Intellectual merit: Eukaryotes use a wide range of mechanisms to regulate gene expression. Of particular significance is the transport of messenger RNAs (mRNAs) to particular locations within cells where they are translated in a spatially controlled manner. Processes that depend on the correct spatial and temporal localization of different mRNA transcripts include asymmetric cell division and the establishment of body axes during early development. Many different factors (proteins or other RNAs) can associate with each transcript to ensure its export from the nucleus and its transport to the correct location in the cell. These dynamic interactions between mRNAs and proteins are best studied by visualization of individual mRNA:protein (mRNP) complexes in living cells. Using Drosophila melanogaster as the model developmental system, this project aims to decipher the dynamic composition of a key mRNA transcript that governs axial body patterning during oogenesis. The specific objectives include:
1) To co-visualize specific mRNA transcripts and the protein factors that bind to them to inhibit their translation into proteins while they are being transported to their target sites in living egg chambers. 2) To determine whether small regulatory RNAs (microRNAs) that are predicted to bind to this transcript repress its translation to make protein during its transport in oogenesis. 3) To establish which components of the RNA interference (RNAi) pathway target the mRNPs to specialized cytoplasmic regions for storage or decay. An integrated suite of molecular, genetic, biochemical, biophysical and advanced imaging approaches will be applied to complete these objectives.
Completion of this project will increase our understanding of the mechanisms by which spatio-temporal gene expression is achieved, especially the interactions of RNA-transport machinery with cellular components responsible for RNAi, RNA storage and RNA turnover in living cells.
Broader Impact: This project will provide undergraduate and graduate students the opportunity to apply innovative fluorescence imaging techniques to address important biological questions using a powerful genetic model system. The PI will actively recruit, mentor and encourage students from groups underrepresented in the sciences to work on the project, and serve as a role model for young female scientists. The PI will continue to improve and expand an existing course in advanced fluorescence microscopy that she has developed at Hunter College. Her hands-on approach to teaching life sciences and her use of visualization tools to reveal the intricacies of biological pathways, enable students to understand and connect with science beyond textbooks. The educational framework of this project is designed so that all students, regardless of cultural background, will gain valuable experience that will prepare them for demanding graduate programs, post-doctoral positions and the large number of jobs that require experience in biotechnology and handling of model organisms. Moreover, this project will raise the scientific literacy of the public via presentations by the PI and her students of research results at local forums such at New York Academy of Sciences and CUNY Science Café.
