Research Projects

Female infertility can be caused by physiological abnormalities, endocrine system imbalances, or genetic factors. About 10-20% of infertility in females is idiopathic, with the causative factor unknown. In mammals, successful fertilization occurs when a capacitated sperm crosses the cumulus layer of cells surrounding the oocyte before interacting with its outermost glycoproteinaceous matrix (Zona Pellucida; ZP). Defects in the interaction between the sperm and oocyte at the ZP or plasma membrane can also cause infertility. ZP2 is crucial for fertilization, as Zp3-/- and Zp2-/- female mice are infertile, while Zp1-/- female mice have reduced fertility. Post-fertilization, Ovastacin cleaves ZP2 into two polypeptides, which prevent multiple sperm from binding and fuseing with a fertilized egg. This block is essential in mammals as polyspermy-formed embryos are not genetically viable and die within days. Single nucleotide polymorphisms (SNPs) are the most common type of genetic variations associated with various diseases, including polycystic ovarian disease and possibly contributing to idiopathic female infertility. Mutations in the sperm binding region or Ovastacin cleavage site of hZp2 may cause structural/functional changes that influence sperm-oocyte interaction and ultimately lead to female infertility, especially in females with normal pathophysiology. It is imperative to investigate the correlation between SNPs in these regions of the hZp2 gene and idiopathic female infertility. This can be done by identifying these SNPs using bioinformatics and genomic analysis, followed by characterizing their functional effects on sperm binding, protein secretion, and interaction with other zona proteins through in vitro assays.