Transforming growth factor-betas and related gene products in mosquito vectors of human malaria parasites: signaling architecture for immunological crosstalk.
The participation of a divergent mosquito transforming growth factor-beta (TGF-beta) and mammalian TGF-beta1 in the Anopheles stephensi response to malaria parasite development [Infect. Genet. Evol. 1 (2001) 131-141; Infect. Immun. 71 (2003) 3000-3009] suggests that a network of Anopheles TGF-beta ligands and signaling pathways figure prominently in immune defense of this important vector group. To provide a basis for identifying the roles of these proteins in Anopheles innate immunity, we identified six predicted TGF-beta ligand-encoding genes in the Anopheles gambiae genome, including two expressed, diverged copies of 60A, the first evidence of ligand gene duplication outside of chordates. In addition to five predicted type I and II receptors, we identified three Smad genes in the A. gambiae genome that would be predicted to support both TGF-beta/Activin- and bone morphogenetic protein (BMP)-like signaling. All three Smad genes are expressed in an immunocompetent A. stephensi cell line and in the A. stephensi midgut epithelium, confirming that a conserved signaling architecture is in place to support signaling by divergent exogenous and endogenous TGF-beta superfamily proteins.
Department of Biochemistry, Virginia Tech, 306 Engel Hall, Mail Stop 0308, West Campus Drive, Blacksburg, VA 24061, USA.
Matthew J
MJ
Lieber
Shirley
S
Luckhart
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D009033:Culicidae / Q000235:genetics* / Q000276:immunology; D006801:Humans; D008024:Ligands; D008288:Malaria / Q000276:immunology / Q000635:transmission*; D008969:Molecular Sequence Data; D010802:Phylogeny; D010961:Plasmodium / Q000276:immunology; D016415:Sequence Alignment; D015398:Signal Transduction / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000235:genetics*
D008024:Ligands; D016212:Transforming Growth Factor beta