Selective Chemical Manipulation of Mannosyl- and Galactosyl-Queuosine in tRNAs of Living Cells.

ABSTRACT: Queuosine is a hypermodified nucleoside found in the anticodon loop of tRNAs decoding the amino acids His, Asn, Tyr, and Asp. In tRNA^Tyr, the homoallylic 2-hydroxyl group of the cyclopentene ring carries an additional β-galactose, while in tRNA^Asp, an α-mannose is connected to the allylic 3-hydroxyl group. Although these additional sugar modifications were found in the tRNAs of many animals, including humans, their purpose remains unknown. Recently, the Q-tRNA galatosyl- and mannosyltransferase (QTGAL and QTMAN) that attach the galactose and mannose moieties to the different OH groups of the Q-base have been identified, but the function of this transfer reaction remains unclear. Here, we performed feeding experiments with synthetic deoxyqueuine derivatives that lack e

SUBMITTER: Pichler A 

PROVIDER: S-EPMC12518689 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature