Ticks are important ectoparasites and vectors of multiple human and animal diseases. The obligatory hemophagy of ticks provides a formidable route for parasite transmission from one host to another. Parasite survival inside the tick relies on the ability of a pathogen to escape or inhibit tick immune defenses, but the molecular interactions between the tick and its pathogens remain poorly understood. Here we report that tick genomes are unique in that they contain all known classes of the α(2)-macroglobulin family (α(2)M-F) proteins: α(2)-macroglobulin pan-protease inhibitors, C3 complement components, and insect thioester-containing and macroglobulin-related proteins. By using RNA interference-mediated gene silencing in the hard tick Ixodes ricinus we demonstrated the central role of a C3-like molecule in the phagocytosis of bacteria and revealed nonredundant functions for α(2)M-F proteins. Assessment of α(2)M-F functions in a single organism should significantly contribute to the general knowledge on the evolution and function of the complement system. Importantly, understanding the tick immune mechanisms should provide new concepts for efficient transmission blocking of tick-borne diseases.

• MeSH
• alfa-makroglobuliny genetika   MeSH
• Chryseobacterium imunologie   patogenita   MeSH
• fagocytóza genetika   MeSH
• genom imunologie   MeSH
• genomika MeSH
• hemocyty imunologie   metabolismus   mikrobiologie   patologie   MeSH
• hmyzí proteiny genetika   metabolismus   MeSH
• infekce bakteriemi čeledi Flavobacteriaceae genetika   imunologie   MeSH
• komplement C3 genetika   metabolismus   MeSH
• kultivované buňky MeSH
• lidé MeSH
• malá interferující RNA genetika   MeSH
• molekulární evoluce MeSH
• sekvenční analýza DNA MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH