Steroid hormones control fundamental physiological functions via both genomic and non-genomic pathways. Canonical steroid hormone signaling requires that a hormone must pass through the plasma membrane, bind to its genomic receptor, and together they migrate into the nucleus and modulate gene expression. However, steroid hormmones can also signal via a non-canonical, non-genomic steroid signaling pathway. Previous research has established that non-genomic signaling plays a vital role in human sperm cell activation and modulation of pain perception by dorsal root ganglion neurons (DRG). However, the molecular determinants of this pathway are poorly understood. In this project, we aim to reveal the precise molecular signaling cascade that takes place in sperm cells and DRG neurons upon progesterone treatment. The knowledge obtained from these studies will be crucial for the development of new pain management therapies; it will also stimulate development of diagnostic tests and treatments for male infertility.