Delta and Serrate are redundant Notch ligands required for asymmetric cell divisions within the Drosophila sensory organ lineage

Delta and Serrate are redundant Notch ligands required for asymmetric cell divisions within the Drosophila sensory organ lineage

Howard Hughes Medical Institute and Departments of Physiology and Biochemistry, University of California, San Francisco, California 94143 USA

Abstract

Asymmetric divisions allow a precursor to produce four distinct cells of a Drosophila sensory organ lineage (SOL). Whereas this process requires cell–cell communication via Notch (N) receptor, mitotic recombination that removes the N ligand Delta (Dl) or Serrate (Ser) in the SOL had mild or no effect. Removal of both Dl andSer, however, led to cell fate transformations similar to theN phenotype. Cell fate transformation occurred even when a single SOL cell lost both Dl and Ser. Thus, Dland Ser are redundant in mediating signaling between daughter cells to specify their distinct cell fates.