A recent publication from Dr. Julie Saba et al., (Children’s Hospital Oakland Research Institute, Oakland, California, reference https://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0037218) highlights the role played by the signaling lipid sphingosine-1-phosphate (S1P) in controlling the fate of satellite cells (muscle stem cells) in mdx mice.