生物
先天免疫系统
预言酚氧化酶
模式识别受体
信号转导
小虾
细胞生物学
受体
清道夫受体
类胡萝卜素
微生物学
抗菌肽
脂多糖
肽聚糖
细胞外
生物化学
抗菌剂
免疫学
酶
生态学
胆固醇
脂蛋白
作者
Xiaoping Shi,Ming-Chong Yang,Xin-Le Kang,Y. Li,Pan-Pan Hong,Xiao-Fan Zhao,Gerardo R. Vasta,Jin-Xing Wang
标识
DOI:10.1073/pnas.2216574120
摘要
The immune deficiency (IMD) pathway is critical for elevating host immunity in both insects and crustaceans. The IMD pathway activation in insects is mediated by peptidoglycan recognition proteins, which do not exist in crustaceans, suggesting a previously unidentified mechanism involved in crustacean IMD pathway activation. In this study, we identified a Marsupenaeus japonicus B class type III scavenger receptor, SRB2, as a receptor for activation of the IMD pathway. SRB2 is up-regulated upon bacterial challenge, while its depletion exacerbates bacterial proliferation and shrimp mortality via abolishing the expression of antimicrobial peptides. The extracellular domain of SRB2 recognizes bacterial lipopolysaccharide (LPS), while its C-terminal intracellular region containing a cryptic RHIM-like motif interacts with IMD, and activates the pathway by promoting nuclear translocation of RELISH. Overexpressing shrimp SRB2 in Drosophila melanogaster S2 cells potentiates LPS-induced IMD pathway activation and diptericin expression. These results unveil a previously unrecognized SRB2-IMD axis responsible for antimicrobial peptide induction and restriction of bacterial infection in crustaceans and provide evidence of biological diversity of IMD signaling in animals. A better understanding of the innate immunity of crustaceans will permit the optimization of prevention and treatment strategies against the arising shrimp diseases.
科研通智能强力驱动
Strongly Powered by AbleSci AI