Enables receptor ligand activity; substance K receptor binding activity; and substance P receptor binding activity. Involved in positive regulation of cytosolic calcium ion concentration. Acts upstream of or within positive regulation of saliva secretion and tachykinin receptor signaling pathway. Predicted to be located in extracellular region. Predicted to be active in extracellular space. Is expressed in brain; mammary gland; skin; spleen; and stomach. Orthologous to human TAC4 (tachykinin precursor 4). [provided by Alliance of Genome Resources, Apr 2022]