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Poliovirus 2A protease triggers a selective nucleo-cytoplasmic redistribution of splicing factors to regulate alternative pre-mRNA splicing.

ABSTRACT: Poliovirus protease 2A (2A(pro)) obstructs host gene expression by reprogramming transcriptional and post-transcriptional regulatory events during infection. Here we demonstrate that expression of 2A(pro) induces a selective nucleo-cytoplasm translocation of several important RNA binding proteins and splicing factors. Subcellular fractionation studies, together with immunofluorescence microscopy revealed an asymmetric distribution of HuR and TIA1/TIAR in 2A(pro) expressing cells, which modulates splicing of the human Fas exon 6. Consistent with this result, knockdown of HuR or overexpression of TIA1/TIAR, leads to Fas exon 6 inclusion in 2A(pro)-expressing cells. Therefore, poliovirus 2A(pro) can target alternative pre-mRNA splicing by regulating protein shuttling between the nucleus and the cytoplasm.

SUBMITTER: Alvarez E

PROVIDER: S-EPMC3774746 | biostudies-other | 2013

REPOSITORIES: biostudies-other

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Poliovirus 2A protease triggers a selective nucleo-cytoplasmic redistribution of splicing factors to regulate alternative pre-mRNA splicing.

Álvarez Enrique E Castelló Alfredo A Carrasco Luis L Izquierdo José M JM

PloS one 20130916 9

Poliovirus protease 2A (2A(pro)) obstructs host gene expression by reprogramming transcriptional and post-transcriptional regulatory events during infection. Here we demonstrate that expression of 2A(pro) induces a selective nucleo-cytoplasm translocation of several important RNA binding proteins and splicing factors. Subcellular fractionation studies, together with immunofluorescence microscopy revealed an asymmetric distribution of HuR and TIA1/TIAR in 2A(pro) expressing cells, which modulates ...[more]

PMID: 24066065

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