Fig. 8: Functional investigations of TREX-2 and TREX-2.1 in mRNP metabolism.

a–j RNA features associated with cellular mRNAs whose nucleocytoplasmic distribution is influenced by LENG8. A549 cells were transfected with siRNAs that target LENG8 or with non-targeting control siRNAs. After 72 h, RNA was isolated from whole cell lysates and from nuclear or cytoplasmic fractions and subjected to RNAseq analysis. Two biological replicates were analyzed to identify mRNAs whose nuclear to cytoplasmic ratios are above 2.0 with no change in total expression levels. RNA features associated with cellular mRNAs whose nucleocytoplasmic ratio is modulated by LENG8 were compared to RNA features of the control genome-wide mRNA population. Violin plots show the distribution of the depicted RNA features between these two groups. The red line indicates the median, and the green line indicates quartiles. A two-tailed Mann–Whitney U rank test was used to calculate statistical significance. p-values are shown on the top of and the number of transcripts for each group are the following: a (control n = 19,340; LENG8-dependent n = 391), b (control n = 19,340; LENG8-dependent n = 391), c (control n = 19,340; LENG8-dependent n = 391), d (control n = 19,128; LENG8-dependent n = 391), e (control n = 19,340; LENG8-dependent n = 391), f (control n = 19,340; LENG8-dependent n = 391), g (control n = 19,128; LENG8-dependent n = 391), h (control n = 18,575; LENG8-dependent n = 383), i (control n = 19,340; LENG8-dependent n = 391), j (control n = 19,340; LENG8-dependent n = 391). k IAV NP disrupts TREX-2/TREX-2.1 interactions with DDX39B. In vitro GST pull-down was performed with purified recombinant proteins. The schematic for the experiment is shown on the left. GST-DDX39B was first preincubated with TREX-2^M or TREX-2.1, and then IAV NP was added to the pull-down reactions. IAV NP was observed to associate with GST-DDX39B and displace TREX-2^M or TREX-2.1, as shown in the right panel. This experiment has been repeated three times independently with similar results. Source Data are provided as a Source Data file.