Fig. 5: Designing a miniature NSUN2 RNA substrate.
From: Substrate selectivity of the human RNA m5C methyltransferase NSUN2
a, Schematics of tRNALysTTT variants. The 11-nt ssRNA ‘Oligo’ segment spans the region marked in blue, and ‘AC-arm’ refers to the anticodon arm. Mutations are coloured red, and compensatory mutations to preserve base pairing are coloured grey. b, In vitro methylation activity of NSUN2 with tRNA substrates shown in a (light grey) and Extended Data Fig. 6a (dark grey). The dashed line separates the two mutagenesis series. RNA sequence following the methylated Cyt (arrow) is shown on the right with position numbers. Data are shown as mean ± s.d. (n = 3, two-tailed unpaired t-test). c, Schematics of tRNALysTTT with arm deletions. d,e, In vitro methylation activity of NSUN2 (d) and the m7G methyltransferase METTL1–WDR4 complex (e) with the tRNAs from c. Significance tests are comparisons with wild-type tRNALysTTT. Data are shown as mean ± s.d. (n = 3, two-tailed unpaired t-test). f, Schematics of Mini NSUN2 substrate derived from NSUN2C271A–tRNALysTTT structures. g, In vitro methylation activity of NSUN2 with Mini (f), with additional deletions or modifications as described. Data are shown as mean ± s.d. (n = 3, two-tailed unpaired t-test). h,i, Schematics of two variants of Mini (f), with a closed C-stem and open bulge (h) or open N-loop (i). Ctr, no enzyme control.
