| 摘要: |
| 【目的】研究盐碱胁迫对转羊草钙依赖蛋白激酶基因（Lc-CDPK）水稻根、叶片抗氧化酶活性及基因表达的影响。【方法】以转Lc-CDPK水稻为试验材料，通过qRT-PCR技术，测定根、叶片中Lc-CDPK基因的表达，确定该基因表达最高时的盐碱胁迫条件，以此条件处理幼苗，并以非转基因水稻为对照，分别测定其根、叶片中甜菜碱、脯氨酸、甘露醇、山梨醇、蔗糖等渗透调节物质含量和超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）、谷胱甘肽还原酶（GR）、谷胱甘肽过氧化物酶（GPX）等抗氧化酶活性及相关基因的表达。【结果】200 mmol/L NaCl-Na2CO3胁迫24 h时，转基因水稻根和叶片中Lc-CDPK基因表达的综合水平最高，此时转基因水稻和非转基因水稻(对照)的渗透调节物质含量和抗氧化酶活性有显著差异，转基因水稻根中脯氨酸、甘露醇和山梨醇含量分别较对照增加116.0%，88.9%和115.4%（P＜0.01），GR活性较对照提高9.6%（P＜0.05）；叶片中脯氨酸含量较对照增加129.2%（P＜0.01），CAT、POD、GR和GPX活性分别较对照提高52.1%，27.5%，163.5%和46.7%。叶片中抗氧化酶基因相对表达显著增强，CAT、GPX基因相对表达量分别是对照的3.96和2.73倍（P＜0.01），根中仅GR基因相对表达增强，为对照的1.6倍（P＜0.01）。相关分析表明，根、叶片抗氧化酶活性与其基因相对表达量呈正相关。【结论】推测Lc-CDPK基因可能参与调控盐碱胁迫过程，能增强植株渗透调节物质的合成能力及抗氧化酶活性，提高水稻对盐碱胁迫的耐受性。 |
| 关键词: 水稻 Lc-CDPK基因 盐碱胁迫 渗透调节物质 抗氧化酶 基因表达 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金项目(31171459)；吉林省自然科学基金项目（主题科学家专项）（20180101026）；吉林省教育厅“十三五”科学技术项目(JJKH20170307KJS) |
|
| Effects of saline-alkali stress on activities and gene expression of antioxidant enzymes of transgenic Lc-CDPK rice |
|
CHEN Zhanyu,FEI Xiaoyu,SUN Fan,et al
|
| Abstract: |
| 【Objective】The effects of saline-alkali stress on antioxidant enzyme activities and gene expression in roots and leaves of transgenic rice with Leymus chinensis Ca2+ dependent protein kinase gene (Lc-CDPK) were analyzed.【Method】Using qRT-PCR,the most appropriate treatment conditions for highest gene expression in roots and leaves of transgenic rice were clarified.After saline-alkali stress treatments,the contents of betaine,proline,mannitol,sorbitol and sucrose were measured and the activities and gene expression of antioxidant enzymes including superoxide dismutase (SOD),peroxidase (POD),catalase (CAT),glutathione reductase (GR) and glutathione peroxidase (GPX) in seedlings were assayed.【Result】The expression levels of Lc-CDPK in roots and leaves of transgenic rice were the highest 24 h after treatment by 200 mmol/L NaCl-Na2CO3.Under this stress condition,difference between transgenic rice and no transgenic rice (CK) was significant in contents of osmotic regulation solutes and activities of antioxidant enzymes.The contents of proline, mannitol and sorbitol were increased by 116.0%,88.9% and 115.4% comparing CK （P＜0.01）,and GR activity was increased by 9.6% （P＜0.05）.The proline content in leaves was increased by 129.2% （P＜0.01）,and the activities of CAT,POD,GR and GPX was 52.1%,27.5%,163.5% and 46.7% higher than those of CK in leaves.The relative expression levels and antioxidant enzyme activities in leaves of the transgenic rice were enhanced,and relative expression levels of CAT,GPX of transgenic rice were 3.96 and 2.73 times of CK (P<0.01).Relative expression levels of GR were only increased in roots,which was 1.6 times of CK (P<0.01).Correlation analysis indicated that the gene expression was positively correlated with activities of antioxidant enzymes in roots and leaves.【Conclusion】This study indicated that the Lc-CDPK involved in regulation of saline alkali stress response,which increased the accumulation of osmotic regulators and activities of antioxidant enzymes,and improved the tolerance to saline alkali stress. |
| Key words: rice Lc-CDPK gene saline-alkali stress osmotic regulation solutes antioxidant enzyme gene expression |
