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Conservation of proteo-lipid nuclear membrane fusion machinery during early embryogenesis.

ABSTRACT: The fusogenic lipid diacylglycerol is essential for remodeling gamete and zygote nuclear envelopes (NE) during early embryogenesis. It is unclear whether upstream signaling molecules are likewise conserved. Here we demonstrate PLC? and its activator SFK1, which co-operate during male pronuclear envelope formation, also promote the subsequent male and female pronuclear fusion. PLC? and SFK1 interact directly at the fusion site leading to PLC? activation. This is accompanied by a spatially restricted reduction of PtdIns(4,5)P2. Consequently, pronuclear fusion is blocked by PLC? or SFK1 inhibition. These findings identify new regulators of events in the early embryo and suggest a conserved "toolkit" of fusion machinery drives successive NE fusion events during embryogenesis.

SUBMITTER: Byrne RD

PROVIDER: S-EPMC4164486 | biostudies-literature | 2014 Sep-Oct

REPOSITORIES: biostudies-literature

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Conservation of proteo-lipid nuclear membrane fusion machinery during early embryogenesis.

Byrne Richard D RD Veeriah Selvaraju S Applebee Christopher J CJ Larijani Banafshé B

Nucleus (Austin, Tex.) 20140901 5

The fusogenic lipid diacylglycerol is essential for remodeling gamete and zygote nuclear envelopes (NE) during early embryogenesis. It is unclear whether upstream signaling molecules are likewise conserved. Here we demonstrate PLCγ and its activator SFK1, which co-operate during male pronuclear envelope formation, also promote the subsequent male and female pronuclear fusion. PLCγ and SFK1 interact directly at the fusion site leading to PLCγ activation. This is accompanied by a spatially restric ...[more]

PMID: 25482196

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