FIGURE 1.

Interaction of Rev with hnRNPs A1 and Q. hnRNP A1 and Q were identified as novel interactors of Rev by affinity chromatography of astrocytic cell lysates (U138MG) with immobilized Rev baits (A and B) and by co-immunoprecipitation (IP) assays (C). A, SDS-PAGE analysis of proteins captured from cell lysates with a bait peptide containing Rev AA 1–14 fused to the StrepTagII sequence. hnRNP Q and A1 were identified by MALDI-TOF mass spectrometry. B, Western blot analysis of proteins in cell lysates (L) and elution fraction (E) of affinity chromatography assays, using either Rev-containing bait proteins (RevGFP-StrepTagII = RGS) or bait proteins lacking the Rev sequence (GFP-StrepTagII = GS). Specific Rev interaction was demonstrated for hnRNP Q and A1 and for 5 known Rev-interactors (CRM1, Importin β, B23, Casein kinase 2, and eIF-5A). RNA-polymerase II and GAPDH showed no interaction with Rev. C, Western blot analysis of proteins in lysates and immunoprecipitates (P) from human cells stably expressing either the RGS or GS bait protein. Immunoprecipitations were performed with antibodies against GFP, and proteins were detected with specific antibodies. eIF-5A served as a control for a known Rev interactor and GAPDH as a control for a non-interacting protein.