title: Mosquito C-type lectins maintain gut microbiome homeostasis.
abstract: The long-term evolutionary interaction between the host immune system and symbiotic bacteria determines their cooperative rather than antagonistic relationship. It is known that commensal bacteria have evolved a number of mechanisms to manipulate the mammalian host immune system and maintain homeostasis. However, the strategies employed by the microbiome to overcome host immune responses in invertebrates still remain to be understood. Here, we report that the gut microbiome in mosquitoes utilizes C-type lectins (mosGCTLs) to evade the bactericidal capacity of antimicrobial peptides (AMPs).Aedes aegyptimosGCTLs facilitate colonization by multiple bacterial strains. Furthermore, maintenance of the gut microbial flora relies on the expression of mosGCTLs inA. aegypti. Silencing the orthologues ofmosGCTLin another major mosquito vector (Culex pipiens pallens) also impairs the survival of gut commensal bacteria. The gut microbiome stimulates the expression of mosGCTLs, which coat the bacterial surface and counteract AMP activity. Our study describes a mechanism by which the insect symbiotic microbiome offsets gut immunity to achieve homeostasis.
authors.affiliation: Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Tsinghua University, Beijing, 100084, China.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Pang
authors.affiliation: Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Tsinghua University, Beijing, 100084, China.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Xiao
authors.affiliation: Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Tsinghua University, Beijing, 100084, China; School of Life Science, Tsinghua University, Beijing, 100084, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Tsinghua University, Beijing, 100084, China; School of Life Science, Tsinghua University, Beijing, 100084, China.
authors.forename: Rudian
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Tsinghua University, Beijing, 100084, China.
authors.forename: Jianying
authors.initials: J
authors.lastname: Liu
authors.affiliation: Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Tsinghua University, Beijing, 100084, China; State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, China CDC, Beijing, 102206, China.
authors.forename: Qiyong
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, 10595, USA.
authors.forename: Penghua
authors.initials: P
authors.lastname: Wang
authors.affiliation: Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Tsinghua University, Beijing, 100084, China.
authors.forename: Gong
authors.initials: G
authors.lastname: Cheng