Fig. 6.

IpLITR2 contains Ig domains related to both FcRs/FCRLs and CHIRs. a Amino acid alignment of IpLITR2 D1 and D2 sequences with representative mammalian FcRs and FCRLs. Accession numbers are as in Fig. 5. Gray shading: residues similar/identical to IpLITR2. Boxed residues: contacts for Ig Fc in huFcεRI. Black and gray arrows represent the predicted β-strands for IpLITR2 and huFcεRI, respectively. Hatched boxes indicate conserved cyteines and dashes represent gaps. b Phylogenetic analysis of IpLITR2 D1 and D3 sequences (gray shaded) compared with representative mammalian FcR sequences (as in Fig. 5) and D1 sequences of representative CHIRs. The accession numbers for the various Ig domain sequences used are: CHIRB2 (XP_422905), CHIRB1 (CAH55757), CHIRAB2 (CAG33733), CHIRA2 (CAG33731), CHIRB5 (AJ879908), CHIR A1 (AF306851), CHIRB4 (XP_428342), CHIRB6 (CAI53861), and CHIRAB3 (AJ879909). NJ trees with pairwise gap deletions were drawn using MEGA v3.0 (Kumar et al. 2001) with 10,000 bootstrap replications, and bootstrap values >50% are shown. Branch lengths were measured in terms of amino acid substitutions, and scale bars are shown below the trees. c Alignment of IpLITR2 D3 and CHIR D1. Gray shading indicates residues that are similar/identical to IpLITR2, black and gray arrows represent predicted β-strands for IpLITR2 and CHIRA2, respectively; “dotted” lines indicate predicted helices and hatched boxes indicate conserved cyteines. Gaps in alignment are indicated by dashes