Inhibition of splicing by serine-arginine rich protein 55 (SRp55) causes the appearance of partially spliced HIV-1 mRNAs in the cytoplasm

Department of Medical Biochemistry & Microbiology, Uppsala University, BMC, 75123 Uppsala, Sweden.
Virus Research (Impact Factor: 2.83). 02/2011; 157(1):82-91. DOI: 10.1016/j.virusres.2011.02.010
Source: PubMed

ABSTRACT We have previously shown that SRp55 inhibits splicing from HIV-1 exon 3, thereby generating partially spliced mRNAs encoding HIV-1 vpr. Here we show that SRp55 also inhibits splicing from HIV-1 exon 5 to generate HIV-1 vpu/env mRNA, albeit with lower efficiency. We also show that inhibition of HIV-1 splicing by SRp55 causes the appearance of partially spliced vpu, env and vpr mRNAs in the cytoplasm. SRp55 could also induce production of extracellular p24gag from a rev-defective HIV-1 provirus. These results indicate that SRp55 aids in the generation of partially spliced and unspliced HIV-1 mRNAs.

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