The spätzles and Toll-like receptors of H. armigera. (A) Phylogenetic analysis of spätzle homologs. The amino acid sequences of 6 H. armigera (Ha), 4 T. castaneum (Tc), 6 D. melanogaster (Dm), 3 B. mori (Bm), 1 M. sexta (Ms), 5 A. gambiae (Ag), and 2 A. mellifera (Am) spätzles are compared. The red dots at nodes denote bootstrap values greater than 800 from 1,000 trials. Scale bar, 0.1 substitutions per site. (B) Phylogenetic analysis of Toll-like receptors from seven insect species. The amino acid sequences of 11 Ha, 9 Tc, 9 Dm, 7 Bm, 2 Aa, 6 Ag and 3 Am Toll-like receptors are examined. Scale bar, 0.1 substitutions per site. (C) Schematic representations of the domain structure of H. armigera Tolls. Lengths of the amino acid sequences are indicated.