Encountering MicroRNAs in Cell Fate Signaling

摘要

Organisms must tightly regulate where and when each of their genes is expressed, lest their development goes awry with potentially lethal consequences. The mechanisms that control these important time and place decisions have been of great investigative interest. Hence, it came as a huge surprise that a major level of gene regulation was completely unknown until the recent discovery of a class of small regulatory RNA molecules known as microRNAs. Ever since, we have been racing to understand microRNA function during the development of multicellular animals and plants. On page 1330 in this issue, Yoo and Greenwald describe a direct connection between the miR-61 microRNA and LIN-12/Notch, the cell surface receptor that controls a fundamental and highly conserved signaling pathway. The link marks an important advance in our understanding of the role of microRNAs in developmental processes.