The function of ENSG00000059588 (TARBP1, tRNA guanosine 2 -O-methyltransferase TARBP1) is as follows. S-adenosyl-L-methionine-dependent 2'-O-ribose methyltransferase that catalyzes the formation of 2'-O-methylguanosine at position 18 (Gm18) in a subset of tRNA (PubMed:18412263, PubMed:31019095, PubMed:38867004). Selectively mediates Gm18 methylation of tRNAGln-TTG/CTG and tRNASer-TGA/GCT. Gm18 modification can enhance the stability of modified tRNAs (PubMed:38867004). {ECO:0000269|PubMed:18412263, ECO:0000269|PubMed:31019095, ECO:0000269|PubMed:38867004}. (Microbial infection) In case of infection by HIV-1, it binds to the loop region of TAR RNA, a region also bound by RNA polymerase II (PubMed:7638159, PubMed:8626763, PubMed:8846792). Binding of TARBP1 and RNA polymerase II to HIV-1 TAR RNA is mutually exclusive, suggesting that TARBP1 may function alone or in conjunction with HIV-1 Tat to disengage RNA polymerase II from HIV-1 TAR RNA (PubMed:7638159, PubMed:8626763, PubMed:8846792). {ECO:0000269|PubMed:7638159, ECO:0000269|PubMed:8626763, ECO:0000269|PubMed:8846792}.