@article{FazeliStetterLisacketal.2018, author = {Fazeli, Gholamreza and Stetter, Maurice and Lisack, Jaime N. and Wehman, Ann M.}, title = {C. elegans Blastomeres Clear the Corpse of the Second Polar Body by LC3-Associated Phagocytosis}, series = {Cell Reports}, volume = {23}, journal = {Cell Reports}, doi = {10.1016/j.celrep.2018.04.043}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-227651}, pages = {2070-2082}, year = {2018}, abstract = {To understand how undifferentiated pluripotent cells cope with cell corpses, we examined the clearance of polar bodies born during female meiosis. We found that polar bodies lose membrane integrity and expose phosphatidylserine in Caenorhabditis elegans. Polar body signaling recruits engulfment receptors to the plasma membrane of embryonic blastomeres using the PI3K VPS-34, RAB-5 GTPase and the sorting nexin SNX-6. The second polar body is then phagocytosed using receptor-mediated engulfment pathways dependent on the Rac1 ortholog CED-10 but undergoes non-apoptotic programmed cell death independent of engulfment. RAB-7 GTPase is required for lysosome recruitment to the polar body phagosome, while LC3 lipidation is required for degradation of the corpse membrane after lysosome fusion. The polar body phagolysosome vesiculates in an mTOR- and ARL-8-dependent manner, which assists its timely degradation. Thus, we established a genetic model to study clearance by LC3-associated phagocytosis and reveal insights into the mechanisms of phagosome maturation and degradation.}, language = {en} } @phdthesis{Stetter2021, author = {Stetter, Maurice}, title = {LC3-associated phagocytosis seals the fate of the second polar body in \(Caenorhabditis\) \(elegans\)}, doi = {10.25972/OPUS-23198}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-231981}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2021}, abstract = {This work investigates the death and degradation of the second polar body of the nematode C. elegans in order to improve our understanding how pluripotent undifferentiated cells deal with dying cells. With the use of fluorescence microscopy this work demonstrates that both polar bodies loose membrane integrity early. The second polar body has contact to embryonic cells and gets internalized, dependent on the Rac1-ortholog CED-10. The polar body gets degraded via LC3-associated phagocytosis. While lysosome recruitment depends on RAB-7, LC3 does not improve lysosome recruitment but still accelerates polar body degradation. This work establishes the second polar body as a genetic model to study cell death and LC3-associated phagocytosis and has revealed further aspects of phagosome maturation and degradation.}, subject = {Polk{\"o}rper}, language = {en} }