Secretoglobin, family 1A, member 1 (uteroglobin)

The founding member of the secretoglobin family of small, secreted, disulphide-bridged dimeric proteins found only in mammals. This antiparallel disulfide linked homodimeric protein is multifunctional and found in various tissues in various names such as: Uteroglobin (UG, UGB), Uteroglobin-like Antigen (UGL), Blastokinin, Clara cell secretory protein (CCSP), Clara cell 16 kD protein (17 in rat/mice), Clara Cell-Specific 10 kD Protein (CC10), human protein 1, urine protein 1 (UP-1), polychlorinated biphenyl-binding protein (PCB-BP), human Clara Cell Phospholipid-Binding Protein (hCCPBP), Secretoglobin 1A member 1 (SCGB1A1).

Function
Real physiological role is not known. Putative functions are:
 * 1) Immunomodulation:
 * 2) Progesterone binding: weak in some animals, especially weak in humans. (Note: UGB is itself progesterone induced gene in the endometrium.)
 * 3) Inhibits phospholipase A2
 * 4) binds phosphatidylcholine, phosphatidylinositol,
 * 5) Binds to fibronectin: The uteroglobulin knockout mice develop Goodpasteur like glomerulopathy due to fibronectin binding of IgA which might potentially be prevented by uteroglobin replacement. However contrary to the animal model claims, human genetic data might suggest that the effect may be indirect
 * 6) Target of Polychlorinated biphenyl (pcb) binding