Poccia, D.L. (2016)  A Sea Urchin Cell-Free System to Study Male Pronuclear Assembly and Activation. 
Int. J. Dev. Biol. 60: 209-219.

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We have studied the reactivation of sperm nuclei in a cell-free system derived from homogenates of activated egg cytoplasm. 

Sea Urchin 2.jpg The cell-free system has provided several novel insights including requirements for sperm-specific histone phosphorylation on N- and C-terminal extensions and disassembly of the sperm nuclear lamina for decondensation, the utilization of remnant regions of the sperm nuclear envelope to direct polarized binding and fusion of egg membranes to form the new nuclear envelope, and a role for phosphoinositide metabolism in initiation of membrane fusion through binding of a minor membrane fraction enriched in PtdIns (4,5)P2, PLCγ and SFK1 which locally produce a fusigenic lipid, diacylglycerol.

 

 

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