[Objective] The aim was to clone CBF3 gene from Arabidopsis thaliana and construct plant expression vector pCAMBIA1301-Rd29A-CBF3.[Method] CBF3 gene and stress-inducible promoter Rd29A were amplified from the genomic ...[Objective] The aim was to clone CBF3 gene from Arabidopsis thaliana and construct plant expression vector pCAMBIA1301-Rd29A-CBF3.[Method] CBF3 gene and stress-inducible promoter Rd29A were amplified from the genomic DNA of A.thaliana for the construction of plant expression vector.[Result] Sequencing results showed that the cloned CBF3 gene had 750 bp,and showed 100% identity with the sequence published on GenBank.The promoter Rd29A had 1 425 bp,and showed 100% identity with the sequence published on GenBank.[Conclusion] Based on the binary vector pCAMBIA1301,the plant expression vector pCAMBIA1301-Rd29A-CBF3 was constructed successfully,which could materially improve the salt resistance,drought-tolerance,cold resistance of plants.展开更多
Plant growth and development are significantly hampered in saline environments,limiting agricultural productivity.Thus,it is crucial to unravel the mechanism underlying plant responses to salt stress.β-1,4-Galactan(g...Plant growth and development are significantly hampered in saline environments,limiting agricultural productivity.Thus,it is crucial to unravel the mechanism underlying plant responses to salt stress.β-1,4-Galactan(galactan),which forms the side chains of pectic rhamnogalacturonan I,enhances plant sensitivity to high-salt stress.Galactan is synthesized by GALACTAN SYNTHASE1(GALS1).We previously showed that Na Cl relieves the direct suppression of GALS1 transcription by the transcription factors BPC1 and BPC2 to induce the excess accumulation of galactan in Arabidopsis(Arabidopsis thaliana).However,how plants adapt to this unfavorable environment remains unclear.Here,we determined that the transcription factors CBF1,CBF2,and CBF3 directly interact with the GALS1 promoter and repress its expression,leading to reduced galactan accumulation and enhanced salt tolerance.Salt stress enhances the binding of CBF1/CBF2/CBF3 to the GALS1 promoter by inducing CBF1/CBF2/CBF3 transcription and accumulation.Genetic analysis suggested that CBF1/CBF2/CBF3 function upstream of GALS1 to modulate salt-induced galactan biosynthesis and the salt response.CBF1/CBF2/CBF3 and BPC1/BPC2 function in parallel to regulate GALS1 expression,thereby modulating the salt response.Our results reveal a mechanism in which salt-activated CBF1/CBF2/CBF3 inhibit BPC1/BPC2-regulated GALS1 expression to alleviate galactan-induced salt hypersensitivity,providing an activation/deactivation fine-tune mechanism for dynamic regulation of GALS1 expression under salt stress in Arabidopsis.展开更多
基金Supported by Cultivation for New Varieties of Genetically Modified Organisms Technology Projects(2008ZX08001-004)Key Projects of Nanjing Xiaozhuang University(2007NXY01)Natural ScienceFoundation for Jiangsu Province Universities(08KJD180011)~~
文摘[Objective] The aim was to clone CBF3 gene from Arabidopsis thaliana and construct plant expression vector pCAMBIA1301-Rd29A-CBF3.[Method] CBF3 gene and stress-inducible promoter Rd29A were amplified from the genomic DNA of A.thaliana for the construction of plant expression vector.[Result] Sequencing results showed that the cloned CBF3 gene had 750 bp,and showed 100% identity with the sequence published on GenBank.The promoter Rd29A had 1 425 bp,and showed 100% identity with the sequence published on GenBank.[Conclusion] Based on the binary vector pCAMBIA1301,the plant expression vector pCAMBIA1301-Rd29A-CBF3 was constructed successfully,which could materially improve the salt resistance,drought-tolerance,cold resistance of plants.
基金supported by grants from the National Natural Science Foundation of China(32001445)。
文摘Plant growth and development are significantly hampered in saline environments,limiting agricultural productivity.Thus,it is crucial to unravel the mechanism underlying plant responses to salt stress.β-1,4-Galactan(galactan),which forms the side chains of pectic rhamnogalacturonan I,enhances plant sensitivity to high-salt stress.Galactan is synthesized by GALACTAN SYNTHASE1(GALS1).We previously showed that Na Cl relieves the direct suppression of GALS1 transcription by the transcription factors BPC1 and BPC2 to induce the excess accumulation of galactan in Arabidopsis(Arabidopsis thaliana).However,how plants adapt to this unfavorable environment remains unclear.Here,we determined that the transcription factors CBF1,CBF2,and CBF3 directly interact with the GALS1 promoter and repress its expression,leading to reduced galactan accumulation and enhanced salt tolerance.Salt stress enhances the binding of CBF1/CBF2/CBF3 to the GALS1 promoter by inducing CBF1/CBF2/CBF3 transcription and accumulation.Genetic analysis suggested that CBF1/CBF2/CBF3 function upstream of GALS1 to modulate salt-induced galactan biosynthesis and the salt response.CBF1/CBF2/CBF3 and BPC1/BPC2 function in parallel to regulate GALS1 expression,thereby modulating the salt response.Our results reveal a mechanism in which salt-activated CBF1/CBF2/CBF3 inhibit BPC1/BPC2-regulated GALS1 expression to alleviate galactan-induced salt hypersensitivity,providing an activation/deactivation fine-tune mechanism for dynamic regulation of GALS1 expression under salt stress in Arabidopsis.
