Background HIV-1 gene expression and replication are regulated at several levels. Incompletely spliced viral RNAs and full length genomic RNA contain the RRE element and are bound by the viral trans-acting protein Rev to be transported out of the nucleus. Previously, we found, through a novel proteomic approach, that the nuclear matrix protein MATR3 is a cofactor of Rev mediated RNA export [Kula A et al.: Retrovirology 2011, 8:60]. More recently we demonstrated that pleiotropic polypyrimidine tract binding protein associated splicing factor (PSF) binds viral RNA and is associated with MATR3 [Kula A., Gharu L, Marcello A: Virology 2013, 435(2): 329-340].