Baculovirus expression construct. Drosophila melanogaster Toll receptor is a 1097-residue-long transmembrane protein with an ectodomain of leucine-rich repeats (28–801 residues), a helical transmembrane region (TM, residues 808–828) and an intracellular domain with a Toll-interleukin-1 receptor signalling domain (TIR domain, residues 857–996). The N-terminal region of the Toll ectodomain Met1–Leu228 is expressed as a chimera with the VLR C-terminal capping structure Asn133–Thr201, a TEV protease cleavage site and the constant fragment of human immunoglobulin G1 for purification (Gangloff et al., 2013). The 24 residue-long consensus LRR sequence is given with X standing for any amino acid, L for Leu and N for Asn. The sequences of Toll and VLR are fused in the middle of the conserved leucine-rich repeat motif of LRR6 at Leu228.