In terms of methodology, this is a very interesting paper. The results, on the other hand, can revolutionize our way of thinking regarding the ribosomes and the translation process. The authors employ the laser trap technology, formerly developed to measure the molecular forces (piconewtons) and displacements (nanometers) generated by a single myosin molecular motor as it interacts with a single actin filament, to follow a single ribosome translating an mRNA hairpin. Below, you can see their experimental set-up.
According to their results, translation does not occur continuously as we thought so. When the ribosome starts translocating, it opens up the hairpin, thus increasing the distance between the two beads which is measurable by the laser trap. As you see in the figure below, the ribosome goes through a translocation-pause cycles (shown with arrows in the top panel).
This is a really important change in how we look at translation. For example, each of these pause times (that differ in length quite drastically) can act as foci of post-transcriptional regulation.
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