A novel CRISPR/Cas9 transgenic mouse model for in vivo studies on EPPIN, a sperm-based male contraceptive drug target.

• Grant number: 23/03529-4
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: May 01, 2023
• End date: April 30, 2025
• Field of knowledge: Biological Sciences - Pharmacology - Biochemical and Molecular Pharmacology
• Principal Investigator: Erick José Ramo da Silva
• Grantee: Célio Junior da Costa Fernandes
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Associated research grant: 21/06718-7 - Translational studies on the sperm-binding protein EPPIN as a male contraceptive drug target, AP.JP2

Abstract

Novel male contraceptive strategies will foster the participation of men in family planning and sharing the contraceptive burden with women. The sperm protein EPPIN (epididymal protease inhibitor) is a target for non-hormonal, on-demand male contraceptive drug development. The physiological relevance of EPPIN is driven by its role as a sperm-surface binding site for seminal plasma proteins such as human SEMG1 and its mouse ortholog SVS2, leading to transient inhibition of sperm fertilizing ability. Although single-nucleotide polymorphisms in the human EPPIN gene have been associated with idiopathic male infertility due to sperm motility aberrations, little is known about its requirement for mammalian reproduction in vivo. Given the functional conservation between mouse and human EPPIN orthologs, the generation of a transgenic mouse model will provide important insights into its roles on male fertility while bearing the potential to clinical research on male contraception. We hypothesize that targeted Eppin deletion in mice will cause infertility or subfertility phenotype due to sperm aberrations caused by the absence of EPPIN-mediated protein-protein interactions. This project aims to develop an Eppin-deficient (Eppin KO) mouse model using CRISPR/Cas9 technology and determine its reproductive phenotype, including breeding performance, sex hormone levels, sperm quantitative and functional parameters, and testicular and epididymal histology. This knowledge will expand the current understanding of EPPIN requirement for protein-protein interactions that dictate sperm function in vivo, contributing to the mechanistic understanding of sperm physiology and as tools for investigations of male contraceptive drug targets.