At EpiGenie, we do our best to keep up with the latest research trends in the epigenetics scene so we couldn’t help but notice that lately, the Polycomb (PcG) and Trithorax (TrxG) proteins are grabbing more headlines than Octa-Mom. Deservingly so, when you consider the critical role these developmental switchboards play in maintaining expression patterns of hundreds of key genes involved in cell fate.
But like any hot area in the field, things change rapidly so we snatched up this review in RNA Biology, that has a little something for all epigenetic interests, to catch up on the hype. The authors do a nice job at quickly summarizing some mechanistic highlights of PcG and TrxG proteins in development before diving into the potential roles that non-coding RNA (big and small) might play in the recruitment and regulation of both PcG and and TrxG proteins. How’s that for variety?
Polycomb and Trithorax proteins work their regulatory mojo by binding to Polycomb/Trithorax Response Elements (PRE/TREs) in DNA and influencing chromatin structure, but recent evidence also suggests:
- PRE/TREs can be transcribed into long non-coding RNAs.
- PcG and TrxG also bind RNA.
- RNA interactions target PcG/TrxG to specific sites, modulating gene expression.
Given the diverse interactions with these proteins have with DNA, chromatin complexes and non-coding RNAs, it’s no surprise that PcGs and TrxGs are getting more attention than William Shatner at a Star Trek convention. Despite the exciting data though, the authors were quick to point that there are more exceptions than rules at this stage and many of molecular mechanisms have yet to be defined. Add in the various organisms and approaches that have been used, and deciphering what it all means might seem like reading Sanskrit.
In any case, the duo gives a thorough idea of what’s been done, and what’s next while injecting a healthy dose of non-coding RNAs into the regulatory mix. Catch up on all the details at RNA Biology, April 2009