NCBI Summary:
The protein encoded by this gene is a plasma glycoprotein of unknown function. The protein shows sequence similarity to the variable regions of some immunoglobulin supergene family member proteins. [provided by RefSeq, Jul 2008]
General function
Extracellular binding protein
Comment
Cellular localization
Secreted
Comment
Ovarian function
Comment
Expression regulated by
Comment
Ovarian localization
, Follicular Fluid
Comment
Apolipoprotein A-IV as a novel gene associated with polycystic ovary syndrome. Kim YS et al. Polycystic ovary syndrome (PCOS) is a common endocrine-metabolic disorder, affecting 6-10% of women of reproductive age. The etiology remains poorly understood. To investigate the differentially expressed proteins from PCOS patients versus healthy women, the protein expression in follicular fluid was analyzed using two-dimensional electrophoresis (2-DE). Since follicular fluid contains a number of secretory proteins required for oocyte fertilization and follicle maturation, it is possible that follicular fluid can be used as a provisional source for identifying pivotal proteins associated with PCOS. In this study, six overexpressed proteins [kininogen1, cytokeratin9, antithrombin, fibrinogen ?-chain, apolipoproteinA-IV (apoA-IV) precursor and a-1-B-glycoprotein (A1BG)] in follicular fluids from PCOS patients were identified with matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF-MS) and nano LC-MS/MS. Western blot analysis confirmed that the protein expression levels of apoA-IV precursor and A1BG were increased in follicular fluid from PCOS patients compared with those from normal controls. The analysis of protein expression for other proteins revealed individual variation. These results facilitate the understanding of the molecular mechanisms of PCOS and provide candidate biomarkers for the development of diagnostic and therapeutic tools.