Monday, February 12, 2007

The many faces of microRNAs   posted by rosko @ 2/12/2007 07:20:00 PM

First of all I would like to invite you all to come and check out my new blog, Science, Theory, and Liberty, at Unlike here at GNXP, my week of science is just starting, since I haven't had much of a chance to post to blogs lately. Since I won't have access to a computer from Wednesday evening through Saturday night, some of the posting may actually last into early next week. If some people would actually leave some comments on some of my posts, that would be nice.

Now to the content...

As the biological community has become more appreciative of the many roles played by non-coding RNA in the cell, there have been a few key types of RNA for which new functions are being discovered at a rapid pace. One of these is the class of microRNAs, which are short pieces of RNA that fold into stem-loop structures and which are known to regulate gene expression post-transcriptionally by targeting mRNAs.

I was first introduced to this class of RNAs when I worked for a semester on a project that was trying to characterize their mechanism of action. Since then, I have witnessed many discoveries regarding their effects, and I will briefly mention some of the latest ones here:

-Marshall et. al. report on how microRNAs encoded by the Kaposi sarcoma-associated herpesvirus are highly conserved, suggesting that they contribute to the pathogenicity of the virus.
-Linsley et. al. have found that one particular family of microRNAs appears to be involved in blocking cell cycle progression out of the G0 and G1 phases.
-Flynt et. al. discovered that a particular microRNA in zebrafish regulates genes in the well-known Hedgehog developmental signaling pathway, and is involvied in the differentiation of muscle cells
-Presutti et. al. review the types of non-coding RNAs, including microRNAs, present in neurons and some findings regarding their roles in growth and synaptic plasticity.
-In probably the most directly applicable of these studies, Lee et. al. identified a microRNA signature in pancreatic cancer cells.