Maintenance of glia in the optic lamina is mediated by EGFR signaling by photoreceptors in adult Drosophila

PLoS Genet. 2015 Apr 24;11(4):e1005187. doi: 10.1371/journal.pgen.1005187. eCollection 2015 Apr.

Abstract

The late onset of neurodegeneration in humans indicates that the survival and function of cells in the nervous system must be maintained throughout adulthood. In the optic lamina of the adult Drosophila, the photoreceptor axons are surrounded by multiple types of glia. We demonstrated that the adult photoreceptors actively contribute to glia maintenance in their target field within the optic lamina. This effect is dependent on the epidermal growth factor receptor (EGFR) ligands produced by the R1-6 photoreceptors and transported to the optic lamina to act on EGFR in the lamina glia. EGFR signaling is necessary and sufficient to act in a cell-autonomous manner in the lamina glia. Our results suggest that EGFR signaling is required for the trafficking of the autophagosome/endosome to the lysosome. The loss of EGFR signaling results in cell degeneration most likely because of the accumulation of autophagosomes. Our findings provide in vivo evidence for the role of adult neurons in the maintenance of glia and a novel role for EGFR signaling in the autophagic flux.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Axons / metabolism
  • Cell Differentiation / genetics*
  • Drosophila / growth & development
  • Drosophila / metabolism
  • ErbB Receptors / genetics*
  • Humans
  • Neuroglia / metabolism*
  • Neurons / metabolism
  • Photoreceptor Cells, Invertebrate / metabolism
  • Retina / metabolism*
  • Retina / pathology
  • Signal Transduction
  • Spinal Cord Dorsal Horn / growth & development
  • Spinal Cord Dorsal Horn / metabolism

Substances

  • ErbB Receptors

Grants and funding

YHS (NSC 96-2321-B-001-002, NSC 97-2321-B-001-002, NSC 98-2321-B-001-034, NSC 99-2321-B-001-016, NSC 100-2321-B-001-012, NSC 101-2321-B-001-004, NSC 102-2321-B-001-002) from the National Science Council of the Republic of China (http://www.most.gov.tw/mp.aspx?mp=7). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.