During the development of multicellular organisms, proper cell fates can be specified by asymmetric cell divisions, where key molecules are distributed unequally between two sister cells. Despite the importance of this mechanism for normal development, it remains poorly understood. The embryo of the mollusc Ilyanassa has numerous asymmetric cell divisions and important practical and experimental advantages, making it a useful model for understanding this process. This group of researchers has discovered that many RNA molecules in the embryo are specifically localized and segregated during early development by a novel mechanism. This project will empirically determine the sequences that control localization and asymmetric segregation of these RNAs, allowing comparison of the RNA structures that mediate similar and different patterns of localization. The identification of these RNA sequences will then allow these researchers to test hypotheses about how the specificity of localization is achieved. These experiments will also test whether the localization of one of these RNAs is important for cell fate specification by using functional gene-knockdown approaches. These experiments should significantly expand understanding of how RNAs are sorted during cell division, and how this impacts early embryogenesis. The work will also train young scientists at the graduate and undergraduate levels for future careers as independent researchers and scholars in this underexplored area of cell differentiation.
