Predicted to enable several functions, including interleukin-16 binding activity; interleukin-16 receptor activity; and protein homodimerization activity. Involved in helper T cell enhancement of adaptive immune response. Acts upstream of or within several processes, including defense response to Gram-negative bacterium; positive regulation of calcium-mediated signaling; and positive regulation of peptidyl-tyrosine phosphorylation. Located in endoplasmic reticulum; external side of plasma membrane; and membrane raft. Is expressed in several structures, including alimentary system; brain; genitourinary system; hemolymphoid system; and liver and biliary system. Used to study type 1 diabetes mellitus. Human ortholog(s) of this gene implicated in immunodeficiency 79. Orthologous to human CD4 (CD4 molecule).
