| Title: | Tobacco drought stress responses reveal new targets for Solanaceae crop improvement |
| Author(s): | Rabara RC; Tripathi P; Reese RN; Rushton DL; Alexander D; Timko MP; Shen QJ; Rushton PJ; |
| Address: | "Texas A&M AgriLife Research and Extension Center, Dallas, Texas, 75252, USA. roel.rabara@tamu.edu. Molecular and Computational Biology Section, Dana & David Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, CA, USA. tprateek@dornsife.usc.edu. Department of Biology and Microbiology, South Dakota State University, Brookings, SD, 57007, USA. Neil.Reese@sdstate.edu. Department of Biological Sciences, University of North Texas, Denton, TX, 76203, USA. dlrushton82@gmail.com. Metabolon, Inc., 617 Davis Drive, Durham, NC, 277133, USA. DAlexander@metabolon.com. Department of Biology, University of Virginia, Charlottesville, Virginia, 22904, USA. mpt9g@virginia.edu. School of Life Sciences, University of Nevada, Las Vegas, 89154, USA. jeffery.shen@unlv.edu. Texas A&M AgriLife Research and Extension Center, Dallas, Texas, 75252, USA. paul.rushton@tamu.edu" |
| DOI: | 10.1186/s12864-015-1575-4 |
| ISSN/ISBN: | 1471-2164 (Electronic) 1471-2164 (Linking) |
| Abstract: | "BACKGROUND: The Solanaceae are an economically important family of plants that include tobacco (Nicotiana tabacum L.), tomato, and potato. Drought is a major cause of crop losses. RESULTS: We have identified major changes in physiology, metabolites, mRNA levels, and promoter activities during the tobacco response to drought. We have classified these as potential components of core responses that may be common to many plant species or responses that may be family/species-specific features of the drought stress response in tobacco or the Solanaceae. In tobacco the largest increase in any metabolite was a striking 70-fold increase in 4-hydroxy-2-oxoglutaric acid (KHG) in roots that appears to be tobacco/Solanaceae specific. KHG is poorly characterized in plants but is broken down to pyruvate and glyoxylate after the E. coli SOS response to facilitate the resumption of respiration. A similar process in tobacco would represent a mechanism to restart respiration upon water availability after drought. At the mRNA level, transcription factor gene induction by drought also showed both core and species/family specific responses. Many Group IX Subgroup 3 AP2/ERF transcription factors in tobacco appear to play roles in nicotine biosynthesis as a response to herbivory, whereas their counterparts in legume species appear to play roles in drought responses. We observed apparent Solanaceae-specific drought induction of several Group IId WRKY genes. One of these, NtWRKY69, showed ABA-independent drought stress-inducible promoter activity that moved into the leaf through the vascular tissue and then eventually into the surrounding leaf cells. CONCLUSIONS: We propose components of a core metabolic response to drought stress in plants and also show that some major responses to drought stress at the metabolome and transcriptome levels are family specific. We therefore propose that the observed family-specific changes in metabolism are regulated, at least in part, by family-specific changes in transcription factor activity. We also present a list of potential targets for the improvement of Solanaceae drought responses" |
| Keywords: | "Droughts Ketoglutaric Acids/metabolism Metabolome Phylogeny Plant Growth Regulators/metabolism Plant Leaves/genetics/metabolism Plant Proteins/classification/genetics/metabolism Plant Roots/genetics/metabolism Plants, Genetically Modified/growth & develop;" |
| Notes: | "MedlineRabara, Roel C Tripathi, Prateek Reese, R Neil Rushton, Deena L Alexander, Danny Timko, Michael P Shen, Qingxi J Rushton, Paul J eng Research Support, Non-U.S. Gov't England 2015/07/01 BMC Genomics. 2015 Jun 30; 16(1):484. doi: 10.1186/s12864-015-1575-4" |
