Extended Data Fig. 1: Protein/RNA purification and cryo-EM sample preparation.
a Size−exclusion chromatogram and SDS-PAGE analysis of the last step of the purification of full-length METTL6 (column: Superdex 75 16/600); representative chromatogramme and gel from more than three replicates. b Size-exclusion chromatogram and SDS-PAGE analysis of the last step of the purification of full-length SerRS (Column: Superdex 200 10/300); representative chromatogramme and gel from more than three replicates. c Sequence (left) and quality control of in vitro transcribed tRNASerUGA on denaturing urea PAGE (left) and native PAGE (right); representative gels from more than three replicates. d In vitro methylation activity measurements of METTL6 in the presence of SerRS, tRNASerUGA and/or L-Serine and ATP. Data is represented as the blank-subtracted mean and standard deviation of independent replicates (n = 3). e Complex formation of SerRS, tRNASerUGA and METTL6 on analytical size-exclusion chromatography (Column: Superdex 200 3.2/300); representative chromatogramme and gel from one or more replicates. Fractions were analysed for protein and RNA contents using SDS-PAGE and urea PAGE. f Cartoon representation of crystal structures from this study: apo-METTL6 full-length (pdb:8OWX) and apo-METTL6 40–269 (pdb 8OWY) in complex with SAH.
