Negative regulation of cadmium tolerance in Arabidopsis by MMDH2
Autor: | Xi Wu, Sheng Yibao, Tingting Fan, Wei Wang, Xiangyu Zhu, Alia Shah, Yangyang Han, Shuqing Cao |
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Rok vydání: | 2019 |
Předmět: |
0106 biological sciences
0301 basic medicine Mutant Arabidopsis Plant Science Biology Models Biological 01 natural sciences Malate dehydrogenase 03 medical and health sciences chemistry.chemical_compound Gene Expression Regulation Plant Malate Dehydrogenase Stress Physiological Genetics Amino Acid Sequence Gene chemistry.chemical_classification Reactive oxygen species Gene knockdown Arabidopsis Proteins Hydrogen Peroxide General Medicine Malondialdehyde biology.organism_classification Cell biology 030104 developmental biology chemistry Gene Knockdown Techniques ATP-Binding Cassette Transporters Efflux Reactive Oxygen Species Sequence Alignment Agronomy and Crop Science Cadmium Signal Transduction 010606 plant biology & botany |
Zdroj: | Plant Molecular Biology. 101:507-516 |
ISSN: | 1573-5028 0167-4412 |
Popis: | MMDH2 gene negatively regulates Cd tolerance by modulating reactive oxygen species (ROS) levels and the ROS-mediated signaling, thus, affecting the expression of PDR8. The molecular mechanism by which plants respond to stress caused by cadmium (Cd), one of the most toxic heavy metals to plants, is not well understood. Here, we show that MMDH2, a gene encoding mitochondrial malate dehydrogenase, is involved in Cd stress tolerance in Arabidopsis. The expression of MMDH2 was repressed by Cd stress. The mmdh2 knockdown mutants showed enhanced Cd tolerance, while the MMDH2-overexpressing lines were sensitive to Cd. Under normal and Cd stress conditions, lower H2O2 levels were detected in mmdh2 mutant plants than in wild-type plants. In contrast, higher H2O2 levels were found in MMDH2-overexpressing lines, and they were negatively correlated with malondialdehyde levels. In addition, the expression of the PDR8, a gene encoding a Cd efflux pump, increased and decreased in the mmdh2 mutant and MMDH2-overexpressing lines, in association with lower and higher Cd concentrations, respectively. These results suggest that the MMDH2 gene negatively regulates Cd tolerance by modulating reactive oxygen species (ROS) levels and the ROS-mediated signaling, thus, affecting the expression of PDR8. |
Databáze: | OpenAIRE |
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