The proper removal of superfluous neurons through apoptosis and subsequent phagocytosis is essential for normal development of the central nervous system (CNS). During Drosophila embryogenesis, a large number of apoptotic neurons are efficiently engulfed and degraded by phagocytic glia. Here we demonstrate that glial proficiency to phagocytose relies on expression of phagocytic receptors for apoptotic cells, SIMU and DRPR. Moreover, we reveal that the phagocytic ability of embryonic glia is established as part of a developmental program responsible for glial cell fate determination and is not triggered by apoptosis per se. Explicitly, we provide evidence for a critical role of the major regulators of glial identity, gcm and repo, in controlling glial phagocytic function through regulation of SIMU and DRPR specific expression. Taken together, our study uncovers molecular mechanisms essential for establishment of embryonic glia as primary phagocytes during CNS development.
Bibliographical noteFunding Information:
We would like to thank B. Jones, H. Steller, E. Arama, M. Freeman, N. Franc, O. Schuldiner, Hybridoma bank and the Bloomington Stock Center for generously providing fly strains and antibodies. We thank A. Salzberg, Z. Paroush and T. Schultheiss for comments on the manuscript and the Kurant laboratory members for constructive criticism and support. We also thank E. Suss-Toby and L. Liba at the Interdepartmental Bioimaging facility for excellent technical support. We gratefully acknowledge financial support from Israel Science Foundation (Grant no 427/11 ).
© 2014 Elsevier Inc.
ASJC Scopus subject areas
- Molecular Biology
- Developmental Biology
- Cell Biology