A stalled ribosome (Dark Blue) is rescued through translation of the tmRNA ORF (Magenta). Proper positioning of this region of tmRNA in the A-site is achieved by the C-terminal tail of SmpB (Yellow) which is connected to the body of the SmpB protein (Orange) by a flexible glycine residue (Yellow gymnast). Generated with PDB files 4ABR, 4ABS, and 3J18.
Although I usually don't use this blog to herald my own accomplishments (i.e. I didn't mention successfully earning my doctorate earlier in the year), I cannot hide my excitement that my first author article, "Active and Accurate trans-Translation Requires Distinct Determinants in the C-terminal Tail of SmpB Protein and the mRNA-like Domain of Transfer Messenger RNA (tmRNA)", has been selected for paper of the week.
As a paper of the week (an honor bestowed on less than 5% of all JBC articles, I am told), there is a neat summary of the article on the JBC site. The summary / synopsis piece is entitled "How Two Molecules Keep Ribosomes Moving". Along with this preview, there is also short profile about me.
Unfortunately, reading the actual, finished article requires a subscription to the Journal of Biological Chemistry. A word of caution to interested readers: it is written for an expert scientific audience (as almost all research articles for scientific journals are). However, it is possible to view the earlier, 'online' version of the article; in addition, the JBC capsule provides a bite-sized summary of the work.
The below is copied from the article page at the JBC website. Although I wrote most of it, I claim no copyright. You can find the original text at http://www.jbc.org/content/early/2013/08/28/jbc.M113.503896
Background: tmRNA and small protein B (SmpB) rescue stalled ribosomes through a template switching mechanism.
Results: Changes to the SmpB hinge, SmpB C-terminus, or tmRNA ORF affect ribosome rescue activity and accuracy.
Conclusion: Proper positioning of SmpB and tmRNA make distinct and supplementary contributions to ribosome rescue.
Significance: Template switching requires concerted action of distinct SmpB, tmRNA, and ribosomal determinants.