Figure EV3. TUT4 can uridylate tRNAs and TUT4 activity enhances tRNA degradation by DIS3L2.

1. In vitro uridylation assay with TUTases 4, 6, and 7 purified from human cells and a Leu tRNA fragment (tRFLeu) as a template.
2. Coupled, in vitro uridylation/degradation assay. 5′‐end‐labeled tRFLeu was incubated with wild‐type (WT) or catalytically inactive (DADA) TUT4 for 40 min in the presence of 0.25 mM UTP. Subsequently, the WT or mutant DIS3L2 was added and the reactions were stopped after times indicated at the top of the panel. The RNAs were resolved on 20% denaturing acrylamide gel, and radioactivity was detected by autoradiography. The migration position of the input tRFLeu, the uridylated forms and the degradation products, is marked on the left side.