Description
Enables CD4 receptor binding activity; protein phosphatase binding activity; and sialic acid binding activity. Involved in several processes, including negative regulation of calcium-mediated signaling; negative regulation of immunoglobulin production; and regulation of B cell proliferation. Located in external side of plasma membrane and neuronal cell body membrane. Is integral component of plasma membrane. Is expressed in several structures, including alimentary system; brain; hemolymphoid system gland; liver and biliary system; and reproductive system. Orthologous to human CD22 (CD22 molecule).