Discipline: Biological Sciences
Subcategory: Plant Research
Room: Exhibit Hall A
Karen Mae A. Bacalia - University of Guam
Co-Author(s): Gretchen Kroh, Colorado State University
Iron is essential for all organisms. For humans, it is an important component of hemoglobin in red blood cells, and is vital for respiration impacting both our energy levels and immunity. In plants, iron is used in photosynthesis, cellular respiration, and the formation of chlorophyll. Unfortunately, 1/3rd of the world?s population suffers from iron deficiency anemia, with majority practicing a vegetarian diet. Sadly, plants are also iron deficient, with the most notable symptom being chlorosis, or yellowing of the leaves, which also leads to decreased crop production. In previous studies, it was found that the transcripts for SufB and Ferredoxin (FD) II are down regulated early after deficiency is induced, before physiological changes. SufB is known to produce iron sulfur clusters that are used by FD II for efficient photosynthetic activity. To understand the regulation of these transcripts, promoter activity was closely studied through the addition of a reporter gene, Glucuronidase (GUS), that is not natively encoded in plants. This enzyme was chosen because it can be detected via histochemistry and qualitatively via a color change, and quantitatively via fluorescence readings. The model organism, Arabidopsis thaliana, was used for its completely sequenced genome, allowing ease in verifying molecular changes and creating transgenic lines. Through both types of GUS activity assays, it was found that transcription regulation of SufB and Ferredoxin II is possibly due to promoter activity. Future studies would include further verification if regulation takes place in the promoter and where exactly the downregulation is occurring in that region. From there, it may be possible to understand this regulation in crop plants to increase their iron content and crop yield while also helping decrease the numbers of those suffering from iron deficiency anemia.
Funder Acknowledgement(s): P. Laybourn and T. Santangelo coordinated the Colorado State University ? Biochemistry and Molecular Biosciences Summer Research program where I was able to complete this research project. Funding was provided by an NSF grant, DBI 1757514.
Faculty Advisor: Gretchen Kroh, firstname.lastname@example.org
Role: For my research project I grew the transformed plants, routinely changed the concentrations of iron through hydroponic growth, performed qualitative GUS assays, quantitative MUG assays, DNA extraction, and PCRs. I also did other tests to measure photosynthetic activity such as FMS, ICP, and Fluorocam imaging. While waiting for the plants to grow, I also made new replicates which included sterilizing seeds and making agar.