Geneticists measure time in generations and celebrate immortality with reproductive success. My lab is driven by a passion to understand the cell biological basis of gamete (sperm and egg) development. We study how germline stem cells balance self-renewal with differentiation. Stem cell self-renewal at the expense of differentiation can cause germ cell tumors while differentiation at the expense of self-renewal can cause sterility. Our long-term goal is to understand the mechanisms that regulate germline stem cell fate. Other research interests include understanding the molecular function of the hormone testosterone in spermatogenesis. Our work has revealed that specialized tight junctions between Sertoli cells, which are integral to the blood/testis barrier, are regulated by testosterone. We are studying how germ cells pass through these tight junctions without compromising barrier function. We are also investigating molecular mechanisms of translational regulation—a major form of gene regulation in both male and female germ cells—during spermatogenesis. We use both forward and reverse genetics to identify the genes involved. Phenotypic analysis includes microscopy, biochemistry and cell physiology.
