As any celebrity can tell you, lighting conditions can make a big difference. A new article in Cell shows that lighting can effect much more than just whether or not a star looks good on the cover of People Magazine, it also plays a part in regulating miRNA expression in the retina.
A group from the Friedrich Miescher Institute for Biomedical Research in Basel, Switzerland studied miRNA levels in the retinal neurons of mice. The team profiled retinal RNAs from light-adapted (LA) or dark-adapted (DA) mice using Exiquon’s miRCURY LNATM miRNA Arrays, as well as next-gen sequencing, and found a set of miRNAs whose expression levels changed depending on light exposure including the miR-183/96/182 cluster, miR-204 and miR-211. Further follow up experiments revealed even more enlightening facts:
- The miRNAs studied were up-regulated in LA mice (resulting from increased transcription), and down-regulated in DA mice (caused by faster miRNA degradation), and were not related to circadian rhythms.
- The miR-183/96/182 cluster was shown to target Slc1a1, a neuronal glutamate transporter used by photoreceptors. They also found glutamate stimulation to trigger miRNA decay.
- miRNA turnover is much faster in retinal neurons than other cell types (they found this to be a general feature of neurons) and seems to be correlated with neuronal activity.
The Swiss scientists provided some eye-opening initial steps in deciphering miRNA behavior in neurons.
Get a good look at all of the illuminating details in Cell, May 2010.