Our laboratory studies the basic biology of spermatogonial stem cells (SSCs), which are adult-tissue stem cells responsible for sperm production in the mammalian testis and which are essential for male fertility. Ongoing studies in the lab are focused on 1) determining how these cells are regulated and behave like stem cells, 2) how we can prevent SSC loss due to sterilizing treatments, 3) how SSCs participate in the etiology of male infertility, and 4) how the male germline ages. Our work has potential implications for basic stem cell biology, reproduction, as well as translational significance for treatment and prevention of male infertility. The approaches we use in the lab are multidisciplinary, including animal models (rodents, primates), human tissues, an in vitro SSC culture system, an in vivo transplantation assay for stem cells, various wide-field microscopy techniques, as well as conventional and high-throughput molecular biology and genomic approaches.