| Primary Identifier | IPR002971 | Type | Family |
| Short Name | Maj_urinary |
| description | Rodent urinary proteins (mouse major urinary proteins or MUPs and rat alpha-2u globulins) are the major protein components of rodent urine and transport pheromones [].Rodent urine contains an unusually large amount of protein. The major site of MUP synthesis is the liver; the protein is secreted by the liver into serum, where it circulates at relatively low levels before being rapidly filteredby the kidney and excreted.The sex-dependent expression of MUP (adult male mice secrete 5-20 times as much MUP as do females) and its ability to bind a number of odorant molecules is consistent with the suggestion that MUP acts as a pheromonetransporter; the protein may be excreted into the urine carrying a boundpheromone, which is released as the urine dries and the protein denatures.The crystal structure of MUP has been solved []and is known to be a member of the lipocalin family. Alpha-2u-globulin, a close homologue of MUP, accounts for 30-50% of totalexcreted protein in adult male rat urine. As its electrophoretic mobilityis similar to that of serum a2 globulin, it was named 'alpha-2u-globulin',the subscript 'u' denoting its origin in urine. Alpha-2u-globulin is secreted into the plasma by a number of tissues, where it circulates beforefiltration through the kidney; between 20 and 50% is reabsorbed by theproximal tubule of the nephron, the rest being excreted. Although the exactphysiological role of alpha-2u-globulin is unclear, there is circumstantialevidence that it functions in pheromone transport. This is consistent withits observed binding properties, its close similarity with MUP and the knownproperties of male rat urine.Some of the proteins in this family are allergens. Allergies are hypersensitivity reactions of the immune system to specific substances called allergens (such as pollen, stings, drugs, or food) that, in most people, result in no symptoms. A nomenclature system has been established for antigens (allergens) that cause IgE-mediated atopic allergies in humans [WHO/IUIS Allergen Nomenclature SubcommitteeKing T.P., Hoffmann D., Loewenstein H., Marsh D.G., Platts-Mills T.A.E.,Thomas W. Bull. World Health Organ. 72:797-806(1994)]. This nomenclature system is defined by a designation that is composed ofthe first three letters of the genus; a space; the first letter of thespecies name; a space and an arabic number. In the event that two speciesnames have identical designations, they are discriminated from one anotherby adding one or more letters (as necessary) to each species designation.The allergens in this family include allergens with the following designations: Mus m 1 and Rat m 1. |
