Open AccessScavenger Receptor C Mediates Phagocytosis of White Spot Syndrome Virus and Restricts Virus Proliferation in Shrimp
Author(s) -
Ming-Chong Yang,
Xiaoping Shi,
Huiting Yang,
Jiejie Sun,
Ling Xu,
Xianwei Wang,
XiaoFan Zhao,
Jinxing Wang
Publication year - 2016
Publication title -
plos pathogens
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.719
H-Index - 206
eISSN - 1553-7374
pISSN - 1553-7366
DOI - 10.1371/journal.ppat.1006127
Subject(s) - scavenger receptor , white spot syndrome , internalization , biology , shrimp , phagocytosis , microbiology and biotechnology , endocytosis , receptor , virus , virology , biochemistry , lipoprotein , cholesterol , fishery
Scavenger receptors are an important class of pattern recognition receptors that play several important roles in host defense against pathogens. The class C scavenger receptors (SRCs) have only been identified in a few invertebrates, and their role in the immune response against viruses is seldom studied. In this study, we firstly identified an SRC from kuruma shrimp, Marsupenaeus japonicus , designated Mj SRC, which was significantly upregulated after white spot syndrome virus (WSSV) challenge at the mRNA and protein levels in hemocytes. The quantity of WSSV increased in shrimp after knockdown of Mj SRC, compared with the controls. Furthermore, overexpression of Mj SRC led to enhanced WSSV elimination via phagocytosis by hemocytes. Pull-down and co-immunoprecipitation assays demonstrated the interaction between Mj SRC and the WSSV envelope protein. Electron microscopy observation indicated that the colloidal gold-labeled extracellular domain of Mj SRC was located on the outer surface of WSSV. Mj SRC formed a trimer and was internalized into the cytoplasm after WSSV challenge, and the internalization was strongly inhibited after knockdown of Mj β-arrestin2. Further studies found that Mj β-arrestin2 interacted with the intracellular domain of Mj SRC and induced the internalization of WSSV in a clathrin-dependent manner. WSSV were co-localized with lysosomes in hemocytes and the WSSV quantity in shrimp increased after injection of lysosome inhibitor, chloroquine. Collectively, this study demonstrated that Mj SRC recognized WSSV via its extracellular domain and invoked hemocyte phagocytosis to restrict WSSV systemic infection. This is the first study to report an SRC as a pattern recognition receptor promoting phagocytosis of a virus.