Is predicted to encode a protein with the following domains: Immunoglobulin domain; Immunoglobulin I-set; Immunoglobulin subtype 2; Immunoglobulin subtype; Immunoglobulin-like fold; Immunoglobulin-like domain superfamily; Immunoglobulin I-set domain; Immunoglobulin V-set domain; CD80-like C2-set immunoglobulin domain; Immunoglobulin-like domain; and CD80-like, immunoglobulin C2-set. Is an ortholog of C. elegans syg-1 and zig-1.