Open AccessProtein phosphatase 4 coordinates glial membrane recruitment and phagocytic clearance of degenerating axons in Drosophila
Author(s) -
Lilly Winfree,
Sean D. Speese,
Mary A. Logan
Publication year - 2017
Publication title -
cell death and disease
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.482
H-Index - 111
ISSN - 2041-4889
DOI - 10.1038/cddis.2017.40
Subject(s) - microbiology and biotechnology , biology , glial scar , microglia , neuroglia , phosphatase , rac1 , neuroscience , signal transduction , astrocyte , phosphorylation , central nervous system , immunology , inflammation
Neuronal damage induced by injury, stroke, or neurodegenerative disease elicits swift immune responses from glial cells, including altered gene expression, directed migration to injury sites, and glial clearance of damaged neurons through phagocytic engulfment. Collectively, these responses hinder further cellular damage, but the mechanisms that underlie these important protective glial reactions are still unclear. Here, we show that the evolutionarily conserved trimeric protein phosphatase 4 (PP4) serine/threonine phosphatase complex is a novel set of factors required for proper glial responses to nerve injury in the adult Drosophila brain. Glial-specific knockdown of PP4 results in reduced recruitment of glia to severed axons and delayed glial clearance of degenerating axonal debris. We show that PP4 functions downstream of the the glial engulfment receptor Draper to drive glial morphogenesis through the guanine nucleotide exchange factor SOS and the Rho GTPase Rac1, revealing that PP4 molecularly couples Draper to Rac1-mediated cytoskeletal remodeling to ensure glial infiltration of injury sites and timely removal of damaged neurons from the CNS.