LANA enhances the inhibitory function of STAT6 on transcription of RTA through STAT6-binding sites within RTA promoter.

(A) Schematic of putative STAT6-binding sites within RTA and LANA promoters. The RTA (or LANA) promoter-driven luciferase reporters RTAp-Luc (or LANAp-Luc) are shown at the bottom panel. LANA enhances the inhibitory function of STAT6 on transcription of RTA promoter (B) but not LANA promoter (C). HEK293 cells co-transfected with the indicated promoter-reporters combination with full-length (FL) STAT6 or its mutants in the presence or absence of LANA were subjected to reporter assay. Relative luciferase unit (RLU) normalization with Rellina activity was analyzed. Data is presented as meansαSD of three independent experiments. Asterisks indicate P value as follows: *, P>0.05, and **, P<0.05. (D) Knockdown of STAT6 abolishes the inhibitory function of LANA on RTA transcription. HeLa cells co-transfected with the indicated plasmids in the presence of RTAp-luc reporter, were subjected to reporter assays as described in panel B.