The overexpression of SRSF9 alters the alternative splicing pattern of HIV-1 mRNA. HEK293T cells were co-transfected with 1 μg of pNL4-3GFP with Flag-tagged SRSF1 or Flag-tagged SRSF9. After 24 h, 1.5 μg of the extracted RNA was subjected to Northern blot using a DIG-labeled Env probe (A) and RT-qPCR assay using a Gag primer (B). The extracted RNA was subjected to RT-PCR using primers (presented with red arrows) to detect -4 kb mRNAs, and the produced -4 kb mRNA RT-PCR products are presented in the scheme (C). PCR products were separated on 6% denaturing polyacrylamide gel (D). The asterisks indicate a significant difference from control, analyzed by one-way ANOVA (*P < 0.05, **P < 0.005, and ***P < 0.001).
