Small RNAs and RNA interference
RNA interference (RNAi) and related pathways engage small regulatory RNAs (small RNAs, ~20-30 nucleotides) to control the expression of our genes to ensure that their protein products are produced at the right levels and at the right times during development and in response to internal and external cues. Small RNAs fall into three broad categories - microRNAs (miRNAs), piwi-interacting RNAs (piRNAs), and small-interfering RNAs (siRNAs). The various classes of small RNAs affect gene expression through a variety of molecular mechanisms. In some instances, small RNAs guide modifications to DNA that likely prevent it from expressing its gene products. In other instances, small RNAs cause the degradation of the messenger RNAs that encode for proteins. Small RNAs are incredibly adaptable and together with their protein cofactors they have proliferated and diversified extensively so as to control a wide range of biological processes. Many features of small RNA pathways are conserved between animals as distantly related as nematodes and humans and even between plants and animals. Our research focuses on understanding these important regulatory pathways and how they affect gene expression and development. We also study how small RNAs affect various disease states and susceptibility to drugs and toxins. Although considerable progress has been made in our understanding of small RNA pathways in the past 20 years, there are still many exciting discoveries to be made!