CONSTITUTIVE OVEREXPRESSION OF THE DELLA-LIKE GENE ZPR31 FROM ZYGOPHYLLUM POTANINII MAXIM SUPPRESSES THE ANTIOXIDANT RESPONSE OF ARABIDOPSIS THALIANA UNDER MANNITOL-INDUCED OSMOTIC STRESS
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Authors
G.
Bayarmaa
Department of Biology, School of Arts and Sciences, National University of Mongolia, Ulaanbaatar 14201, Mongolia
U. Amilun
Department of Biology, School of Arts and Sciences, National University of Mongolia, Ulaanbaatar 14201, Mongolia
G.
Munkhbat
Department of Biology, School of Arts and Sciences, National University of Mongolia, Ulaanbaatar 14201, Mongolia
L.
Ser-Od
Department of Bioengineering, Mongol Koosen College of Technology, Ulaanbaatar 16081, Mongolia
J.
Bayarmaa
Department of Biology, School of Arts and Sciences, National University of Mongolia, Ulaanbaatar 14201, Mongolia
D. Oyuntsetseg
Department of Biology, School of Arts and Sciences, National University of Mongolia, Ulaanbaatar 14201, Mongolia
Abstract
ZpR31, a DELLA-like transcript whose deduced protein shares sequence similarity with GAI1, was previously identified by suppression subtractive hybridization (SSH) as downregulated in mannitol-stressed Zygophyllum potaninii. To characterise its function, transgenic Arabidopsis thaliana lines constitutively overexpressing ZpR31 (ZpR31-OE) were generated and, together with wild-type (WT) Col-0 plants, exposed to 200 mM mannitol. After 15 days of treatment, malondialdehyde (MDA) content was markedly higher in two independent ZpR31-OE lines (approximately 23–32 nmol g‑1) than in WT (approximately 16.5 nmol g‑1), indicating more extensive membrane lipid peroxidation. Superoxide dismutase (SOD) activity increased markedly in stressed WT (from approximately 410 to 515 U g‑1), whereas it declined to approximately 210 U g‑1 in both ZpR31-OE lines. Stem-loop RT-qPCR of six stress-associated microRNAs in ZpR31-OE plants relative to WT revealed transient induction of miR156, miR165, miR398 and miR827 at 24 h, a delayed miR393 peak at 48 h, and sustained miR171 repression. Because miR398 is normally downregulated under oxidative stress to permit induction of Cu/Zn-SOD genes, its induction here suggests a plausible mechanism by which ZpR31 suppresses the SOD response. These results indicate that ZpR31 acts as a negative regulator of osmotic-stress tolerance in Arabidopsis, consistent with its identification as a stress-downregulated transcript in native Z. potaninii.
Keywords
DELLA protein, ZpR31, Zygophyllum potaninii, Arabidopsis thaliana, mannitol stress, superoxide dismutase, microRNA, osmotic stress
Article Details
References
Murase K., Hirano Y., Sun T.P., Hakoshima T. Gibberellin-induced DELLA recognition by the gibberellin receptor GID1 // Nature. – 2008. – Vol. 456. – P. 459–463.
Phokas A., Coates J.C. Evolution of DELLA function and signaling in land plants // Evol. Dev. – 2021. – Vol. 23. – P. 137–154.
Peng J., Carol P., Richards D.E., King K.E., Cowling R.J., Murphy G.P., Harberd N.P. The Arabidopsis GAI gene defines a signaling pathway that negatively regulates gibberellin responses // Genes Dev. – 1997. – Vol. 11. – P. 3194–3205.
Nyambayar D., Oyuntsetseg B., Tungalag R. Regional Red List Series: Mongolian Red List and Conservation Action Plans of Plants. Vol. 9. Plants (Part 1). – London: Zoological Society of London; Ulaanbaatar: National University of Mongolia, 2011. – 192 p.
Miao D., Peng C., Ning Q., Yang Y., Cui Z., Song T., Song S., Zhang P., Jiao P., Huang W. Morphological and physiological responses to drought stress of three species of the Zygophyllum genus and a comprehensive evaluation of their drought resistance // Plants. – 2026. – Vol. 15. – P. 2317.
Achard P., Renou J.P., Berthome R., Harberd N.P., Genschik P. Plant DELLAs restrain growth and promote survival of adversity by reducing the levels of reactive oxygen species // Curr. Biol. – 2008. – Vol. 18. – P. 656–660.
Le Q.T., Truong H.A., Nguyen T.T.T., Ku K.M., Chung E.H., Lee H. SOT2/Growth-Regulating Factor 3 modulates salt tolerance by regulating gibberellin-DELLA signalling // Plant Cell Environ. – 2026. – Vol. 49. – P. 5756–5775.
Hofgen R., Willmitzer L. Storage of competent cells for Agrobacterium transformation // Nucleic Acids Res. – 1988. – Vol. 16. – P. 9877.
Clough S.J., Bent A.F. Floral dip: a simplified method for Agrobacterium-mediated transformation of Arabidopsis thaliana // Plant J. – 1998. – Vol. 16. – P. 735–743.
Murashige T., Skoog F. A revised medium for rapid growth and bio assays with tobacco tissue cultures // Physiol. Plant. – 1962. – Vol. 15. – P. 473–497.
Varkonyi-Gasic E., Wu R., Wood M., Walton E.F., Hellens R.P. Protocols: a highly sensitive RT-PCR method for detection and quantification of microRNAs // Plant Methods. – 2007. – Vol. 3. – P. 12.
Sunkar R., Kapoor A., Zhu J.K. Posttranscriptional induction of two Cu/Zn superoxide dismutase genes in Arabidopsis is mediated by downregulation of miR398 and important for oxidative stress tolerance // Plant Cell. – 2006. – Vol. 18. – P. 2051–2065.
Yu S., Galvao V.C., Zhang Y.C., Horrer D., Zhang T.Q., Hao Y.H., Feng Y.Q., Wang S., Schmid M., Wang J.W. Gibberellin regulates the Arabidopsis floral transition through miR156-targeted SQUAMOSA PROMOTER BINDING-LIKE transcription factors // Plant Cell. – 2012. – Vol. 24. – P. 3320–3332.
Carlsbecker A., Lee J.Y., Roberts C.J., Dettmer J., Lehesranta S., Zhou J., Lindgren O., Moreno-Risueno M.A., Vaten A., Thitamadee S., et al. Cell signalling by microRNA165/6 directs gene dose-dependent root cell fate // Nature. – 2010. – Vol. 465. – P. 316–321.
Sunkar R., Zhu J.K. Novel and stress-regulated microRNAs and other small RNAs from Arabidopsis // Plant Cell. – 2004. – Vol. 16. – P. 2001–2019.
Kant S., Peng M., Rothstein S.J. Genetic regulation by NLA and microRNA827 for maintaining nitrate-dependent phosphate homeostasis in Arabidopsis // PLoS Genet. – 2011. – Vol. 7. – P. e1002021.
Wang L., Mai Y.X., Zhang Y.C., Luo Q., Yang H.Q. MicroRNA171c-targeted SCL6-II, SCL6-III, and SCL6-IV genes regulate shoot branching in Arabidopsis // Mol. Plant. – 2010. – Vol. 3. – P. 794–806.