Pheromone produced by juveniles which activates a small number of vomeronasal organ sensory neurons and exhibits a powerful inhibitory effect on adult male mating behavior. Secreted from the lacrimal gland into tears. Expressed in acinar cells of the lacrimal gland from where it is secreted into tears. Not detected in a range of other tissues tested including other exocrine glands, internal organs and sensory epithelia. Expressed maximally between 2 and 3 weeks of age. Levels decrease sharply after 4 weeks around puberty. Expression is 50-fold higher in juveniles than adults with similar levels in male and female juveniles. Not expressed in castrated or ovariectomized adults. Highly expressed in juveniles of strains BALB/C and C56BL/5 but expression is not detected in juveniles of strains CBA or C3H/He. Belongs to the exocrine gland-secreted peptide family.