Structural properties of NLRR4. (a) The deduced amino acid sequences of mouse (upper) and human (lower) NLRR4. The putative signal peptide is underlined, and the transmembrane region is boxed. Identical amino acid residues are indicated by dots, and the leucine-rich repeats (LRRs) and fibronectin III (FN III) domains are indicated by the arrows underneath the sequences. (b) Structures of the NLRR family members. All members are type I transmembrane proteins with leucine-rich repeats and fibronectin III motifs in their extracellular region. SP, signal peptide; AF, amino-flanking region; CF, carboxy-flanking region; TM, transmembrane.