A paper from Itoh et al. has stuck with me since its publication date 8 years ago for many reasons, but primarily because it stretched my mind and pleased my eye. The major conclusion of the paper—that bomb-mediated ubiquitination of promotes its endocytosis, thereby activating Notch signaling in an adjacent cell—was an important advance in the fields of ubiquitin-mediated regulation, Delta-Notch activated signaling, and neuronal development. For these reasons the title and abstract caught my attention. However, this manuscript was a challenging read for a life-long yeast cell biologist. I had heard talks over the years from my developmental biology colleagues, but I wasn't used to looking carefully at zebrafish embryos. I had also never rigorously thought through the experiments that would be needed to test whether a signal was acting cell autonomously in vivo. The paper therefore took time, but it was well worth it: the data are spectacular, both in clarity and aesthetics, and the conclusions are significant. A paper with a protein named bomb, magenta and green fluorescent micrographs, and a description of a new ubiquitin ligase has everything it takes to make my day. This PaperPick relates to Mind Bomb Is a Ubiquitin Ligase that Is Essential for Efficient Activation of Notch Signaling by Delta by M. Itoh, C.-H. Kim, G. Palardy, T. Oda, Y.-J. Jiang, D. Maust, S.-Y. Yeo, K. Lorick, G.J. Wright, L. Ariza-McNaughton, A.M. Weissman, J. Lewis, S.C. Chandrasekharappa, and A.B. Chitnis, published in January 2003. Video Abstract The first author of the original Developmental Cell paper, Dr. Motoyuki Itoh, introduces the mind bomb mutation, the work he did on it in Dr. Ajay Chitnis's laboratory, and some unanswered questions surrounding Notch ligand ubiquitination that persist to this day.