Apoptosis Triggers Specific, Rapid, and Global mRNA Decay with 3' Uridylated Intermediates Degraded by DIS3L2.
Bottom Line: Apoptosis is a tightly coordinated cell death program that damages mitochondria, DNA, proteins, and membrane lipids.Little is known about the fate of RNA as cells die.Our results suggest that global mRNA decay is an overlooked hallmark of apoptosis.
Affiliation: Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA.Show MeSH
Related in: MedlinePlus
Mentions: We hypothesized that one or more TUTases add these non-templated uridylate-rich tails. We focused on ZCCHC6 and ZCCHC11 because they uridylate other cytosolic RNAs (Schmidt et al., 2011; Thornton et al., 2012, 2014). We transfected HeLa cells with a control siRNA or siRNAs targeting ZCCHC6 and/or ZCCHC11, or the TUTase PAPD7 (Figure 6A). Knockdown of ZCCHC6, ZCCHC11, or both reduced apoptotic 3′ uridylation of the ACTB mRNA (Figure 6B) and partially rescued mRNA levels after STS treatment (Figure 6C), whereas PAPD7 knock-down had no effect. ZCCHC6 and ZCCHC11 siRNAs, alone and in combination, reduced annexin V staining (Figure 6D) and caspase 3 cleavage and activation (Figures 6E and 6F) in response to STS. Again, PAPD7 siRNAs had no effect. Collectively, these results suggest that ZCCHC6 and ZCCHC11 collaborate to uridylate mRNAs during cell death, promoting mRNA decay and apoptosis.
Affiliation: Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA.