Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: 10/9/2009
Publication Date: 1/9/2010
Citation: Valdes-Lopez, O., Yang, S.H., Graham, P.H., Reyes, J.L., Vance, C.P., Hernandez, G. 2010. Identification of Nutritional Stress-Responsive miRNAs in Phaseolus vulgaris [abstract]. XVIII Plant and Animal Genome Conference Proceedings, January 9-13, 2010, San Diego, California. Abstract W367. Interpretive Summary:
Technical Abstract: MicroRNAs (miRNAs) are key regulators for Arabidopsis development and stress responses. A hybridization approach using miRNAs-macroarrays was used to identify miRNAs that respond to nutritional stress in Phaseolus vulgaris. miRNAs-macroarrays were prepared by printing nylon filters with DNA synthetic oligonucleotides (70) complementary to reported conserved and novel (soybean and P. vulgaris) miRNAs. The expression ratios of responsive microRNAs were calculated for leaves, roots, and nodules from control or nutrient-stressed (phosphorus, nitrogen, or iron deficiency; acidic pH; and manganese toxicity) P. vulgaris bean plants. From 32 different miRNAs expressed in leaves, roots, and nodules, 25 showed significant differential expression among the organs tested. Under stress conditions, 35 miRNAs were differentially expressed, 16 of these were responsive to all the stress conditions tested. Importantly, miRNA-blot expression analysis confirmed the macroarrays results. The expression of 16 selected miRNA target genes was evaluated by RT-PCR. These results indicate that miRNAs, such as miR156/miR157, miR165/miR166, and gma-miR1532, may have relevant roles in P. vulgaris root and nodule development, while some of these have only been reported for Arabidopsis leaf and flower development. MiR167 and miR170, previously known to be involved in developmental processes, may also participate in P. vulgaris nutritional stress responses.