Complexin I is required for mammalian sperm acrosomal exocytosis Export

@article{citeulike:1675039, abstract = {Regulated exocytosis in many cells is controlled by the SNARE complex, whose core includes three proteins that promote membrane fusion. Complexins I and II are highly related cytosolic proteins that bind tightly to the assembled SNARE complex and regulate neuronal exocytosis. Like somatic cells, sperm undergo regulated exocytosis; however, sperm release a single large vesicle, the acrosome, whose release has different characteristics than neuronal exocytosis. Acrosomal release is triggered upon sperm adhesion to the mammalian egg extracellular matrix (zona pellucida) to allow penetration of the egg coat. Membrane fusion occurs at multiple points within the acrosome but how fusion is activated and the formation and progression of fusion points is synchronized is unclear. We show that complexins I and II are found in acrosome-intact mature sperm, bind to SNARE complex proteins, and are not detected in sperm after acrosomal exocytosis (acrosome reaction). Although complexin-I-deficient sperm acrosome-react in response to calcium ionophore, they do not acrosome-react in response to egg zona pellucida proteins and have reduced fertilizing ability, in vitro. Complexin II is present in the complexin-I-deficient sperm and its expression is increased in complexin-I-deficient testes. Therefore, complexin I functions in exocytosis in two related but morphologically distinct secretory processes. Sperm are unusual because they express both complexins I and II but have a unique and specific requirement for complexin I.}, author = {Zhao, Longmei and Burkin, Heather R. and Shi, Xudong and Li, Lingjun and Reim, Kerstin and Miller, David J.}, citeulike-article-id = {1675039}, citeulike-linkout-0 = {http://dx.doi.org/10.1016/j.ydbio.2007.07.009}, citeulike-linkout-1 = {http://www.sciencedirect.com/science/article/B6WDG-4P7787H-4/2/e4f210eff7c12c09f031fa18b5120b58}, day = {15}, doi = {10.1016/j.ydbio.2007.07.009}, journal = {Developmental Biology}, keywords = {acrosome, acrosome-reaction, fertilisation, fertility, sperm}, month = {September}, number = {2}, pages = {236--244}, posted-at = {2007-09-19 09:55:15}, priority = {2}, title = {Complexin I is required for mammalian sperm acrosomal exocytosis}, url = {http://dx.doi.org/10.1016/j.ydbio.2007.07.009}, volume = {309}, year = {2007} }

TY - JOUR ID - citeulike:1675039 L3 - citeulike-article-id:1675039 N2 - Regulated exocytosis in many cells is controlled by the SNARE complex, whose core includes three proteins that promote membrane fusion. Complexins I and II are highly related cytosolic proteins that bind tightly to the assembled SNARE complex and regulate neuronal exocytosis. Like somatic cells, sperm undergo regulated exocytosis; however, sperm release a single large vesicle, the acrosome, whose release has different characteristics than neuronal exocytosis. Acrosomal release is triggered upon sperm adhesion to the mammalian egg extracellular matrix (zona pellucida) to allow penetration of the egg coat. Membrane fusion occurs at multiple points within the acrosome but how fusion is activated and the formation and progression of fusion points is synchronized is unclear. We show that complexins I and II are found in acrosome-intact mature sperm, bind to SNARE complex proteins, and are not detected in sperm after acrosomal exocytosis (acrosome reaction). Although complexin-I-deficient sperm acrosome-react in response to calcium ionophore, they do not acrosome-react in response to egg zona pellucida proteins and have reduced fertilizing ability, in vitro. Complexin II is present in the complexin-I-deficient sperm and its expression is increased in complexin-I-deficient testes. Therefore, complexin I functions in exocytosis in two related but morphologically distinct secretory processes. Sperm are unusual because they express both complexins I and II but have a unique and specific requirement for complexin I. IS - 2 JF - Developmental Biology EP - 244 TI - Complexin I is required for mammalian sperm acrosomal exocytosis VL - 309 SP - 236 KW - acrosome KW - acrosome-reaction KW - fertilisation KW - fertility KW - sperm AU - Zhao, Longmei AU - Burkin, Heather AU - Shi, Xudong AU - Li, Lingjun AU - Reim, Kerstin AU - Miller, David PY - 2007/09/15/ UR - http://dx.doi.org/10.1016/j.ydbio.2007.07.009 ER -