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Nuclear envelope budding enables large ribonucleoprotein particle export during synaptic Wnt signaling.

ABSTRACT: Localized protein synthesis requires assembly and transport of translationally silenced ribonucleoprotein particles (RNPs), some of which are exceptionally large. Where in the cell such large RNP granules first assemble was heretofore unknown. We previously reported that during synapse development, a fragment of the Wnt-1 receptor, DFrizzled2, enters postsynaptic nuclei where it forms prominent foci. Here we show that these foci constitute large RNP granules harboring synaptic protein transcripts. These granules exit the nucleus by budding through the inner and the outer nuclear membranes in a nuclear egress mechanism akin to that of herpes viruses. This budding involves phosphorylation of A-type lamin, a protein linked to muscular dystrophies. Thus nuclear envelope budding is an endogenous nuclear export pathway for large RNP granules.

SUBMITTER: Speese SD

PROVIDER: S-EPMC3371233 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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Nuclear envelope budding enables large ribonucleoprotein particle export during synaptic Wnt signaling.

Speese Sean D SD Ashley James J Jokhi Vahbiz V Nunnari John J Barria Romina R Li Yihang Y Ataman Bulent B Koon Alex A Chang Young-Tae YT Li Qian Q Moore Melissa J MJ Budnik Vivian V

Cell 20120501 4

Localized protein synthesis requires assembly and transport of translationally silenced ribonucleoprotein particles (RNPs), some of which are exceptionally large. Where in the cell such large RNP granules first assemble was heretofore unknown. We previously reported that during synapse development, a fragment of the Wnt-1 receptor, DFrizzled2, enters postsynaptic nuclei where it forms prominent foci. Here we show that these foci constitute large RNP granules harboring synaptic protein transcript ...[more]

PMID: 22579286

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Lamin Mutations Accelerate Aging via Defective Export of Mitochondrial mRNAs through Nuclear Envelope Budding.

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Torsin mediates primary envelopment of large ribonucleoprotein granules at the nuclear envelope.

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