/Cas9 technology to N-terminally tag Rab8, which then used address both endogenous localization function. Endogenous displays partial coincidence Rab11 Golgi, this colocalization enriched fast phase cellularization. When function disrupted, completely abolished. also demonstrate require exocyst complex subunit Sec5 as well recycling endosome Rab11. Active, GTP-locked primarily associated compartments membrane, while GDP-locked forms large aggregates. These suggest model active populations direct by guiding targeted delivery stores surface through tethering interactions.