Figure 6: SLFN11-mediated type II tRNAs cleavage inhibits translation mRNAs of genes with high frequency of codon TTA (Leu) usage.

a, Volcano plot of fold change of all cellular tRNAs after 12 hours of 200 nM CPT or DMSO treatment in FG cells as determined by qPCR. b, as in a, except in FG SLFN11 knockout cells. (log2(mean of fold change) vs. p-Value; n = 3; p-Value was calculated by performing a two-tailed two-sample equal variance (homoscedastic) Student’s t-test.) c, tRNA Northern blot analysis of total RNA isolated from FG cells and FG SLFN11 knockout cells treated with 200 nM CPT or DMSO. d, tRNA Northern blot analysis of total RNA from HEK293T cells exogenously expressing control protein (CAT) or SLFN11. Samples were collected 48 hours after transfection. (Numbers indicate quantified band intensity relative to DMSO treated FG cell samples in c or relative to CAT-expressing HEK293T cell controls in d.; 5.8s rRNA served as the endogenous control for normalization) e, Prolonged exposure of tRNA Northern blots of total RNA from FG cells and FG SLFN11 knockout cells treated with 200 nM CPT or DMSO for 12 hours, revealing the cleaved tRNA fragments. f, Protein expression of EGFP encoded by constructs using only the indicated codon for all leucine or serine residues in HEK293T cells in the absence or presence of exogenous SLFN11 expression 48 hours after transfection as determined by anti-GFP immunoblotting. g, As in f, relative mRNA levels derived from indicated EGFP constructs were determined by qPCR (mean ± s.d.; n = 3). Uncropped images are shown in Supplementary Data Set 1.