In a paper published online in advance this week, investigators at Stanford University School of Medicine and elsewhere show that miR-489 is "highly expressed in quiescent satellite cells and is quickly downregulated during satellite-cell activation." Further, the team found that miR-489 "functions as a regulator of satellite-cell quiescence, as it post-transcriptionally suppresses the oncogene Dek, the protein product of which localizes to the more differentiated daughter cell during asymme