Amino acid sequence homology among IRTA genes and FcγR1 varies by domain.

(A) Extracellular and transmembrane regions. Sequences were aligned using the Clustal 1.8 program46 and formatted by the Boxshade server47 with minor manual readjustments. Residues identical to the consensus (50% or more of sequences) at each position are shown in red. The hydrophobic putative membrane-spanning sequence is underlined. The charged amino acid in the IRTA5 transmembrane region is highlighted in green. (B) Alignment of the cytoplasmic domains of IRTAs 1 through 5. The ITIM consensus sequences are shown below the possible ITIM positions of the IRTA proteins. ITIMs are boxed and bold, ITIM-like sequences are boxed and italicized. ITAM-like sequences are underlined. X denotes any amino acid. Tyrosine residues are colored red. Positions corresponding to exon junctions are marked by arrows.