Eater, a Transmembrane Protein Mediating Phagocytosis of Bacterial Pathogens in Drosophila

• Published in: Cell Vol. 123; no. 2; pp. 335 - 346
• Main Authors: Kocks, Christine, Cho, Ju Hyun, Nehme, Nadine, Ulvila, Johanna, Pearson, Alan M., Meister, Marie, Strom, Charles, Conto, Stephanie L., Hetru, Charles, Stuart, Lynda M., Stehle, Thilo, Hoffmann, Jules A., Reichhart, Jean-Marc, Ferrandon, Dominique, Rämet, Mika, Ezekowitz, R. Alan B.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 21.10.2005
• Subjects: Amino Acid Motifs; Amino Acid Sequence; Animals; Bacteria; Bacterial Infections - prevention & control; Drosophila; Drosophila - cytology; Drosophila - embryology; Drosophila - genetics; Drosophila - microbiology; Drosophila Proteins - genetics; Drosophila Proteins - metabolism; Drosophila Proteins - physiology; Embryo, Nonmammalian; Escherichia coli - pathogenicity; Flow Cytometry; Frameshift Mutation; Genes, Insect; Histidine - chemistry; In Situ Hybridization; Insect Proteins - chemistry; Insect Proteins - genetics; Insect Proteins - metabolism; Insect Proteins - physiology; Macrophages - metabolism; Membrane Proteins - chemistry; Membrane Proteins - genetics; Membrane Proteins - metabolism; Membrane Proteins - physiology; Molecular Sequence Data; Open Reading Frames; Phagocytosis; Receptors, Cell Surface - genetics; Receptors, Cell Surface - metabolism; Receptors, Cell Surface - physiology; RNA Interference; RNA, Messenger - metabolism; Sequence Homology, Amino Acid; Serratia marcescens - pathogenicity
• ISSN: 0092-8674; 1097-4172
• DOI: 10.1016/j.cell.2005.08.034

Phagocytosis is a complex, evolutionarily conserved process that plays a central role in host defense against infection. We have identified a predicted transmembrane protein, Eater, which is involved in phagocytosis in Drosophila. Transcriptional silencing of the eater gene in a macrophage cell line led to a significant reduction in the binding and internalization of bacteria. Moreover, the N terminus of the Eater protein mediated direct microbial binding which could be inhibited with scavenger receptor ligands, acetylated, and oxidized low-density lipoprotein. In vivo, eater expression was restricted to blood cells. Flies lacking the eater gene displayed normal responses in NF-κB-like Toll and IMD signaling pathways but showed impaired phagocytosis and decreased survival after bacterial infection. Our results suggest that Eater is a major phagocytic receptor for a broad range of bacterial pathogens in Drosophila and provide a powerful model to address the role of phagocytosis in vivo.