TUT1 suppression yields broad decreases in miRNA expression.

<p>We performed miRNA profiling to determine the effect of suppressing nucleotidyl transferase enzymes in HCT-116 cells on miRNA abundance. (<b>A</b>) We compared the abundance of miRNAs detectable with at least 50 counts on the NanoString platform in the enzyme suppressed vs. negative control siRNA-transfected cells. Boxplots depict miRNA expression relative to negative control cells, which are depicted by the horizontal line at 1. Three enzymes–TUT1, PAPD4, and MTPAP–showed a significant, broad decrease in miRNA abundance (t-test, p-value <1×10⁻¹⁰). (<b>B</b>) Boxplots depict the average miRNA expression values from qRT-PCR profiling of over 300 miRNAs in the enzyme-suppressed and negative control cells. In this independent sample set, we found that suppression of TUT1 and PAPD4 lead to highly significant decreases in the abundance of the vast majority of miRNAs analyzed (t-test p-value <1×10⁻³⁰ for both enzymes). (<b>C</b>) Suppression of TUT1 in A549 lung carcinoma cells yields decreased miRNA abundance. qRT-PCR arrays were used to compare the global miRNA expression levels in A549 cells transfected with siRNAs against TUT1 or a control nucleotidyl transferase, ZCCHC11, versus negative-control treated cells. A549 cells showed a significant reduction in miRNA abundance following TUT1 suppression (t-test, p-value <1×10⁻²⁰), while ZCCHC11 suppression did not affect miRNA levels.