[Objective] The aim was to study the cDNA cloning of SMAT gene from Chimonanthus praecox and its expression. [Method] A novel cDNA was cloned by PT-PCR using the total RNA as template, and amplified to the desirable s...[Objective] The aim was to study the cDNA cloning of SMAT gene from Chimonanthus praecox and its expression. [Method] A novel cDNA was cloned by PT-PCR using the total RNA as template, and amplified to the desirable size. The RT-PCR products were reclaimed and transformed into E. coli DH 5o together with the PMD18-T vector after ligating by T-A cloning. Identified by colony PCR and EcoRI and Notl digestion, the recombinant plasmid with target gene was screened out and conducted the sequence analysis. [Result] Results of the sequence analysis showed that the ORF fragment of the SAMT cDNA was successfully cloned from Chimonanthus praecox gene, with the length of 1 196 bp and encoding 380 amino acids fragment which shared 99.2% homology to that of previously reported SAMT cDNA from Chimonanthus praecox (ABU88887). The SAMT cDNA fragment was sub-cloned into the prokaryotic expression vector PGEX1-4T-1, and the obtained re- combinant plasmid was named PGSAMT. After inducting by 0.01mol/L IPTG, the re- sult of the SDS-PAGE analysis showed that the molecular weight of the fusion ex- pression SAMT protein was about 66 kDa, which was close to the predicted fusion protein derived from the 26 kDa GST band and 42.3 kDa SAMT gene of Chimo- nanthus praecox encoded protein. [Conclusion] This study successfully cloned and expressed the SAMT gene of Chimonanthus praecox.展开更多
Chimonanthus praecox is an important ornamental plant and cut flower material in China.It blooms in the freezing winter and its flower emits charming fragrance.However,in different region the flowering time is variabl...Chimonanthus praecox is an important ornamental plant and cut flower material in China.It blooms in the freezing winter and its flower emits charming fragrance.However,in different region the flowering time is variable.In order to understand the flowering mechanism of Ch.praecox in the winter,we studied the flower bud differentiation in Spring City-Kunming using paraffin sectioning method in the present study.Meanwhile we compared the differentiation process difference from different regions.It was found that the temperature is the key factor for its flower bud differentiation and blossom of Ch.praecox.In the process of bud differentiation,the temperature 20℃was the optimum for inducing changes from vegetative axillary buds to reproductive buds and subsequent morphological differentiation in Ch.praecox.Furthermore in the first three differentiation periods—tepal primordial stage,staminal primordial stage and pistil primordial stage,Kunming took the shortest time to finish the process due to very rapid temperature rise to 20℃,whereas,in Zhengzhou the time for these differentiations was the longest,which may be caused by the slow temperature rise.After May,the high temperature stress forced the flower buds into the first long dormant period in all regions except Kunming.In Kunming,the average temperature was only 20–25℃,so the flower bud continued to differentiate.In all regions,Kunming is the first to complete whole flower bud differentiation even on the early August,and started the second dormancy very early but very long.In the other regions,the plants went through a shorter dormancy and the low temperature broke the dormancy rapidly.Contrarily the plants of Kunming spent a longer period for the low temperature.Thus,the low temperature less than 10℃is a key factor to breaking the second dormancy.Surely the regular effects of temperature on flower bud differentiation and blossom is very helpful for florescence regulation of Ch.praecox.展开更多
Vernalization is a process of acquiring or accelerating the flowering ability by prolonged cold exposure.VERNALIZATION INSENSITIVE3(VIN3)is induced by chilling and is extremely important for the vernalization response...Vernalization is a process of acquiring or accelerating the flowering ability by prolonged cold exposure.VERNALIZATION INSENSITIVE3(VIN3)is induced by chilling and is extremely important for the vernalization response in Arabidopsis thaliana.However,the issue of the induction of the VIN3-LIKE genes in wintersweet(Chimonanthus praecox)has been largely neglected.In the present study,we explored the molecular regulation of the PHD type finger protein-encoding gene CpVIL2 in relation to the growth and development of wintersweet in Arabidopsis.In wintersweet,quantitative real-time PCR(qRT-PCR)analysis showed that the relative expression of CpVIL2-As2i(intron-retained alternatively spliced in the second intron)was extremely higher in the pistils than in the other tissues.And the relative CpVIL2-As2i expression in flower buds(FBs)treated at 8°C was higher than that of FBs in December,2016 under natural conditions,which was not detected in non-flowering FBs at 16°C.In Arabidopsis,the expression patterns of the CpVIL2-As2i gene were detected at first in CpVIL2-As2i pro::GUS(β-glucuronidase)lines,with predominantly higher expression in flowers and inflorescence.Meanwhile,the hormone-induced expression profiles of the CpVIL2-As2i promoter were confirmed using exogenous induction by abscisic acid(ABA)and indole acetic acid(IAA)phytohormones,where the GUS enzyme activity obviously decreased compared with that of control.In comparison with Arabidopsis/Col-0,early flowering was detected in ectopic 35S::CpVIL2-As2i lines.Overall,these results demonstrated the function of the CpVIL2-As2i gene,at the same time,provided us with new insights into the molecular mechanisms of early flowering and complex regulatory networks of vernalization in wintersweet.展开更多
Objective] To analyze the aroma constituents of essential oils from Chi-monanthus praecox. [Method] Extracted by microwave-assisted hydrodistil ation (MAHD), aroma constituents of essential oils of Chimonanthus prae...Objective] To analyze the aroma constituents of essential oils from Chi-monanthus praecox. [Method] Extracted by microwave-assisted hydrodistil ation (MAHD), aroma constituents of essential oils of Chimonanthus praecox flowers were analyzed by gas chromatography-mass spectrometry (GC-MS). Normalization method was used to determine the constituents quantitatively. [Result] Total y 27 compounds were identified, accounting for 98.85% of total amounts. The main aroma con-stituents are terpenes, aldehydes, esters, alcohols and hydrocarbons. Main compo-nents with relative percentage over 5% are germacrene D (25.62%), bornyl acetate (16.71%), caryophyl ene (10.51%), cis-α-ocimene (5.18%), γ-elemene (8.05%), β-linalool (5.01%), 1-ethenyl-1-methyl-2,4-bis (1-methylethenyl)-cyclohexane (7.18%) and 2,3,4,4α,5,6-hexahydro-1,4αdimethyl-7-(1-methylethyl)-naphthalene (5.20%). [Conclu-sion] The study provided a theoretical reference for the development and utilization of Chimonanthus praecox resources.展开更多
The complex of calcineurin B-like protein(CBL)and CBL-interacting protein kinase(CIPK)serves as key components in calcium-sensing,orchestrating various signals crucial for plant growth,development,and responses to bio...The complex of calcineurin B-like protein(CBL)and CBL-interacting protein kinase(CIPK)serves as key components in calcium-sensing,orchestrating various signals crucial for plant growth,development,and responses to biotic and abiotic stresses.However,the mechanism underlying the response of this module to cold stress and its role in flower development in wintersweet(Chimonanthus praecox)remains unclear.Through expression pattern analysis,calcium ion(Ca^(2+))concentration assays,correlation analysis,and linear regression analysis,we found that the[Ca^(2+)],along with CpCBL8 and CpCIPK9 expression levels in wintersweet flower buds(FBs),significantly decreased during the initial flowering stage when the chilling requirement reached 570 chill units(CU).Notably,there was a significant positive correlation between[Ca^(2+)]and CpCBL8 expression.Ca^(2+)increased the expression of Cp CBL8 and CpCIPK9 in FBs,causing a significant delay in the flowering of wintersweet.Furthermore,the function of CpCBL8 was studied using heterologous transformation.Overexpression of CpCBL8 significantly delayed flowering time and significantly reduced cold tolerance and altered the expression pattern of endogenous genes related to low-temperature stress and flower development in transgenic Arabidopsis thaliana.Additionally,transcriptome analysis of chilling-induced dormancy breaking and flower bud enlargement revealed that CpCBL8 and CpCIPK9 were negatively regulated by cold,and the expression pattern of endogenous genes related to flower development and cold stress in wintersweet were similar to that of in A.thaliana.Moreover,protein-protein interaction(PPI)analysis revealed that CpCBL8 and CpCIPK9 interacted in the plasma membrane and nucleus.On the basis of these findings,we speculated that the CpCBL8-CpCIPK9 module plays a crucial role in regulating responses to cold stress and flower development in wintersweet.This study elucidated molecular mechanisms through which the downregulation of the Ca^(2+)-induced CpCBL8-CpCIPK9 module results in dormancy breaking and enhances cold tolerance.This study provides valuable insights for the cultivation of new varieties of wintersweet with increased ornamental value and enhanced cold stress tolerance.展开更多
Wintersweet(Chimonanthus praecox),a well-known fragrant flowering shrub,is extensively planted for ornamental purpose and production of floral essential oil.Although the tepal color of wintersweet varieties exhibits t...Wintersweet(Chimonanthus praecox),a well-known fragrant flowering shrub,is extensively planted for ornamental purpose and production of floral essential oil.Although the tepal color of wintersweet varieties exhibits the most remarkable diversity,variations in the floral scent traits are also noticeable across different cultivars.In this study,the floral volatile organic compounds(VOCs)in three wintersweet cultivars,‘Yanlingsuxin’,‘Yuxiang’,and‘Hongyun’were detected via GC-MS coupled with OAV.The distinct floral aromas of the three cultivars were primarily attributed to benzyl alcohol(abundant in‘Yuxiang’),linalool(abundant in‘Yanlingsuxin’),(-)-γ-cadinene and eugenol(abundant in‘Hongyun’).Integrated analyses of metabolome and transcriptome showed that an R2R3-MYB transcription factor gene,CpODO1,potentially have a crucial regulatory function in controlling the production of multiple aroma compounds.Overexpression of CpODO1 can enhance the production of benzyl alcohol in transgenic tobacco flowers.Analysis of DAP-seq data,EMSA and dual-luciferase assay revealed that CpODO1 predominantly regulate the expression of CpCYP71,a cytochrome P450 gene encoding a key enzyme in the production of benzyl alcohol,and the transcriptional regulation of CpODO1 is driven by CpEOBII.The identification of polymorphisms in the MYB binding cis-motifs of CpCYP71 and CpODO1 promoters revealed the regulatory mechanism underlying the varied synthesis of benzyl alcohol in three wintersweet cultivars.This study provides new anchor points for floral scent quality improvement breeding of wintersweet,and the profusion of wintersweet germplasm can serve as a material basis for developing various aroma products.展开更多
文摘[Objective] The aim was to study the cDNA cloning of SMAT gene from Chimonanthus praecox and its expression. [Method] A novel cDNA was cloned by PT-PCR using the total RNA as template, and amplified to the desirable size. The RT-PCR products were reclaimed and transformed into E. coli DH 5o together with the PMD18-T vector after ligating by T-A cloning. Identified by colony PCR and EcoRI and Notl digestion, the recombinant plasmid with target gene was screened out and conducted the sequence analysis. [Result] Results of the sequence analysis showed that the ORF fragment of the SAMT cDNA was successfully cloned from Chimonanthus praecox gene, with the length of 1 196 bp and encoding 380 amino acids fragment which shared 99.2% homology to that of previously reported SAMT cDNA from Chimonanthus praecox (ABU88887). The SAMT cDNA fragment was sub-cloned into the prokaryotic expression vector PGEX1-4T-1, and the obtained re- combinant plasmid was named PGSAMT. After inducting by 0.01mol/L IPTG, the re- sult of the SDS-PAGE analysis showed that the molecular weight of the fusion ex- pression SAMT protein was about 66 kDa, which was close to the predicted fusion protein derived from the 26 kDa GST band and 42.3 kDa SAMT gene of Chimo- nanthus praecox encoded protein. [Conclusion] This study successfully cloned and expressed the SAMT gene of Chimonanthus praecox.
基金funded by Talents Introduction Plan of Yunnan Province-"High-End Foreign Experts"Program(Grant No.000019)。
文摘Chimonanthus praecox is an important ornamental plant and cut flower material in China.It blooms in the freezing winter and its flower emits charming fragrance.However,in different region the flowering time is variable.In order to understand the flowering mechanism of Ch.praecox in the winter,we studied the flower bud differentiation in Spring City-Kunming using paraffin sectioning method in the present study.Meanwhile we compared the differentiation process difference from different regions.It was found that the temperature is the key factor for its flower bud differentiation and blossom of Ch.praecox.In the process of bud differentiation,the temperature 20℃was the optimum for inducing changes from vegetative axillary buds to reproductive buds and subsequent morphological differentiation in Ch.praecox.Furthermore in the first three differentiation periods—tepal primordial stage,staminal primordial stage and pistil primordial stage,Kunming took the shortest time to finish the process due to very rapid temperature rise to 20℃,whereas,in Zhengzhou the time for these differentiations was the longest,which may be caused by the slow temperature rise.After May,the high temperature stress forced the flower buds into the first long dormant period in all regions except Kunming.In Kunming,the average temperature was only 20–25℃,so the flower bud continued to differentiate.In all regions,Kunming is the first to complete whole flower bud differentiation even on the early August,and started the second dormancy very early but very long.In the other regions,the plants went through a shorter dormancy and the low temperature broke the dormancy rapidly.Contrarily the plants of Kunming spent a longer period for the low temperature.Thus,the low temperature less than 10℃is a key factor to breaking the second dormancy.Surely the regular effects of temperature on flower bud differentiation and blossom is very helpful for florescence regulation of Ch.praecox.
基金supported by the Grants from the Natural Science Foundation of Chongqing(No.cstc2020jcyj-msxmX1014)Fundamental Research Funds for the Central Universities(No.XDJK2020B059)National Natural Science Foundation of China(Grant No.31971711).
文摘Vernalization is a process of acquiring or accelerating the flowering ability by prolonged cold exposure.VERNALIZATION INSENSITIVE3(VIN3)is induced by chilling and is extremely important for the vernalization response in Arabidopsis thaliana.However,the issue of the induction of the VIN3-LIKE genes in wintersweet(Chimonanthus praecox)has been largely neglected.In the present study,we explored the molecular regulation of the PHD type finger protein-encoding gene CpVIL2 in relation to the growth and development of wintersweet in Arabidopsis.In wintersweet,quantitative real-time PCR(qRT-PCR)analysis showed that the relative expression of CpVIL2-As2i(intron-retained alternatively spliced in the second intron)was extremely higher in the pistils than in the other tissues.And the relative CpVIL2-As2i expression in flower buds(FBs)treated at 8°C was higher than that of FBs in December,2016 under natural conditions,which was not detected in non-flowering FBs at 16°C.In Arabidopsis,the expression patterns of the CpVIL2-As2i gene were detected at first in CpVIL2-As2i pro::GUS(β-glucuronidase)lines,with predominantly higher expression in flowers and inflorescence.Meanwhile,the hormone-induced expression profiles of the CpVIL2-As2i promoter were confirmed using exogenous induction by abscisic acid(ABA)and indole acetic acid(IAA)phytohormones,where the GUS enzyme activity obviously decreased compared with that of control.In comparison with Arabidopsis/Col-0,early flowering was detected in ectopic 35S::CpVIL2-As2i lines.Overall,these results demonstrated the function of the CpVIL2-As2i gene,at the same time,provided us with new insights into the molecular mechanisms of early flowering and complex regulatory networks of vernalization in wintersweet.
基金Supported by the Research Fund from Guizhou Academy of Agricultural Science(2013009)Innovation Capacity Platform Construction Project of Guizhou Science and Technology Department(20104008)~~
文摘Objective] To analyze the aroma constituents of essential oils from Chi-monanthus praecox. [Method] Extracted by microwave-assisted hydrodistil ation (MAHD), aroma constituents of essential oils of Chimonanthus praecox flowers were analyzed by gas chromatography-mass spectrometry (GC-MS). Normalization method was used to determine the constituents quantitatively. [Result] Total y 27 compounds were identified, accounting for 98.85% of total amounts. The main aroma con-stituents are terpenes, aldehydes, esters, alcohols and hydrocarbons. Main compo-nents with relative percentage over 5% are germacrene D (25.62%), bornyl acetate (16.71%), caryophyl ene (10.51%), cis-α-ocimene (5.18%), γ-elemene (8.05%), β-linalool (5.01%), 1-ethenyl-1-methyl-2,4-bis (1-methylethenyl)-cyclohexane (7.18%) and 2,3,4,4α,5,6-hexahydro-1,4αdimethyl-7-(1-methylethyl)-naphthalene (5.20%). [Conclu-sion] The study provided a theoretical reference for the development and utilization of Chimonanthus praecox resources.
基金funded by the Natural Science Foundation of Chongqing(CSTB2023NSCQ-MSX0236)Fundamental Research Funds for the Central Universities(SWU-XDJH202308)Earmarked Funds for the China Agriculture Research System(CARS-26)。
文摘The complex of calcineurin B-like protein(CBL)and CBL-interacting protein kinase(CIPK)serves as key components in calcium-sensing,orchestrating various signals crucial for plant growth,development,and responses to biotic and abiotic stresses.However,the mechanism underlying the response of this module to cold stress and its role in flower development in wintersweet(Chimonanthus praecox)remains unclear.Through expression pattern analysis,calcium ion(Ca^(2+))concentration assays,correlation analysis,and linear regression analysis,we found that the[Ca^(2+)],along with CpCBL8 and CpCIPK9 expression levels in wintersweet flower buds(FBs),significantly decreased during the initial flowering stage when the chilling requirement reached 570 chill units(CU).Notably,there was a significant positive correlation between[Ca^(2+)]and CpCBL8 expression.Ca^(2+)increased the expression of Cp CBL8 and CpCIPK9 in FBs,causing a significant delay in the flowering of wintersweet.Furthermore,the function of CpCBL8 was studied using heterologous transformation.Overexpression of CpCBL8 significantly delayed flowering time and significantly reduced cold tolerance and altered the expression pattern of endogenous genes related to low-temperature stress and flower development in transgenic Arabidopsis thaliana.Additionally,transcriptome analysis of chilling-induced dormancy breaking and flower bud enlargement revealed that CpCBL8 and CpCIPK9 were negatively regulated by cold,and the expression pattern of endogenous genes related to flower development and cold stress in wintersweet were similar to that of in A.thaliana.Moreover,protein-protein interaction(PPI)analysis revealed that CpCBL8 and CpCIPK9 interacted in the plasma membrane and nucleus.On the basis of these findings,we speculated that the CpCBL8-CpCIPK9 module plays a crucial role in regulating responses to cold stress and flower development in wintersweet.This study elucidated molecular mechanisms through which the downregulation of the Ca^(2+)-induced CpCBL8-CpCIPK9 module results in dormancy breaking and enhances cold tolerance.This study provides valuable insights for the cultivation of new varieties of wintersweet with increased ornamental value and enhanced cold stress tolerance.
基金supported by the China National Natural Science Foundation(Grant No.32102417)Henan Key R&D Project,China(Grant No.221111110700)+1 种基金Henan Academy of Agricultural Sciences“Innovation and Utilization of Characteristic Flowers and Trees Germplasm”Team Project(Grant Nos.2023TD35 and2024TD26)Hunan Provincial Natural Science Foundation of China(Grant No.2024JJ6711),Natural Science Foundation of Guangxi(Grant No.2024JJB130300)。
文摘Wintersweet(Chimonanthus praecox),a well-known fragrant flowering shrub,is extensively planted for ornamental purpose and production of floral essential oil.Although the tepal color of wintersweet varieties exhibits the most remarkable diversity,variations in the floral scent traits are also noticeable across different cultivars.In this study,the floral volatile organic compounds(VOCs)in three wintersweet cultivars,‘Yanlingsuxin’,‘Yuxiang’,and‘Hongyun’were detected via GC-MS coupled with OAV.The distinct floral aromas of the three cultivars were primarily attributed to benzyl alcohol(abundant in‘Yuxiang’),linalool(abundant in‘Yanlingsuxin’),(-)-γ-cadinene and eugenol(abundant in‘Hongyun’).Integrated analyses of metabolome and transcriptome showed that an R2R3-MYB transcription factor gene,CpODO1,potentially have a crucial regulatory function in controlling the production of multiple aroma compounds.Overexpression of CpODO1 can enhance the production of benzyl alcohol in transgenic tobacco flowers.Analysis of DAP-seq data,EMSA and dual-luciferase assay revealed that CpODO1 predominantly regulate the expression of CpCYP71,a cytochrome P450 gene encoding a key enzyme in the production of benzyl alcohol,and the transcriptional regulation of CpODO1 is driven by CpEOBII.The identification of polymorphisms in the MYB binding cis-motifs of CpCYP71 and CpODO1 promoters revealed the regulatory mechanism underlying the varied synthesis of benzyl alcohol in three wintersweet cultivars.This study provides new anchor points for floral scent quality improvement breeding of wintersweet,and the profusion of wintersweet germplasm can serve as a material basis for developing various aroma products.