Roles of the Arabidopsis AKIP RNA-Binding-Proteins in Guard Cell Function

In plants as well as in animals, the genetic code is contained within the organism's DNA. Every cell in a multicellular organism has exactly the same DNA, and it is the regulation of which genes within that DNA are used, or 'expressed', that makes one cell different from another. This regulation occurs at many levels. DNA is transcribed (transcription) into another type of nucleic acid, RNA, which is further processed (cut, spliced, modified) before its translation into protein. Thus, regulation of gene expression can occur at the level of transcription, at the level of mRNA processing and stability, and at the level of translation. The plant hormone, abscisic acid (ABA), plays an integral role in the ability of plants to acclimate to environmental stresses such as drought, cold, and salinity, which seriously compromise crop productivity both in the U.S. and world-wide. It has been known for some time that ABA plays an important role in the regulation of gene transcription. Results from a few laboratories are now beginning to show that ABA also plays an important role in RNA metabolism. In the present research, the roles of 3 RNA binding proteins, 'AtAKIPs' in the regulation of ABA sensitivity, RNA metabolism, and drought tolerance will be investigated. Experiments will be conducted in the model organism, Arabidopsis thaliana. ABA sensitivity, drought tolerance, and RNA stability will be assessed in Arabidopsis transgenic plants that have altered amounts of each of these 3 proteins. AtAKIP RNA targets also will be identified, and computational and experimental approaches will be applied to identify consensus motifs within these RNAs that are necessary and sufficient for the RNA to bind to the AtAKIP. Once such motifs are identified, their presence will be assessed on a genome-wide basis both in Arabidopsis and in other organisms, to further scientific insight into the mechanisms of hormonally-mediated effects on RNA metabolism. The investigators are actively involved in outreach education to elementary schools. Dr. Assmann has developed teaching modules to introduce plant biology to kindergartners and has developed a video about plant gravity sensing. Dr. Bevilacqua is involved in career-site activities for 'take your child to work' day and has created chemistry demonstrations for local elementary schools. The investigators will use information obtained from the present research in the development of new laboratories for an honors undergraduate biology course, and to expand the biological aspects of the curriculum of a graduate Nucleic Acids physical chemistry class.