Long-chain base kinase1 affects freezing tolerance in Arabidopsis thaliana. (June 2017)

• Record Type: Journal Article
• Authors: Huang, Xiaozhen; Zhang, Yao; Zhang, Xiaoyan; Shi, Yiting
• Is Part Of: Plant science. Volume 259(2017)
• Page Start: 94
• Page End: 103
• Publication Date: 2017-06
• Subjects: ACBP6 acyl-coenzyme A-binding protein 6 -- ADS2 acyl-lipid desaturase 2 -- APX1 ascorbate peroxidase 1 -- CAT1 catalase 1 -- CBFs C-repeat/dehydration-responsive element binding factors -- CCS1 copper chaperone for superoxide dismutase 1 -- COR cold-regulated -- CRT/DRE C-repeat/drought-responsive element -- CSD copper/zinc superoxide dismutase -- DAB 3, 3′-diaminobenzidine -- DEGs differentially expressed genes -- FER1 ferritins 1 -- GUS β-glucuronidase -- LCBKs long-chain base kinases -- MS Murashige and Skoog -- NBT nitroblue tetrazolium -- PHS-P phytosphingosine-1-phosphate -- PLD phospholipase D -- ROS reactive oxygen species -- qRT-PCR quantitative reverse transcription-PCR -- SOD superoxide dismutase -- TH8 thioredoxin H8 -- WT wild type; Low temperature -- Freezing tolerance -- Long-chain base kinases -- Reactive oxygen species homeostasis -- Lipid metabolism; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2017.03.009
• Languages: English
• ISSNs: 0168-9452

Abstract

Highlights: Loss of function of LCBK1 resulted in decreased tolerance to cold stress in Arabidopsis . Overexpression of LCBK1 improved freezing tolerance in transgenic Arabidopsis plants. Transcriptome analyses suggested that LCBK1 acts in ROS homeostasis and lipid metabolism. Abstract: Long-chain base kinases (LCBKs) phosphorylate sphingolipid-derived long-chain base lipids and participate in the regulation of stress responses in plants. Here, we isolated a novel Arabidopsis thaliana mutant, lcbk1-2, which was extremely sensitive to freezing temperatures with or without cold acclimation. Physiological assays revealed that concentrations of osmolytes (proline and soluble sugars) and the activity of superoxide dismutase were significantly decreased in the lcbk1-2 mutant, compared with wild type. Also, the balance of reactive oxygen species (ROS) was disrupted in the lcbk1-2 mutant with or without cold treatment and, consistent with this, gene expression profiling analysis showed that the expression of cold-responsive ROS-scavenging genes was substantially decreased in the lcbk1-2 mutant. The expression of membrane lipid-related genes, which are linked to freezing tolerance in plants, was also impaired in the lcbk1-2 mutant. Furthermore, transgenic lines overexpressing LCBK1 showed enhanced freezing tolerance with over-accumulation of osmolytes. Collectively, our results suggested that LCBK1 functions as a novel positive regulator of freezing tolerance in Arabidopsis and may participate in the accumulation of osmolytes, the regulation of ROS homeostasis and lipid metabolism.