Leukocyte Ig-like receptor complex (LRC) in mice and men

Here, we compare the architecture of membrane receptors with extracellular lg-like domains located within the leukocyte lg-like receptor complex (LRC) of humans and mice. The receptors can be classified broadly into four groups, based on the homology of their lg-like domains and gene architecture. Receptors in the first group are characterized by the presence of the lg constant type 2-1 (lgC2-1) and variant lg (vlg) domains, and include the leukocyte lg-like receptors (LlLRs) and murine paired lg-activating receptors (PlRs). The second group of receptors possess an lgC2-2 domain and comprise the killer-cell lg-like receptors (KlRs) and platelet collagen receptor glycoprotein Vl (GPVI). The third group consists of receptors with lgC2-1, and lgC2-3 or lgC2-4 domains, and includes the receptor for lgA Fc (FCAR), NKp46 and murine Ly94. The fourth group with a single extracellular lgC2-1 domain, consists of the leukocyte-associated lg-like receptors (LAlRs). The genomic organization of and evolutionary associations between these receptors and their domains are examined.