Explore
Home 
Literature 
Links 
Posts 
Molecules 
Blogs 
Zeitgeist 
Markup Help 
News 
Everything Papers Books
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 2'-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.

Posts

This is officially the first time I actually say something "serious" about science on this blog. I don't know if there are any who will read this who will have the knowledge to even understand this, but I mainly want to record this somewhere in the off case...