Resistance of Fritillaria imperialis to freezing stress through gene expression, osmotic adjustment and antioxidants
Resistance of Fritillaria imperialis to freezing stress through gene expression, osmotic adjustment and antioxidants
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DOI：
10.1038/s41598-020-63006-7
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发表时间：
2020-06-26
影响因子：
4.6
通讯作者：
Skalicky, Milan
中科院分区：
文献类型：
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作者：
Hajihashemi, Shokoofeh;Brestic, Marian;Skalicky, Milan
植物在低温胁迫下的存活依赖于其耐受机制的有效激活。冰贝母在冷冻胁迫下，Ca 2+和H2 O2沿着升高，Ca 2+信号蛋白（Ca 2+依赖性蛋白激酶，CPK）表达增加，NHX 1（Na+/H+逆向转运蛋白）、莱亚（晚期胚胎发生丰富蛋白）和P5 CS（1-吡咯啉-5-羧酸合成酶）表达上调。过量表达OsCNGC 6可使Ca ~（2+）、Na ~+和K ~+大量积累。NHX 1基因产物将Na+转运到液泡中，并增加细胞溶质K+含量，以在胁迫条件下重建离子稳态。叶片水势的降低是由于渗透调节物质和离子的大量积累。叶片的相对含水量没有变化，这可能与防止脱水的莱亚基因的过表达有关。冻结胁迫下H2 O2的大量积累激活了SOD、酚类、花青素、过氧化氢酶和抗坏血酸过氧化物酶等抗氧化系统。光合作用，抑制在冻结胁迫植物，恢复到正常水平后，冻结胁迫终止。综上所述，我们的研究结果表明，贝母有效地耐受冷冻胁迫，通过诱导信号传导机制和过表达的冷胁迫响应基因，并防止冷诱导的水分胁迫，氧化胁迫和光合损伤。
Plant survival in response to freezing stress depends on the efficient activation of tolerance mechanisms. Fritillaria imperialis exposure to freezing stress enhanced signalling molecules Ca2+ and H2O2 along with overexpression of Ca2+ signalling proteins (Ca2+ dependent protein kinases, CPK), followed by upregulation of NHX1 (Na+/H+ antiporter), LEA (late embryogenesis abundant proteins) and P5CS (1-pyrroline-5-carboxylate synthetase). Overexpression of OsCNGC6 was responsible for high accumulation Ca2+, Na+ and K+. The NHX1 gene product transported Na+ to vacuoles and increased cytosolic K+ content to re-establish ionic homeostasis under stress conditions. The reduced water potential of leaves was due to high accumulation of osmolytes and ions. No changes were observed in relative water content of leaves, which might be correlated with overexpression of the LEA gene, which protects against dehydration. High accumulation of H2O2 under freezing stress was responsible for activation of antioxidant systems involving SOD, phenols, anthocyanins, catalase and ascorbate peroxidase. Photosynthesis, suppressed in freezing-stressed plants, returned to normal levels after termination of freezing stress. Taken together, our findings suggest that Fritillaria efficiently tolerated freezing stress through induction of signalling mechanisms and overexpression of cold stress-responsive genes, and prevention of cold-induced water stress, oxidative stress and photosynthetic damage.