Constitutive expression of a complement-like protein in Toll and JAK gain-of-function mutants of Drosophila

M. Lagueux (1) , E. Perrodou (1) , E. Levashina (1) , Maria Capovilla (1) , J. Hoffmann (1)

1 IBMC - Institut de biologie moléculaire et cellulaire

We show that Drosophila expresses four genes encoding proteins with significant similarities with the thiolester-containing proteins of the complement C3/alpha(2)-macroglobulin superfamily. The genes are transcribed at a low level during all stages of development, and their expression is markedly up-regulated after an immune challenge. For one of these genes, which is predominantly expressed in the larval fat body, we observe a constitutive expression in gain-of-function mutants of the Janus kinase (JAK) hop and a reduced inducibility in loss-of-function hop mutants. We also observe a constitutive expression in gain-of-function Toll mutants. We discuss the possible roles of these novel complement-like proteins in the Drosophila host defense.

Domaines: Immunité innée; Génétique animale; Biochimie [q-bio.BM]

M. Lagueux, E. Perrodou, E. Levashina, Maria Capovilla, J. Hoffmann. Constitutive expression of a complement-like protein in Toll and JAK gain-of-function mutants of Drosophila. Proceedings of the National Academy of Sciences of the United States of America, 2000, 97 (21), pp.11427-11432. ⟨10.1073/pnas.97.21.11427⟩. ⟨hal-02333168⟩