Cell paper with Nobel Laureate for Kenn Gerdes
The Structural Basis for mRNA Recognition and Cleavage by the Ribosome-Dependent Endonuclease RelE
Cajetan Neubauer, Yong-Gui Gao, Kasper R. Andersen, Christine M. Dunham, Ann C. Kelley, Jendrik Hentschel, Kenn Gerdes, V. Ramakrishnan, and Ditlev E. BrodersenCell 139, 1084–1095, December 11, 2009 ª2009 Elsevier Inc.
SUMMARY
Translational control is widely used to adjust gene expression levels. During the stringent response in bacteria, mRNA is degraded on the ribosome by the ribosome-dependent endonuclease, RelE. The molecular basis for recognition of the ribosome and mRNA by RelE and the mechanism of cleavage are unknown. Here, we present crystal structures of E. coli RelE in isolation (2.5 A°) and bound to programmed Thermus thermophilus 70S ribosomes before (3.3 A°) and after (3.6 A°) cleavage. RelE occupies the A site and causes cleavage of mRNA after the second nucleotide of the codon by reorienting and activating the mRNA for 20-OH-induced hydrolysis. Stacking of A site codon bases with conserved residues in RelE and 16S rRNA explains the requirement for the ribosome in catalysis and the subtle sequence specificity of the reaction. These structures provide detailed insight into the translational regulation on the bacterial ribosome by mRNA cleavage.
published on: 11th December 2009
