Extraction, characterization, and binding analysis of two pheromonally active ligands associated with major urinary protein of house mouse (Mus musculus).

Mouse urine contains substantial quantities of a family of proteins (MUPs) that are members of the lipocalycin family of proteins and that are potentially capable of binding hydrophobic molecules. We have used gas chromatography-mass spectrometry (GC-MS) to characterize two ligands associated with the MUPs, a thiazole and a brevicomin derivative. Previous work has suggested a role for these two ligands as androgen-dependent pheromones. In urine, nearly all of these ligands are protein bound and fractionation of MUPs on Mono-Q anion exchange chromatography indicated some specificity of ligand binding by the MUP subclasses.