The segmental pattern of the vertebrate body is established via the periodic formation of somites from the presomitic mesoderm (PSM). This periodical process is controlled by the cyclic and synchronized activation of Notch signaling in the PSM. Protein O-fucosyltransferase1 (Pofut1). which transfers O-fucose to the EGF domains of the Notch1 receptor. https://www.roneverhart.com/Sigma-Phi-Lambda-Lil-Big-Sister-Tee-Discontinued/