Predicted to enable signaling receptor activity. Predicted to be involved in immune response-regulating cell surface receptor signaling pathway. Predicted to act upstream of or within cell surface receptor signaling pathway; negative regulation of B cell proliferation; and negative regulation of alpha-beta T cell proliferation. Predicted to be located in external side of plasma membrane. Predicted to be integral component of plasma membrane. Orthologous to human BTLA (B and T lymphocyte associated). [provided by Alliance of Genome Resources, Apr 2022]