Effect of LPLA-2 Knockdown on Polar Body Membrane Breakdown

The 2nd polar body is phagocytosed embryo development, but it is not known how the polar body membrane is broken down inside the phagosome. Polar bodies are cellular byproducts of oogenesis born during meiosis that undergo non-apoptotic programmed cell death. After the polar body is internalized, the phagosome creates a second membrane around the cell corpse, in this case the polar body, separating the corpse from the cytosol. In order for the corpse contents to be degraded within the safety of the phagosome membrane, the corpse membrane must be selectively degraded. LPLA-2 is a lipase protein essential for breakdown of the inner autophagosome membrane during autophagy in Caenorhabditis elegans. In macroautophagy autophagosomes degrade cytoplasmic content. Given its essential role in a similar pathway, the question arises: what is LPLA-2’s role in polar body membrane breakdown? In order to determine the role LPLA-2 during polar body membrane breakdown, 4D movies of OP50-fed early C. elegans embryos were captured with a degron-tagged red fluorescent membrane marker mCherry::PHPLC1∂1::CTPD. The timing between polar body internalization and membrane breakdown was measured and this was used as the control. To compare regulated membrane breakdown RNAi was performed to knock down lpla-2. Resulting data shows no significance when comparing the timing of membrane breakdown of the OP50-fed embryos to the lpla-2 RNAi embryos. This contradicts the expectation that LPLA-2 facilitates corpse membrane breakdown and suggest that LPLA-2 is not likely to facilitate corpse membrane breakdown.