Post Transcriptional Regulation of gene expression
The messenger RNA (mRNA) is the intermediate molecule that is formed from the DNA that stores the genetic information and before the generation of a protein that execute the genetic information into a function. The existence of this intermediate molecule creates a wide variety of regulation in time, space, amount and the actual function, all of which are named post-transcriptional regulation. The regulators are RNA binding proteins and small RNA molecules which bind the mRNA and regulate which protein isoform will be expressed, where, when and how much. In our lab, we mainly focus on characterizing the post-transcriptional role of microRNAs (miRNAs) in the stem cell niche and their effect on aging.
miRNAs are small non-coding single stranded RNAs that are transcribed from the organism genome very similarly to mRNAs. However, unlike mRNAs they are not translated but rather recognize anti-sense sequence in the single-stranded mRNA to bind and silence its translation.
miRNA silence protein expression: A miRNA regulates its mRNA targets through binding to a small primary recognition sequence of 6-8 nucleotides. These regulatory sequences are located throughout the mRNA but their presence is predominantly in the 3’ untranslated region (3’UTR). The 6 nucleotides seed sequence is located at the 5’ of the miRNA, between nucleotides 2-8. This seed recognizes and base-pair with the anti-sense recognition sequence of the mRNA to inhibit the translation machinery.