Week In Science

Ambion's miRNA Resource is a good place to familiarize oneself with microRNA. MicroRNA has become increasingly important to researchers as its impact on cellular function has become known.

A press release entitled Mechanism of microRNAs deciphered reveals the role of microRNA in controlling gene expression and in regulating vital cellular functions like cell division and the development of cells. According to the cited study, microRNA is able to prevent protein synthesis by blocking the translation process that makes synthesis possible. The specific mechanism employed entails microRNA binding to mRNA; a type of RNA that carries the transcribed message from DNA to cellular constructs involved in translating the message. The binding may prevent translation by making mRNA (messenger RNA) inaccesible to ribosomes. Ribosomes are the "protein factory" sites where synthesis occurs.

The newly gained information could lead to breakthroughs in disease and cancer research. Advances in drug treatment could also follow. As the release notes microRNAs are involved in controlling more than 30% of our genes.

A Nature,1 article also deals with another significant discovery related to microRNA. This has to do with microRNA being found in green algae. This is significant because a prevailing view had been that multi-cellular organisms evolved along with the capacity for the regulatory role played by microRNA. We now know that microRNA complexity extends to unicellular organisms. Further information about the exact roles played by microRNA in green algae will await further research efforts. So too will speculation about the origin of microRNA functions.

1Lucy Odling-Smee, “Complex set of RNAs found in simple green algae: Single-celled organisms aren’t as basic as they seem,” Nature 447, 518 (31 May 2007) | doi:10.1038/447518b.