RNA Ecology
A paper came out in PNAS two days ago on a new ribozyme (that is, an “RNA enzyme”) that can (sort of) self-replicate and evolve!
Well, ok, it’s a bit more complicated than that. There is a certain kind of ribozyme that can attach itself to another RNA fragment of a particular sequence. The authors made this ribozyme into a version that attaches itself to a promoter, which allows its sequence to be read back and converted into DNA by reverse transcriptase. That DNA can then be read and converted back to RNA by an RNA polymerase, and the cycle continues. So, in a sense, replication (and thus evolution). Here’s a picture of the process from the paper (sorry about the small text…it’s the only way the figure will fit):
Now, this isn’t exactly new. Someone else has constructed a ribozyme that can do this. But now, there are two very different ribozymes that do similar things and replicate, so the coolest part is that now you can do “molecular ecology,” where the two RNA molecules compete with each other for resources! It’s a whole new kind of experimental evolution!
