Mechano-chemical regulation of endocytosis in the developing C. elegans oocyte

During oocyte maturation, the Caenorhabditis elegans oocyte prepares for fertilization and its first cell division by rapidly remodelling its actomyosin cortex (~ 10 minutes). This period is also marked by intense endocytic activity. Using live-cell imaging, we observed the assembly and disassembly of branched actin structures that co-localize with endocytic proteins such as clathrin and dynamin, and that respond sensitively to perturbations targeting endocytosis. Importantly, we observe a morphological transition from micron-scale ring-like morphologies (∼2 µm diameter) to submicron punctate morphology just as the actomyosin cortex is activated. Thus our system provides us an opportunity to study how the mechanical and chemical state of the actomyosin cortex modulates endocytic organization during oocyte maturation? We will describe our ongoing efforts to quantify these mechanochemical feedback processes using micropipette aspiration, controlled cortical perturbations, and quantitative image analysis.