The plant-specific NAC(NAM,ATAF1 /2,CUC2) transcription factors play important roles in stess responses and devlopment in plants,but little was known about NACs in tea plants(Camellia sinensis).In this study,a fulllen...The plant-specific NAC(NAM,ATAF1 /2,CUC2) transcription factors play important roles in stess responses and devlopment in plants,but little was known about NACs in tea plants(Camellia sinensis).In this study,a fulllength cDNA sequence(CsNAC) was isolated by suppressive subtractive hybridization(SSH) in Ectropic oblique feeding-induced tea plants.Gene sequence analysis showed that the putative protein of CsNAC contained a conserved NAC domain,which is the typical characteristic of NAC transcription factors.qRT-PCR analysis revealed that CsNAC was suppressed by Ectropis oblique feeding and mechanical damage.Treatment of defence-related homones methyl jasmonate(MeJA) decreased the transcript abudance of CsNAC and salicylic acid(SA) could induce the expression of CsNAC.The transcript levels of CsNAC was down-regulated after applying abscisic acid(ABA) and the expression patterns of CsNAC were different by drought or cold stress.Subcellular localization analysis revealed that CsNAC protein was localized in the nucleus.These results suggested that CsNAC may play a role in defense against insects and adaptation to abiotic stresses.展开更多
Terpenoids play important roles in productivity and product quality in tea(Camellia sinensis),not only because volatile terpenoids contribute significantly to the aroma of teas,but terpenoid-derived light harvesting p...Terpenoids play important roles in productivity and product quality in tea(Camellia sinensis),not only because volatile terpenoids contribute significantly to the aroma of teas,but terpenoid-derived light harvesting pigments and phytohormones such as strigolactones implement photosynthesis and branching in plants.All terpenoids are derived from isopentenyl diphosphate(IPP),dimethylallyl diphosphate(DMAPP) produced by methyl-erythritol-phosphate(MEP) and mevalonate(MVA) pathways,the early steps of isoprenoid biosynthesis.For the purpose to determine key genes in the MEP and MVA pathways in C.sinensis,five genes with complete coding sequence and three with partial sequence were obtained based on previously attained transcriptome data and polymerase chain reaction approach in this study.In silico analyses suggested that the five genes with full coding sequence individually encoded acetyl-CoA C-acetyltransferase(CsAACT),3-hydroxy-3-methylglutaryl-CoA synthase(CsHMGS),4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol kinase(CsCMK),1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate synthase(CsHDS),and farnesyl pyrophosphate synthase(CsFPS).Additionally,studies on metabolite-mediated gene expression were performed using tea cell suspensions and leaf-disc cultures.Our data showed that the addition of acetyl-CoA increased the transcript level of CsAACT and CsHMGS by 1.5- and 3-fold,respectively.The addition of deoxy-D-xylulose 5-phosphate(DXP) induced the expression of CsCMK and CsHDS by 2.3- and 1.5-fold,respectively.The CsFPS expression was approximately 2-fold higher when treated with DXP,IPP or DMAPP than the untreated control,but this induction was not observed with the acetyl-CoA treatment.Our studies indicated that expression of CsAACT,CsHMGS,CsCMK,CsHDS,and CsFPS were metabolite-mediated in a different extent.展开更多
Fresh leaves of tea cultivar Shuchazao were harvested from five different stages of shoot development including single-bud(SB),one leaf and one bud(BL1),two leaves and one bud(BL2),three leaves and one bud(BL3)and mat...Fresh leaves of tea cultivar Shuchazao were harvested from five different stages of shoot development including single-bud(SB),one leaf and one bud(BL1),two leaves and one bud(BL2),three leaves and one bud(BL3)and mature leaves(ML,including five leaves).The contents of tea-specific components,including caffeine,catechins and amino acids,in tea leaves were extracted and analyzed using the HPLC technique.The results showed that the content of caffeine in the buds in BL3 stage was generally the highest,while it did not change much in SB,BL1 and BL2 stages.The content of caffeine in the leaves at the same leaf-age was similar in five different development stages.The total contents of catechins in the first leaf were higher than that in the buds in all five development stages,and it was the highest in the first leaf at BL1 stage,but it decreased with the increase of the leaf-age.As far as the monomeric catechins were concerned,non-ester type catechins and ester type catechins can be detected in the buds or leaves in the five development stages.The majority of catechins were epigallocatechingallate(EGCG),which showed a similar variation tendency as that of total catechins.However,the contents of non-ester type catechins such as epicatechingallate(EGC),epicatechin(EC) and gallocatechin(GC) were higher in buds than in leaves,which were opposite to the content variation trends of ester type catechins in the course of shoot development.Theanine was the major amino acids in all development stages of tender shoots,and its content in the stage of single-bud was the highest.The content of theanine in buds was three or four times higher than in leaves,and the older the leaf-age was,the less theanine existed in the leaves.展开更多
基金supported by the National Natural Science Foundation of China project (306713312)
文摘The plant-specific NAC(NAM,ATAF1 /2,CUC2) transcription factors play important roles in stess responses and devlopment in plants,but little was known about NACs in tea plants(Camellia sinensis).In this study,a fulllength cDNA sequence(CsNAC) was isolated by suppressive subtractive hybridization(SSH) in Ectropic oblique feeding-induced tea plants.Gene sequence analysis showed that the putative protein of CsNAC contained a conserved NAC domain,which is the typical characteristic of NAC transcription factors.qRT-PCR analysis revealed that CsNAC was suppressed by Ectropis oblique feeding and mechanical damage.Treatment of defence-related homones methyl jasmonate(MeJA) decreased the transcript abudance of CsNAC and salicylic acid(SA) could induce the expression of CsNAC.The transcript levels of CsNAC was down-regulated after applying abscisic acid(ABA) and the expression patterns of CsNAC were different by drought or cold stress.Subcellular localization analysis revealed that CsNAC protein was localized in the nucleus.These results suggested that CsNAC may play a role in defense against insects and adaptation to abiotic stresses.
基金funded by the National Science Foundation in China (#31070614 to S.Wei)Fund for the Doctoral Program of Higher Education of The ministry of Education(#20123418110002,to S.Wei)+1 种基金the Program for Changjiang Scholars and Innovative Research Team in Universities (IRT1101 to Z.Z.Zhang)the "Twelfth Five-Year" National Key Basic Research and Development Project (973) in China (2012CB722903 to Xiao-Chun Wan)
文摘Terpenoids play important roles in productivity and product quality in tea(Camellia sinensis),not only because volatile terpenoids contribute significantly to the aroma of teas,but terpenoid-derived light harvesting pigments and phytohormones such as strigolactones implement photosynthesis and branching in plants.All terpenoids are derived from isopentenyl diphosphate(IPP),dimethylallyl diphosphate(DMAPP) produced by methyl-erythritol-phosphate(MEP) and mevalonate(MVA) pathways,the early steps of isoprenoid biosynthesis.For the purpose to determine key genes in the MEP and MVA pathways in C.sinensis,five genes with complete coding sequence and three with partial sequence were obtained based on previously attained transcriptome data and polymerase chain reaction approach in this study.In silico analyses suggested that the five genes with full coding sequence individually encoded acetyl-CoA C-acetyltransferase(CsAACT),3-hydroxy-3-methylglutaryl-CoA synthase(CsHMGS),4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol kinase(CsCMK),1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate synthase(CsHDS),and farnesyl pyrophosphate synthase(CsFPS).Additionally,studies on metabolite-mediated gene expression were performed using tea cell suspensions and leaf-disc cultures.Our data showed that the addition of acetyl-CoA increased the transcript level of CsAACT and CsHMGS by 1.5- and 3-fold,respectively.The addition of deoxy-D-xylulose 5-phosphate(DXP) induced the expression of CsCMK and CsHDS by 2.3- and 1.5-fold,respectively.The CsFPS expression was approximately 2-fold higher when treated with DXP,IPP or DMAPP than the untreated control,but this induction was not observed with the acetyl-CoA treatment.Our studies indicated that expression of CsAACT,CsHMGS,CsCMK,CsHDS,and CsFPS were metabolite-mediated in a different extent.
基金supported by national 973 plan (973 cb722903)Changjiang scholars and innovative team development plan (IRT1101)+1 种基金national natural science foundation of China (31170283)the specialized research fund for the doctoral program of institutions of higher learning (2011341830001)
文摘Fresh leaves of tea cultivar Shuchazao were harvested from five different stages of shoot development including single-bud(SB),one leaf and one bud(BL1),two leaves and one bud(BL2),three leaves and one bud(BL3)and mature leaves(ML,including five leaves).The contents of tea-specific components,including caffeine,catechins and amino acids,in tea leaves were extracted and analyzed using the HPLC technique.The results showed that the content of caffeine in the buds in BL3 stage was generally the highest,while it did not change much in SB,BL1 and BL2 stages.The content of caffeine in the leaves at the same leaf-age was similar in five different development stages.The total contents of catechins in the first leaf were higher than that in the buds in all five development stages,and it was the highest in the first leaf at BL1 stage,but it decreased with the increase of the leaf-age.As far as the monomeric catechins were concerned,non-ester type catechins and ester type catechins can be detected in the buds or leaves in the five development stages.The majority of catechins were epigallocatechingallate(EGCG),which showed a similar variation tendency as that of total catechins.However,the contents of non-ester type catechins such as epicatechingallate(EGC),epicatechin(EC) and gallocatechin(GC) were higher in buds than in leaves,which were opposite to the content variation trends of ester type catechins in the course of shoot development.Theanine was the major amino acids in all development stages of tender shoots,and its content in the stage of single-bud was the highest.The content of theanine in buds was three or four times higher than in leaves,and the older the leaf-age was,the less theanine existed in the leaves.
