Project 443177

One potent mechanism of gene regulation is mediated through small RNA pathways. Small RNA pathways are found across all three kingdoms of life, and at the core of these pathways are the conserved family of Argonaute effectors. Argonaute proteins are guided via the sequence specificity of small RNA effector molecules (think of these as postal codes) to identify target transcripts for gene regulation. Although initially characterized as posttranscriptional modulators of gene expression, studies of Argonautes in various species have revealed novel functions. The model nematode C. elegans has contributed an abundance of knowledge to our understanding of small RNA pathways. C. elegans possesses 19 Argonaute genes, more than in humans (which have 8). Most Argonautes that have been studied in C. elegans thus far have been examined for their roles in somatic tissues or in oogenesis. In contrast, the roles of small RNA pathways in regulating gene expression during spermatogenesis remain relatively enigmatic, yet sperm contribute half of the genome and other epigenetic components to progeny. Our team has identified a set of 12 Argonautes that are expressed during spermatogenesis, pointing to important roles for these pathways in sperm production and fertility. We will utilize a powerful constellation of cutting edge genetic, genomic, proteomic, molecular biology and biochemistry approaches to determine the molecular mechanisms by which these small RNA pathways impact sperm development and fertility. Because of their central role in gene regulation and their profound impact on the development and differentiation of many organisms, uncovering novel and conserved molecular mechanisms of Argonaute/small RNA pathways is key to advancing our fundamental knowledge of normal cellular functions, and has the potential to enable more precise means of manipulating gene expression--both of which are important for biotechnology applications and therapeutics, including fertility treatment.