Major urinary proteins
![Tertiary structure of a mouse major urinary protein. The protein has eight beta sheets (yellow) arranged in a beta barrel open at one end, with alpha helices (red) at both the amino- and carboxyl termini. The structure is resolved from Protein Data Bank entry 1i04.
Find all instances of this protein in the PDB](/Images/godic/202501/25/Mup1_PDB_1i044958.png")
![Phylogeny of Mup coding sequences in mammals.[1] The repeatability of the reconstruction was tested by bootstrapping. Interior branches with bootstrap support > 50% are shown.](/Images/godic/202501/25/Phylogenetic_tree_of_Mups4958.jpg")
![A dot plot showing self-similarity within the mouse Mup cluster.[20] The main diagonal represents the sequence's alignment with itself; lines off the main diagonal represent similar or repetitive patterns within the cluster. The pattern differs between the older, peripheral Class A and the newer, central Class B Mups.](/Images/godic/202501/25/Mup_locus_showing_DNA_repeats4958.jpg")
![Mouse major urinary proteins bind 2-sec-butyl-4,5-dihydrothiazole (SBT), a mouse pheromone.[24] The beta barrel forms a pocket, in which the SBT molecule is tightly bound. The structure is resolved from 1MUP.](/Images/godic/202501/25/MupwithSBT4958.jpg")
Major urinary proteins (Mups), also known as α2u-globulins, are a subfamily of proteins found in abundance in the urine and other secretions of many animals. Mups provide a small range of identifying information about the donor animal, when detected by the vomeronasal organ of the receiving animal. They belong to a larger family of proteins known as lipocalins. Mups are encoded by a cluster of genes, located adjacent to each other on a single stretch of DNA, that varies greatly in number between species: from at least 21 functional genes in mice to none in humans. Mup proteins form a characteristic glove shape, encompassing a ligand-binding pocket that accommodates specific small, organic chemicals.