Cell number plasticity drives organismal growth, and is coupled in the CNS to the emergence of neural circuits, ensuring appropriate function. In mammals, neurotrophins promote cell survival via Trk and p75\(^{NTR}\) receptors or induce cell death via p75\(^{NTR}\) and Sortilin. In \(Drosophila\), DNTs bind Toll receptors promoting cell survival, but whether they regulate cell death within the CNS remains unknown. I show Toll receptors have distinct and overlapping spatial and temporal expression and functions. Driving RNAi knockdown and overexpression of each Toll, I show that different Toll receptors are required in glia for adult locomotion; in neurons for the regulation of VNC size; and to induce cell survival or death in distinct contexts. I focused on the signalling mechanisms downstream of Toll-6. My data show DNT-Toll-6 signalling switches between promoting cell survival or death via NFkB, ERK, or JNK signalling. These outcomes depend on the cleavage state of the DNT, time and available downstream adaptors. Toll-6 induces cell survival via MyD88 and cell death via dSarm, and these alternative outcomes depend on Weckle. Altogether, my data contribute to showing that the Toll receptors, DNTs and downstream signalling adaptors constitute a novel mechanism of cell number plasticity within the CNS.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:715506 |
| Date | January 2017 |
| Creators | Anthoney, Niki Cathryn |
| Publisher | University of Birmingham |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://etheses.bham.ac.uk//id/eprint/7343/ |
Page generated in 0.002 seconds