This study demonstrates changes in the methylation status of the pyruvate dehydrogenase (PDH) gene promoter in corn leaves under acute salt stress. Using bisulfite sequencing, we assessed changes in cytosine methylation at CG sites, which may regulate the transcriptional activity of the gene under study. To assess the methylation status, a fragment of the PDH-E1 gene promoter was amplified and sequenced after preliminary bisulfite conversion of DNA. The methylation level of CpG sites in the studied fragment was shown to increase significantly from 66.7 % in the control to 77.8 % after 6 hours and 88.9 % after 12 and 24 hours of stress. Real-time PCR analysis of the gene's expression revealed a decrease in its transcripts during this period of the experiment, reaching ~10% of the control level by 24 hours. A significant negative correlation (r = -0.98) was established between the promoter methylation level and PDH-E1 gene expression. These data indicate that cytosine methylation of the promoter region may be an epigenetic mechanism involved in the regulation of PDH-E1 transcription in maize leaves under salt stress.
Zea mays, pyruvate dehydrogenase, DNA methylation, salt stress, promoter, gene expression
1. Budde, R.J., Randall, D.D. Pea leaf mitochondrial pyruvate dehydrogenase complex is inactivated in vivo in a light-dependent manner // Proc Natl Acad Sci USA. - 1990. - V. 87. - P. 673–676. doi:https://doi.org/10.1073/pnas.87.2.673.
2. Che-Othman, M.H., Millar, A.H., Taylor, N L. Connecting salt stress signalling pathways with salinity‐induced changes in mitochondrial metabolic processes in C3 plants // Plant Cell Environ. - 2017. - V. 40. - P. 2875-2905. doi:https://doi.org/10.1111/pce.13034. EDN: https://elibrary.ru/YKRBNG
3. Saha, P., Kunda, P., Biswas, A.K. I nfluence of sodium chloride on the regulation of Krebs cycle intermediates and enzymes of respiratory chain in mungbean (Vigna radiata L. Wilczek) seedlings // Plant Physiol Biochem. - 2012. - V. 60. - P. 214–222. doi:https://doi.org/10.1016/j.plaphy.2012.08.008. EDN: https://elibrary.ru/YDEOGN
4. Tovar-Mendez, A., Miernyk, J.A., Randall D.D. Regulation of pyruvate dehydrogenase complex activity in plant cells // Eur J Biochem. - 2003. - V. 270. - -P. 1043–1049. doi:https://doi.org/10.1046/j.1432-1033.2003.03469.x. EDN: https://elibrary.ru/MAHYQF
5. Plant pyruvate dehydrogenase complexes. in Alpha-Keto Acid Dehydrogenase Complexes / M.S. Patel, T.E. Roche, R.A. Harris, Eds., Basel: Birkhäuser Basel, 1996. - P. 71–92. doi:https://doi.org/10.1007/978-3-0348-8981-0_5.
6. Chinnusamy, V., Zhu, J.-K. Epigenetic regulation of stress responses in plants // Current Opinion in Plant Biology. - 2009. 1- V. 2. - P. 133–139. doi:https://doi.org/10.1016/j.pbi.2008.12.006. EDN: https://elibrary.ru/MLMHAR
7. Liu, J., He, Z. Small DNA Methylation, Big Player in Plant Abiotic Stress Responses and Memory // Front. Plant Sci. - 2020. - V. 11: 595603. doi:https://doi.org/10.3389/fpls.2020.595603. EDN: https://elibrary.ru/GSSLHK
8. Law, J.A., Jacobsen, S.E.E stablishing, maintaining and modifying DNA methylation patterns in plants and animals // Nat Rev Genet. - 2010 - V. 11. - P. 204–220. doi:https://doi.org/10.1038/nrg2719. EDN: https://elibrary.ru/MYZPDZ
9. Che-Othman, M.H., Jacoby, R.P., Millar, A.H. et al. Wheat mitochondrial respiration shifts from the tricarboxylic acid cycle to the GABA shunt under salt stress // New Phytol. - 2020. V. 225. - P. 1166-1180. doi:https://doi.org/10.1111/nph.15713. EDN: https://elibrary.ru/JNVVRJ
10. Frommer, M., McDonald, L.E., Millar, D.S., et al. A genomic sequencing protocol that yields a positive display of 5-methylcytosine residues in individual DNA strands // Proceedings of the National Academy of Sciences. 1992. - V. 89. - P. 1827–1831. doi:https://doi.org/10.1073/pnas.89.5.1827.
11. Sun, M., Yang, Z., Liu, L., et al. DNA Methylation in Plant Responses and Adaption to Abiotic
