Lu Lu1,2, Xinying Chen1, Pengkai Wang1, Ye Lu1, Jingbo Zhang3, Xiuyan Yang4, Tielong Cheng1, Jisen Shi1, Jinhui Chen5. 1. Key Laboratory of Forest Genetics & Biotechnology of Ministry of Education, Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, 210037, China. 2. College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, China. 3. Experimental Center of Desert Forestry, Chinese Academy of Forestry, Dengkou, Inner Mongolia, China. 4. Research Center of Saline and Alkali Land of National Forestry and Grassland Administration, China Academy of Forestry, Beijing, 100091, China. 5. Key Laboratory of Forest Genetics & Biotechnology of Ministry of Education, Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, 210037, China. chenjh@njfu.edu.cn.
Abstract
BACKGROUND: The CIPKs are a group of plant-specific Ser/Thr protein kinases acting in response to calcium signaling, which plays an important role in the physiological and developmental adaptation of plants to adverse environments. However, the functions of halophyte-derived CIPKs are still poorly understood, that limits a potential application of CIPKs from halophytes for improving the tolerance of glycophytes to abiotic stresses. RESULTS: In this study, we characterized the NtCIPK11 gene from the halophyte Nitraria tangutorum and subsequently analyzed its role in salt and drought stress tolerance, using Arabidopsis as a transgenic model system. NtCIPK11 expression was upregulated in N. tangutorum root, stem and blade tissues after salt or drought treatment. Overexpressing NtCIPK11 in Arabidopsis improved seed germination on medium containing different levels of NaCl. Moreover, the transgenic plants grew more vigorously under salt stress and developed longer roots under salt or drought conditions than the WT plants. Furthermore, NtCIPK11 overexpression altered the transcription of genes encoding key enzymes involved in proline metabolism in Arabidopsis exposed to salinity, however, which genes showed a relatively weak expression in the transgenic Arabidopsis undergoing mannitol treatment, a situation that mimics drought stress. Besides, the proline significantly accumulated in NtCIPK11-overexpressing plants compared with WT under NaCl treatment, but that was not observed in the transgenic plants under drought stress caused by mannitol application. CONCLUSIONS: We conclude that NtCIPK11 promotes plant growth and mitigates damage associated with salt stress by regulating the expression of genes controlling proline accumulation. These results extend our understanding on the function of halophyte-derived CIPK genes and suggest that NtCIPK11 can serve as a candidate gene for improving the salt and drought tolerance of glycophytes through genetic engineering.
BACKGROUND: The CIPKs are a group of plant-specific Ser/Thr protein kinases acting in response to calcium signaling, which plays an important role in the physiological and developmental adaptation of plants to adverse environments. However, the functions of halophyte-derived CIPKs are still poorly understood, that limits a potential application of CIPKs from halophytes for improving the tolerance of glycophytes to abiotic stresses. RESULTS: In this study, we characterized the NtCIPK11 gene from the halophyte Nitraria tangutorum and subsequently analyzed its role in salt and drought stress tolerance, using Arabidopsis as a transgenic model system. NtCIPK11 expression was upregulated in N. tangutorum root, stem and blade tissues after salt or drought treatment. Overexpressing NtCIPK11 in Arabidopsis improved seed germination on medium containing different levels of NaCl. Moreover, the transgenic plants grew more vigorously under salt stress and developed longer roots under salt or drought conditions than the WT plants. Furthermore, NtCIPK11 overexpression altered the transcription of genes encoding key enzymes involved in proline metabolism in Arabidopsis exposed to salinity, however, which genes showed a relatively weak expression in the transgenic Arabidopsis undergoing mannitol treatment, a situation that mimics drought stress. Besides, the proline significantly accumulated in NtCIPK11-overexpressing plants compared with WT under NaCl treatment, but that was not observed in the transgenic plants under drought stress caused by mannitol application. CONCLUSIONS: We conclude that NtCIPK11 promotes plant growth and mitigates damage associated with salt stress by regulating the expression of genes controlling proline accumulation. These results extend our understanding on the function of halophyte-derived CIPK genes and suggest that NtCIPK11 can serve as a candidate gene for improving the salt and drought tolerance of glycophytes through genetic engineering.
Entities:
Keywords:
CIPK11; Drought stress; Halophyte; Nitraria tangutorum; Salt stress
Authors: Rafael de Souza Miranda; Juan Carlos Alvarez-Pizarro; José Hélio Costa; Stelamaris de Oliveira Paula; José Tarquinio Prisco; Enéas Gomes-Filho Journal: Plant Signal Behav Date: 2017-08-14