Domain organization of NACHT, HET-s/LopB, and HET domain proteins. Each shape indicates a specific conserved domain. Fused domains that form a single polypeptide chain are connected by a horizontal line. Aspergilli proteins are located in the area with the yellow background. Ank, Ankyrin domain; CARD, caspase recruitment domain; CC, coiled coil domain; HET, HET domain; HET-s/LopB, new domain found in HET-s and LopB proteins; LRR, leucine-rich repeat; NACHT, NACHT domain; NB-ARC, NB-ARC domain; Pfs, nucleoside phosphorylase domain; SesB/LipA, SesB/LipA domain, found in putative serine esterases and in signaling protein SesB from Nectria haematococca; TIR, toll-interleukin receptor domain, TPR, tetratricopeptide repeat; WD, WD40 domain, found in eukaryotic proteins with various functions including adaptor/regulatory modules in signal transduction; typically contains the WD dipeptide at its C-terminus and is 40 residues long. Figure is not drawn to scale.