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Structural characterisation of TNRC6A nuclear localisation signal in complex with importin-alpha.

ABSTRACT: The GW182/TNRC6 family of proteins are central scaffolds that link microRNA-associated Argonaute proteins to the cytoplasmic decay machinery for targeted mRNA degradation processes. Although nuclear roles for the GW182/TNRC6 proteins are unknown, recent reports have demonstrated nucleocytoplasmic shuttling activity that utilises the importin-? and importin-? transport receptors for nuclear translocation. Here we describe the structure of mouse importin-? in complex with the TNRC6A nuclear localisation signal peptide. We further show that the interactions observed between TNRC6A and importin-? are conserved between mouse and human complexes. Our results highlight the ability of monopartite cNLS sequences to maximise contacts at the importin-? major binding site, as well as regions outside the main binding cavities.

SUBMITTER: Chaston JJ

PROVIDER: S-EPMC5570423 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Structural characterisation of TNRC6A nuclear localisation signal in complex with importin-alpha.

Chaston Jessica J JJ Stewart Alastair Gordon AG Christie Mary M

PloS one 20170824 8

The GW182/TNRC6 family of proteins are central scaffolds that link microRNA-associated Argonaute proteins to the cytoplasmic decay machinery for targeted mRNA degradation processes. Although nuclear roles for the GW182/TNRC6 proteins are unknown, recent reports have demonstrated nucleocytoplasmic shuttling activity that utilises the importin-α and importin-β transport receptors for nuclear translocation. Here we describe the structure of mouse importin-α in complex with the TNRC6A nuclear locali ...[more]

PMID: 28837617

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