TRMT112 functions as a critical activator subunit for multiple RNA and protein methyltransferases, forming heterodimeric complexes that catalyze diverse methylation reactions essential for cellular function. The protein acts as a regulatory hub, stabilizing and activating various methyltransferase partners including METTL5, BUD23/WBSCR22, THUMPD3, and N6AMT1/HEMK2 123. Together with METTL5, TRMT112 specifically methylates adenine at position 1832 of 18S rRNA (m6A1832), which facilitates ribosome assembly and enhances translation of mRNAs containing 5' terminal oligopyrimidine motifs 14. The TRMT112-BUD23/WBSCR22 complex methylates guanosine at the N7 position in 18S rRNA and is required for pre-rRNA processing steps leading to small ribosomal subunit production 2. Additionally, TRMT112 partners with THUMPD3 to catalyze N2-methylguanosine formation at position 6 in various tRNAs, which is important for protein synthesis and cell proliferation 3. The protein also exhibits tumor suppressor activity in pancreatic cancer through transcriptional regulation of ISG15 5. TRMT112's diverse methyltransferase partnerships and essential roles in ribosome biogenesis and translation regulation make it a critical component of cellular RNA modification machinery.