Regulation of nitrogen assimilation in marine diatoms: Investigation of the importance of post-transcriptional processes

Clark University, Worcester MA

Investigators

Abstract

Diatoms are unicellular photosynthetic plankton that contribute significantly to global carbon, nitrogen, and silicate biogeochemical cycles. Diatoms are estimated to account for 40% of the carbon fixed in marine ecosystems and 20% of the primary productivity on Earth. They exhibit rapid growth in response to increases in nitrogen availability, which in marine ecosystems, varies over several spatial (meters to kms) and temporal (hours to months) scales. Thus, the productivity and ecological success of diatoms can, in part, be attributed to their ability to rapidly sense and respond to fluctuations in nitrogen source and supply. In all living cells, the regulation of gene expression is a multifaceted and dynamic process. Cells integrate intrinsic and environmental signals into multiple regulatory pathways allowing for coordinated gene expression and cellular function. This project uses molecular approaches to explore the hypothesis that in marine diatoms, post-transcriptional regulation of genes involved in nitrogen transport and assimilation is mediated by changes in messenger RNA stability and allows for rapid metabolic response to changes in nutrient source or supply. The increased availability of diatom genome sequences and advances in DNA transformation capabilities have stimulated biotechnological explorations using diatoms, including both nutritional and industrial applications. The ability to engineer and regulate gene expression post-transcriptionally will aid in the development of new biotechnological tools needed to study and regulate gene expression in diatoms. The research program provides training opportunities for undergraduate and graduate students and a post-doctoral scholar. The project will contribute to teacher training, and thus science education throughout the Worcester community, by working collaboratively with faculty in the Jacob Hiatt Center for Urban Education at Clark University to develop a K-16 "learning progression" exploring climate change while providing enhanced science training to pre- and in-service public school teachers.