%0 Journal Article %T The CLIP-Domain Serine Protease Homolog SPCLIP1 Regulates Complement Recruitment to Microbial Surfaces in the Malaria Mosquito Anopheles gambiae %A Michael Povelones equal contributor %A Lavanya Bhagavatula equal contributor %A Hassan Yassine equal contributor %A Lee Aun Tan %A Leanna M. Upton %A Mike A. Osta %A George K. Christophides %J PLOS Pathogens %D 2013 %I Public Library of Science (PLoS) %R 10.1371/journal.ppat.1003623 %X The complement C3-like protein TEP1 of the mosquito Anopheles gambiae is required for defense against malaria parasites and bacteria. Two forms of TEP1 are present in the mosquito hemolymph, the full-length TEP1-F and the proteolytically processed TEP1cut that is part of a complex including the leucine-rich repeat proteins LRIM1 and APL1C. Here we show that the non-catalytic serine protease SPCLIP1 is a key regulator of the complement-like pathway. SPCLIP1 is required for accumulation of TEP1 on microbial surfaces, a reaction that leads to lysis of malaria parasites or triggers activation of a cascade culminating with melanization of malaria parasites and bacteria. We also demonstrate that the two forms of TEP1 have distinct roles in the complement-like pathway and provide the first evidence for a complement convertase-like cascade in insects analogous to that in vertebrates. Our findings establish that core principles of complement activation are conserved throughout the evolution of animals. %U http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1003623