title: Epidermal cells are the primary phagocytes in the fragmentation and clearance of degenerating dendrites in Drosophila.
abstract: During developmental remodeling, neurites destined for pruning often degenerate on-site. Physical injury also induces degeneration of neurites distal to the injury site. Prompt clearance of degenerating neurites is important for maintaining tissue homeostasis and preventing inflammatory responses. Here we show that in both dendrite pruning and dendrite injury of Drosophila sensory neurons, epidermal cells rather than hemocytes are the primary phagocytes in clearing degenerating dendrites. Epidermal cells act via Draper-mediated recognition to facilitate dendrite degeneration and to engulf and degrade degenerating dendrites. Using multiple dendritic membrane markers to trace phagocytosis, we show that two members of the CD36 family, croquemort (crq) and debris buster (dsb), act at distinct stages of phagosome maturation for dendrite clearance. Our finding reveals the physiological importance of coordination between neurons and their surrounding epidermis, for both dendrite fragmentation and clearance.
authors.affiliation: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, Rock Hall, 1550 4 Street, San Francisco, CA 94158, USA.
authors.forename: Chun
authors.initials: C
authors.lastname: Han
authors.affiliation: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, Rock Hall, 1550 4 Street, San Francisco, CA 94158, USA.
authors.forename: Yuanquan
authors.initials: Y
authors.lastname: Song
authors.affiliation: Department of Immunology & Microbial Sciences, The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA92037, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Xiao
authors.affiliation: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, Rock Hall, 1550 4 Street, San Francisco, CA 94158, USA.
authors.forename: Denan
authors.initials: D
authors.lastname: Wang
authors.affiliation: Department of Immunology & Microbial Sciences, The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA92037, USA.
authors.forename: Nathalie C
authors.initials: NC
authors.lastname: Franc
authors.affiliation: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, Rock Hall, 1550 4 Street, San Francisco, CA 94158, USA.
authors.forename: Lily Yeh
authors.initials: LY
authors.lastname: Jan
authors.affiliation: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, Rock Hall, 1550 4 Street, San Francisco, CA 94158, USA.
authors.forename: Yuh-Nung
authors.initials: YN
authors.lastname: Jan
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D018955:CD36 Antigens / Q000378:metabolism; D003712:Dendrites / Q000378:metabolism* / Q000648:ultrastructure; D004330:Drosophila; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D000078404:Epidermal Cells; D004847:Epithelial Cells / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D007814:Larva; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D009154:Mutation / Q000235:genetics; D009410:Nerve Degeneration / Q000473:pathology / Q000503:physiopathology*; D010587:Phagocytosis / Q000502:physiology*; D011679:Pupa; D034622:RNA Interference / Q000502:physiology; D051116:Receptors, Scavenger / Q000235:genetics / Q000378:metabolism; D011984:Sensory Receptor Cells / Q000166:cytology*; D013997:Time Factors
chemical_list: D018955:CD36 Antigens; D029721:Drosophila Proteins; D008164:Luminescent Proteins; D051116:Receptors, Scavenger; C099526:crq protein, Drosophila