DIgR2 is a member of the Ig superfamily containing ITIMs. (A) Sequences of nucleotides and deduced amino acids of DIgR2. Lines indicate signal and transmembrane sequence. The ITIM is boxed, and circled cysteines in the stalk region may allow homodimerization/heterodimerization through disulfide bridge. (B) Alignment of the amino acid sequence of DIgR2 with the most homologous human or mouse sequences. Identical amino acids are outlined in black and conservative substitutions are shaded. (C) Phylogenetic tree of the IgV of murine DIgR2 and related human and mouse sequences. (D) DIgR2 associates with SHP-1 in pervanadate-treated cells. L929 cells transiently transfected with DIgR2/Flag expression vector were pretreated with or without pervanadate (PV), then digitonin lysates of the cells were incubated with anti-Flag M2-agarose beads, and precipitates were subjected to Western blot (WB) analysis with antiphosphotyrosine (anti-pY; left) or anti-SHP-1 (right). Data represent 1 of 3 independent experiments.