Abstract:
Diverse neuronal cell types arise from the lateral neuroblast in the antennal lobe of Drosophila. The authors show that loss of Notch function from the entire lineage during development leads to an absence of local interneurons (LNs) with a concomitant increase in the number of projection neurons (PNs). The presence of the intracellular domain of Notch was observed within the nucleus of newly born neurons within the neuroblast lineage. This leads to the suggestion that Notch acts in a binary fate decision to determine formation of LNs and PNs, resulting in two distinct hemilineages from the single neuroblast. The observation of nuclear Notch in several neuroblast lineages leads us to speculate that this mechanism is widespread during the developing Drosophila brain.
ACKNOWLEDGMENTS
We thank Kei Ito, Reinhard Stocker, Tzumin Lee, Liquin Luo, Gero Meisenbock, and the Bloomington Stock Centre for many of the fly stocks and Juan Botas and Developmental Studies Hybridoma Bank for antibodies. We acknowledge K. VijayRaghavan and Sonia Sen for discussions, and Tripti Gupta for technical help. This work was supported by grants from TIFR and the Indo-Swiss Joint Research Program. We thank the Department of Science and Technology, Government of India—Centre for Nanotechnology (No. SR/S5/NM-36/2005), the Central Imaging and Flow Cytometry Facility, and the NCBS Olympus MicroImaging Centre, for imaging facilities.
Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.