Os05g0553400
The rice gene OsMYB55 can enhance the vegetative growth and improve grain yield of rice growth under high temperature conditions.
Contents
Annotated Information
Function
OsMYB55 is a transcription factor of R2R3-MYBs family members.OsMYB55 binds to the promoter regions of target genes and directly activates expression of some of several genes involved in amino acids metabolism including glutamine synthetase (OsGS1;2) glutamine amidotransferase(GAT1) and glutamate decarboxylase 3 (GAD3).The MYB plant transcription factor family members regulate numerous processes during the plant life cycle and are also involved in response to various environmental stresses [1].The MYB proteins are classified into three major groups based on the number of adjacent repeats in the binding domain; R1R2R3-MYB, R2R3-MYB, and R1-MYB. Most plant MYB proteins are of the R2R3 type.The R2R3-MYBs are involved in a wide range of physiological responses such as regulation of the isopropanoid and flavonoid pathways,control of the cell cycle, root growth,and various defense and stress responses [2].Molecular and biochemical analysis revealed that OsMYB55 enhances amino acid metabolic pathways crucial for normal plant growth and development under high temperature.
Subcellular localization
The subcellular localization suggests that OsMYB55 is a nuclear protein, which is expressed in nuclei.
Expression
OsMYB55 is more Specifically Expressed at the Vegetative Stage.Expression analysis of the OsMYB55 revealed that transcript levels are higher at the vegetative stages up to tillering and the inflorescence stage. The transcription was higher in the root tissues compared to the leaves at these stages. However, its lowest expression level was observed in all seed development stages and at seed maturation.Expression analysis of the transgenic plants showed that OsMYB55 transcript levels were between fifty and ninety times higher in the transgenic lines than in the wild type plants.OsMYB55 overexpression leads to improved heat tolerance and enhances the level of total amino acids and glutamine acid, proline, arginine, and GABA in particular. It has been reported that the enhancement of amino acid biosynthesis, especially of proline, GABA and arginine has a significant impact in improving plant tolerance to different stress conditions[3].
Evolution
The 867 bp full length cDNA sequence of OsMYB55(Os05g0553400) encodes a R2R3-MYB transcription factor predicted to be 289 amino acids long. This gene was identified for nitrogen regulated genes. The BLAST search program for identifying homologs of OsMYB55 shows Oryza Sativa (Os05g0553400), Sorghum bicolor (242088749), Zea mays (226509454), Vitis vinifera (296081600), Populus trichocarpa (224092242), Malus x domestica (71041104), Dacus carota (134026414), Glycine max (255642827) and Arabidopsis thaliana (15242793).
Knowledge Extension
Overexpression of OsMYB55 leads to increased heat tolerance of rice plants during the vegetative stage. This leads to increased biomass and if the plants are subsequently grown under moderate conditions leads to increased seed yield[4]. One explanation for this is that increasing the amino acid content at the vegetative stage through the action of OsMYB55 could help the plant in the flower initiation process which occurs at this stage thus resulting in a higher yield when compared to the wild type plants. This trait will become of increasing importance as crop yields in many important rice growing regions are decreased due to higher temperatures given global warming. Therefore, it is of great importance to explore different crop genetic solutions to ameliorate.These amino acids have multifunctional roles in plants that help plant tissues resist and recover from stress [5]. Additionally, arginine has been reported to have a major role in improving wheat yield under high temperature conditions [6].
Labs working on this gene
Please input related labs here.
* Department of Biochemistry and Molecular Biology, Mississippi State University, MS 39762, USA; * Institute of Biotechnology, Viikinkaari 1, FI-00790, University of Helsinki, Finland * Science Complex, University of Guelph, Guelph, Ontario, Canada * Gustavo Bonaventure, Max Planck Institute for Chemical Ecology, Germany
References
- ↑ Smolen GA, Pawlowski L, Wilensky SE, Bender J (2002) Dominant alleles of the basic helix-loop-helix transcription factor ATR2 activate stress-responsive genes in Arabidopsis. Genetics 161: 1235–1246.
- ↑ Raffaele S, Vailleau F, Leger A, Joubes J, Miersch O, et al. (2008) A MYB transcription factor regulates very-long-chain fatty acid biosynthesis for activation of the hypersensitive cell death response in Arabidopsis. Plant Cell 20: 752–767.
- ↑ Kinnersley AM, Turano FJ (2000) Gamma Aminobutyric Acid (GABA) and Plant Responses to Stress. Crit Rev Plant Sci 19: 479–509.
- ↑ Ashraf El-kereamy;Yong-Mei Bi;Kosala Ranathunge;Perrin H. Beatty;Allen G. Good;Steven J. Rothstein The Rice R2R3-MYB Transcription Factor OsMYB55 Is Involved in the Tolerance to High Temperature and Modulates Amino Acid Metabolism PLoS ONE, 2012, 7(12): e52030
- ↑ Szabados L, Savoure´ A (2010) Proline: a multifunctional amino acid. Trends in Plant Science 15: 89–97.
- ↑ Hozayn M, Abd El-Monem AA (2010) Alleviation of the potential impact of climate change on wheat productivity using arginine under irrigated Egyptian agriculture. Opions Me´diterrane´ennes. 95: 95–100.
