Morpholinos for splice modificatio

Morpholinos for splice modification


An extracellular region of Serrate is essential for ligand-induced cis-inhibition of Notch signaling
Robert J. Fleming, Kazuya Hori, Anindya Sen, Gina V. Filloramo, Jillian M. Langer, Robert A. Obar, Spyros Artavanis-Tsakonas, Ayiti C. Maharaj-Best


Cell-to-cell communication via the Notch pathway is mediated between the membrane-bound Notch receptor and either of its canonical membrane-bound ligands Delta or Serrate. Notch ligands mediate receptor transactivation between cells and also mediate receptor cis-inhibition when Notch and ligand are co-expressed on the same cell. We demonstrate in Drosophila that removal of any of the EGF-like repeats (ELRs) 4, 5 or 6 results in a Serrate molecule capable of transactivating Notch but exhibiting little or no Notch cis-inhibition capacity. These forms of Serrate require Epsin (Liquid facets) to transduce a signal, suggesting that ELR 4-6-deficient ligands still require endocytosis for Notch activation. We also demonstrate that ELRs 4-6 are responsible for the dominant-negative effects of Serrate ligand forms that lack the intracellular domain and are therefore incapable of endocytosis in the ligand-expressing cell. We find that ELRs 4-6 of Serrate are conserved across species but do not appear to be conserved in Delta homologs.

  • Accepted February 28, 2013.
View Full Text