ACCELERATION OF PUBERTY ONSET IN FEMALE MICE BY MALE URINARY PROTEINS

1. Puberty onset in female mice is accelerated by exposure to conspeci fic adult male urine, which acts through the vomeronasal organ and the accessory olfactory system. A distinctive component of adult male mou se urine is the major urinary protein complex (MUP), which is a lipoca lin; it has a hydrophobic pocket that binds small endogenous volatile molecules. The MUP gene family also codes for a hexapeptide, which has four residues in common with the N-terminal region of MUP. 2. MUP, th e volatiles bound to MUP and the MUP-related hexapeptide have been tes ted for the induction of puberty acceleration by measuring the increas e in uterus weight related to the first pro-oestrus phase. MUP, togeth er with its bound volatiles, induces puberty acceleration. Its activit y is retained even when the volatiles have been removed either by orga nic extraction or competition displacement with a high-affinity ligand . 3. MUP-related hexapeptide also induces puberty acceleration in fema le mice. In contrast, the odorants bound to MUP do not exert this effe ct. 4. It is proposed that the vomeronasal organ contains receptors th at recognize the short N-terminal consensus sequence, N-Glu-Glu-Ala-X- Ser (where X is a polar residue), common to both MUP and the hexapepti de.