-
Categories
-
Pharmaceutical Intermediates
-
Active Pharmaceutical Ingredients
-
Food Additives
- Industrial Coatings
- Agrochemicals
- Dyes and Pigments
- Surfactant
- Flavors and Fragrances
- Chemical Reagents
- Catalyst and Auxiliary
- Natural Products
- Inorganic Chemistry
-
Organic Chemistry
-
Biochemical Engineering
- Analytical Chemistry
-
Cosmetic Ingredient
- Water Treatment Chemical
-
Pharmaceutical Intermediates
Promotion
ECHEMI Mall
Wholesale
Weekly Price
Exhibition
News
-
Trade Service
Tea tree purine alkaloids mainly include caffeine, theobromine and theophylline
.
Theophylline (1,3,7,9-tetramethyluric acid) is a natural product with significant pharmacological activities such as antidepressant, sedative, hypnotic and so on, while caffeine (1,3,7-trimethylxanthine) is both an important tea quality ingredient and some special groups are very sensitive
to it.
Therefore, breeding tea tree varieties high in theophylline and/or low in caffeine will increase the health benefits of tea and promote consumption
.
However, the synthesis and regulation mechanism of theophylline and theophylline have not been fully elucidated, and the related excellent genes have not been fully explored
.
.
Theophylline (1,3,7,9-tetramethyluric acid) is a natural product with significant pharmacological activities such as antidepressant, sedative, hypnotic and so on, while caffeine (1,3,7-trimethylxanthine) is both an important tea quality ingredient and some special groups are very sensitive
to it.
Therefore, breeding tea tree varieties high in theophylline and/or low in caffeine will increase the health benefits of tea and promote consumption
.
However, the synthesis and regulation mechanism of theophylline and theophylline have not been fully elucidated, and the related excellent genes have not been fully explored
.
Recently, Horticulture Research, the top 1 journal of JCR horticulture, published online the innovation team of our tea germplasm resources entitled "A novel TcS allele conferring the high-theacrine and low-caffeine traits and havin.
" g potential use in tea plant breeding" (paper 1) and "Deeply functional identification of TCS1 alleles provides efficient technical paths for low-caffeine breeding of tea plants" (Thesis 2) Research paper
.
" g potential use in tea plant breeding" (paper 1) and "Deeply functional identification of TCS1 alleles provides efficient technical paths for low-caffeine breeding of tea plants" (Thesis 2) Research paper
.
The researchers first constructed an F1 population of more than 180 individuals by artificial hybridization of non-theophylline 'Zhongcha 302' (ZC302) and the specific resource of theophylline 'Milk Bitter Tea' (RY), and then constructed multiple artificial hybrid populations
with the single plant of Homotheophylline F1 as the father.
The study found that the content of theophylline in F1 individuals was highly negatively correlated with the content of caffeine (R2 >0.
9), and the individuals with high picylline were separated
from those without theophylline by 1:1.
Mixed-group transcriptome sequencing, molecular marker localization and gene expression analysis showed that the theophylline synthetase (TcS) gene was a key candidate gene for determining the traits of homotheophylline, and further clarified the function of TcS by stabilizing the genetic transformation of
tobacco.
Of the 30 tea plant resources with a wide genetic background, only 8 resources contained the TcS gene
.
In vitro enzyme activity assays showed higher protease activity encoded by TcS in 'RY', and further demonstrated that amino acid 241 was a key residue
of TcS using mutation experiments.
Compared with other resources, the TcS promoter of 'RY' had a deletion of 234 bp and an insertion of 271 bp, and the results of GUS histochemical analysis and diluciferase activity assays showed that the TcS promoter activity in 'Milk Bitter Tea' was relatively high
.
A functional marker was developed based on "Insertion of TcS promoter 271 bp", which is co-isolated
from both the F1 population of 'RY' and the homotheophylline individuals in the F2 population.
The above results show that the new TcS allele leads to the formation of high theophylline and low caffeine traits in 'RY' and its offspring
.
with the single plant of Homotheophylline F1 as the father.
The study found that the content of theophylline in F1 individuals was highly negatively correlated with the content of caffeine (R2 >0.
9), and the individuals with high picylline were separated
from those without theophylline by 1:1.
Mixed-group transcriptome sequencing, molecular marker localization and gene expression analysis showed that the theophylline synthetase (TcS) gene was a key candidate gene for determining the traits of homotheophylline, and further clarified the function of TcS by stabilizing the genetic transformation of
tobacco.
Of the 30 tea plant resources with a wide genetic background, only 8 resources contained the TcS gene
.
In vitro enzyme activity assays showed higher protease activity encoded by TcS in 'RY', and further demonstrated that amino acid 241 was a key residue
of TcS using mutation experiments.
Compared with other resources, the TcS promoter of 'RY' had a deletion of 234 bp and an insertion of 271 bp, and the results of GUS histochemical analysis and diluciferase activity assays showed that the TcS promoter activity in 'Milk Bitter Tea' was relatively high
.
A functional marker was developed based on "Insertion of TcS promoter 271 bp", which is co-isolated
from both the F1 population of 'RY' and the homotheophylline individuals in the F2 population.
The above results show that the new TcS allele leads to the formation of high theophylline and low caffeine traits in 'RY' and its offspring
.
Theophylphilic synthase (TCS1) is the most critical N-methyltransferase (NMT) in the caffeine biosynthetic pathway, which catalyzes the methylation
of N-3 and N-1.
There is an independent evolutionary mechanism of NMTs involved in the biosynthesis of caffeine and theobromine and other purine alkaloids, which makes TCS1 have a variety of sequence variations
.
In addition to the 8 TCS1 allele variants previously discovered, Paper 2 identified a novel allele TCS1h
in 673 tea plant germplasm resources.
The results of in vitro activity analysis showed that TCS1h had both theobromine synthase (TS) and caffeine synthase (CS) activities, and it was clear through point mutation experiments that in addition to the 225th amino acid residue, the 269th amino acid residue also determined the activity of CS
.
The study found that the content of caffeine and theophylline was related to the expression of corresponding functional genes and alleles, and the presence and level of gene expression largely determined the content
of purine alkaloids in tea plants.
GUS histochemical analysis and diluciferase detection showed that the promoter activity of TCS1e and TCS1f was significantly low, and a key cis-acting element (G-box)
was further identified by deletion mutation and point mutation experiments.
Based on the results of this study and previous results, the nine TCS1 alleles that have been discovered are divided into three functional types (only TS activity, TS and CS activity but low transcription level, TS and CS activity and high transcription level), and a technical path
of low caffeine breeding is proposed on the basis of years of germplasm innovation practice.
of N-3 and N-1.
There is an independent evolutionary mechanism of NMTs involved in the biosynthesis of caffeine and theobromine and other purine alkaloids, which makes TCS1 have a variety of sequence variations
.
In addition to the 8 TCS1 allele variants previously discovered, Paper 2 identified a novel allele TCS1h
in 673 tea plant germplasm resources.
The results of in vitro activity analysis showed that TCS1h had both theobromine synthase (TS) and caffeine synthase (CS) activities, and it was clear through point mutation experiments that in addition to the 225th amino acid residue, the 269th amino acid residue also determined the activity of CS
.
The study found that the content of caffeine and theophylline was related to the expression of corresponding functional genes and alleles, and the presence and level of gene expression largely determined the content
of purine alkaloids in tea plants.
GUS histochemical analysis and diluciferase detection showed that the promoter activity of TCS1e and TCS1f was significantly low, and a key cis-acting element (G-box)
was further identified by deletion mutation and point mutation experiments.
Based on the results of this study and previous results, the nine TCS1 alleles that have been discovered are divided into three functional types (only TS activity, TS and CS activity but low transcription level, TS and CS activity and high transcription level), and a technical path
of low caffeine breeding is proposed on the basis of years of germplasm innovation practice.
The above results will help to understand the genetic basis of the formation of low coffee traits and high theophylline traits, and the functional markers developed will accelerate the speed of variety cultivation, and provide theoretical and technical support and excellent genetic resources
for the selection and breeding of high theophylline and/or low theophylline tea varieties.
for the selection and breeding of high theophylline and/or low theophylline tea varieties.
Associate Researcher Jin Jiqiang and Professor Yao Mingzhe of the tea germplasm resources innovation team of our institute are the co-corresponding authors of Paper 1, and Zhong Hong, a graduated master's student, and Wang Yi and Xuan Furong, master's students, are co-first authors
.
Associate Professor Jin Jiqiang and Professor Chen Liang are the co-corresponding authors of Paper 2, and Master student Wang Yi and graduated Master Student Liu Yufei are co-first authors
.
The relevant research was completed
under the support of the National Natural Science Foundation of China, the Natural Science Foundation of Zhejiang Province, the Major Science and Technology Project for the Selection and Breeding of New Agricultural Varieties of Zhejiang Province, the Ministry of Finance and the Ministry of Agriculture and Rural Affairs: Special Fund for the Construction of Modern Agricultural Industrial Technology System, and the Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences.
.
Associate Professor Jin Jiqiang and Professor Chen Liang are the co-corresponding authors of Paper 2, and Master student Wang Yi and graduated Master Student Liu Yufei are co-first authors
.
The relevant research was completed
under the support of the National Natural Science Foundation of China, the Natural Science Foundation of Zhejiang Province, the Major Science and Technology Project for the Selection and Breeding of New Agricultural Varieties of Zhejiang Province, the Ministry of Finance and the Ministry of Agriculture and Rural Affairs: Special Fund for the Construction of Modern Agricultural Industrial Technology System, and the Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences.
