Required for the formation of N(7)-methylguanine at position 46 (m7G46) in tRNA, a modification required to maintain stability of tRNAs; its absence resulting in tRNA decay. In the complex, it is required to stabilize and induce conformational changes of the catalytic subunit. tRNA modification; N(7)-methylguanine-tRNA biosynthesis. Forms a heterodimer with the catalytic subunit TRM8. Belongs to the WD repeat TRM82 family.