Fiche publication


Date publication

avril 2024

Journal

Nucleic acids research

Auteurs

Membres identifiés du Cancéropôle Est :
Pr MOTORINE Iouri , Dr MARCHAND Virginie


Tous les auteurs :
Sudol C, Kilz LM, Marchand V, Thullier Q, Guérineau V, Goyenvalle C, Faivre B, Toubdji S, Lombard M, Jean-Jean O, de Crécy-Lagard V, Helm M, Motorin Y, Brégeon D, Hamdane D

Résumé

Dihydrouridine (D) is a common modified base found predominantly in transfer RNA (tRNA). Despite its prevalence, the mechanisms underlying dihydrouridine biosynthesis, particularly in prokaryotes, have remained elusive. Here, we conducted a comprehensive investigation into D biosynthesis in Bacillus subtilis through a combination of genetic, biochemical, and epitranscriptomic approaches. Our findings reveal that B. subtilis relies on two FMN-dependent Dus-like flavoprotein homologs, namely DusB1 and DusB2, to introduce all D residues into its tRNAs. Notably, DusB1 exhibits multisite enzyme activity, enabling D formation at positions 17, 20, 20a and 47, while DusB2 specifically catalyzes D biosynthesis at positions 20 and 20a, showcasing a functional redundancy among modification enzymes. Extensive tRNA-wide D-mapping demonstrates that this functional redundancy impacts the majority of tRNAs, with DusB2 displaying a higher dihydrouridylation efficiency compared to DusB1. Interestingly, we found that BsDusB2 can function like a BsDusB1 when overexpressed in vivo and under increasing enzyme concentration in vitro. Furthermore, we establish the importance of the D modification for B. subtilis growth at suboptimal temperatures. Our study expands the understanding of D modifications in prokaryotes, highlighting the significance of functional redundancy in this process and its impact on bacterial growth and adaptation.

Référence

Nucleic Acids Res. 2024 04 29;: