Topic: Biosynthetic Mechanisms of tRNA t⁶A in Bacteria, Archaea and Eukaryota

Speaker: Wenhua Zhang, Professor

Time: 10:00-11:30; May 15, 2025

Venue: International Meeting Hall 121-1

Abstract:

N⁶-threonylcarbamoyladenosine (t⁶A) is an essential and universal post-transcriptional modification present at position 37 of tRNAs that decode codons beginning with an adenine. t⁶A pre-organizes the anticodon loop of tRNAs in a conformation that enhances the binding to the cognate mRNA codons, thereby promoting the codon-biased translation. The lack of tRNA t⁶A leads to translation errors, compromises proteostasis and cell viability, interferes with the growth and development of higher eukaryotes and is implicated in several human diseases. The biogenesis of tRNA t⁶A had remained a mystery for 40 years since the discovery in 1960s. Over the past decade, major breakthroughs have been made toward understanding the biosynthetic pathways of tRNA t⁶A in the three domains of life. In this seminar, I will describe the molecular functions, cellular roles and the biosynthetic mechanisms of tRNA t⁶A in Bacteria, Archaea and Eukaryota. It’s my hope that this talk can put into a perspective the biochemical data, structures, catalytic mechanisms and biological functions.

Introduction:

Wenhua Zhang received his 2014 PhD in Molecular Biophysics with H. van Tilbeurgh from Université Paris-Saclay (Université Paris-Sud 11), Orsay, France. Upon completing 3 years postdoctoral training with J. Cherfils in French CNRS, Paris, France, he joined Lanzhou University School of Life Sciences and was appointed a professorship in Biophysics. His lab is focused on studying the biosynthetic mechanisms and the cellular roles of tRNA N⁶-threonylcarbamoyladenosine (t⁶A) and the t⁶A family modifications. He is one of the primary researchers in this field and published several seminal papers in J. Mol. Biol., J. Biol. Chem. and Nucleic Acids Res.