In the germline and early embryo, we are studying the functions of an RNA-protein complex and putative mRNA storage granules that contain the RNA binding proteins CGH-1 and CAR-1. These two proteins are conserved components of P bodies, cytoplasmic RNA-protein particles that serve as sites of decapping-dependent mRNA degradation, sequestration of translationally silenced mRNAs, and regulation by micro-RNAs. C. elegans provides a powerful system for studying P body functions and regulation in vivo. We are investigating how CGH-1/CAR-1 particles influence maternal mRNA metabolism and translational regulation during oogenesis, and in the early embryo. An interesting feature of CGH-1 and CAR-1 is that they are among a relatively small group of proteins that are required to prevent excessive levels of germ cell death by apoptosis. A conserved but little understood feature of germ cell development is that around the late pachytene stage of meiosis, a high proportion of developing oocytes undergo apoptosis. We believe that by investigating how this cell death is regulated, and is influenced by CGH-1 and CAR-1, we will elucidate aspects of germ cell development that are both important and conserved.

In the early C. elegans embryo, we have studied mechanisms that silence transcription globally in the germline precursor lineage, and have investigated how particular transcription regulators contribute to the unfolding of the new transcription repertoire. We are currently studying gene regulation events associated with oocyte maturation, a conserved process through which oocytes are stimulated to progress through the meiotic cell cycle, and are prepared for fertilization and the early stages of embryogenesis.