Grant: $988,389 - National Science Foundation - Jul. 1, 2009
25% voted satisfied - 75% voted not satisfied - 4 vote(s) cast
Award Description: Crassulacean acid metabolism (CAM), a photosynthetic pathway found in approximately 7% of all vascular plant species that improves water use efficiency up to 10-fold relative to C3 species, provides an exquisite example of circadian and environmentally regulated photosynthetic adaptation. CAM plants display distinctive circadian clock outputs and inverse stomatal rhythms, which are not found in C3 or C4 plants. The long-term goals of the proposed research are to identify the regulatory and signaling pathways essential for the circadian control of CAM and inverse stomatal behavior, respectively. The common or crystalline ice plant will be used as a model to determine the environmentally induced, circadian controlled changes in mRNA and protein abundance, and reversible protein phosphorylation events during the transition from C3 photosynthesis to CAM by conducting mRNA expression profiling. Metabolite changes will also be monitored to determine if they participate in possible feedback control circuits of upstream circadian clock gene expression outputs. Key regulatory and signaling factors that function in the CAM circadian clock will also be analyzed. Increased understanding of the molecular mechanisms responsible for controlling the expression and regulation of CAM will provide new knowledge about the molecular basis of this important water-saving photosynthetic adaptation that will provide novel strategies for improving crop productivity in the context of global climate change. This project will provide unique 'hands-on training opportunities in plant research for undergraduate, graduate and post-doctoral students. Undergraduate students will be selected from established outreach programs at the University of Nevada (UNR) that target students from disadvantaged backgrounds to participate in developing a 'Plants Have Rhythm educational display and K-12 teaching module to inform and excite high school, college students, and the general public about CAM and the existence of circadian rhythms in plants and their adaptive significance. 2
Project Description: Research Aim 1. To determine the environmentally induced, circadian controlled changes in mRNA abundance during the transition from C3 photosynthesis to CAM by conducting mRNA expression profiling using cDNA sequence data sets derived from massively parallel DNA sequencing. The 454 transcriptome pyrosequencing has been completed. Results from GS-FLX TITANIUM sequencing from a normalized cDNA library from C3 and CAM performing leaves, roots, and flowers generated 2,380,901 reads resulting is 765 MB of sequence. These data, along with included 27,347 ESTs derived from Sanger sequencing, were combined to create 41,374 contigs and 96,490 singletons. The contigs were then used to design a custom, probe optimized, NimbleGen oligonucleotide microarray containing 133,848 probes (4 per gene). The custom array was then hybridized with cDNA from leaves sampled every 4 h over the course of a 48 h time course. Data analysis will commence once the results are obtained.
Jobs Summary: Graduate student The graduate student will receive training in molecular cloning, DNA sequencing, RNA isolation, (real time) RT-PCR, 454 Sequencing™ and microarray data analysis and the functional testing of phototropin genes using transient and stable transformation assays under the direction of the PI and Co-PIs. The technician and graduate student will also mentor undergraduate and high school students in the training and outreach programs. Undergraduate student The undergraduate student will participate in year round (summer full-time and semester part time) research activities and support, and assist with outreach activities, and will help mentor Upward Bound high school students during the summer months. (Total jobs reported: 2)
Project Status: Less Than 50% Completed
This award's data was last updated on Jul. 1, 2009. Help expand these official descriptions using the wiki below.