Non-heading Chinese cabbage, a variety of Brassica campestris, is an important vegetable crop in the Yangtze River Basin of China. However,the immaturity of its stable transformation system and its low transformation ...Non-heading Chinese cabbage, a variety of Brassica campestris, is an important vegetable crop in the Yangtze River Basin of China. However,the immaturity of its stable transformation system and its low transformation efficiency limit gene function research on non-heading Chinese cabbage. Agrobacterium rhizogenes-mediated(ARM) transgenic technology is a rapid and effective transformation method that has not yet been established for non-heading Chinese cabbage plants. Here, we optimized conventional ARM approaches(one-step and two-step transformation methods) suitable for living non-heading Chinese cabbage plants in nonsterile environments. Transgenic roots in composite non-heading Chinese cabbage plants were identified using phenotypic detection, fluorescence observation, and PCR analysis. The transformation efficiency of a two-step method on four five-day-old non-heading Chinese cabbage seedlings(Suzhouqing, Huangmeigui, Wuyueman, and Sijiu Caixin) was 43.33%-51.09%, whereas using the stout hypocotyl resulted in a transformation efficiency of 54.88% for the 30-day-old Sijiu Caixin.The one-step method outperformed the two-step method;the transformation efficiency of different varieties was above 60%, and both methods can be used to obtain transgenic roots for functional studies within one month. Finally, optimized ARM transformation methods can easily,quickly, and effectively produce composite non-heading Chinese cabbage plants with transgenic roots, providing a reliable foundation for gene function research and non-heading Chinese cabbage genetic improvement breeding.展开更多
Expression of rol genes from Ri plasmid of Agrobacterium rhizogenes not only leads to the excessive formation of adventitious roots, but also exhibits various genetically modified characteristics that have bro...Expression of rol genes from Ri plasmid of Agrobacterium rhizogenes not only leads to the excessive formation of adventitious roots, but also exhibits various genetically modified characteristics that have broad prospects for the application of plant genetic improvement. Since the 1980s of the last century, much progress has been made in the studies of A. rhizogenes, in particular the agropine type Ri plasmid rol genes and their applications for plant genetic improvement, which involves the structure and function of Ri plasmid, the characters of rol genes, the influence of rol genes expression on plants growth and development, and the applications of rol genes for genetic improvement of forest tree. In this paper, the advances in this field are reviewed and the existing problems about the application of rol genes for genetic improvement of forest tree are also discussed.展开更多
Soybean is one of the world's most important oil and protein crops. Efficient transformation is a key factor for the improvement of soybean by genetic modification. We describe an optimized protocol for the Agroba...Soybean is one of the world's most important oil and protein crops. Efficient transformation is a key factor for the improvement of soybean by genetic modification. We describe an optimized protocol for the Agrobacterium rhizogenes-mediated transformation of soybean and the induction of hairy root development in vitro. Cotyledons with 0.5-cm hypocotyls were cut from 5-day-old seedlings and used as explants. After infection and co-cultivation,hairy roots were produced in induction culture medium after 10–12 days. Using this method, 90%–99% of the infected explants of five different cultivars produced hairy roots within one month. Observations using reporter constructs showed that 30%–60% of the hairy roots induced were transformed. Based on high transformation efficiency and short transformation period, this method represents an efficient and rapid platform for study of soybean gene function.展开更多
The legume forage Alhagi pseudoalhagi was transformed by the Agrobacterium rhizogenes strain A4 using cotyledon and hypocotyl segments as infection materials. Regenerated plants were achieved from sterile calli derive...The legume forage Alhagi pseudoalhagi was transformed by the Agrobacterium rhizogenes strain A4 using cotyledon and hypocotyl segments as infection materials. Regenerated plants were achieved from sterile calli derived from hairy roots, which occurred at or near the infection sites. The regenerated plants from hairy root were characterized by normal leaf morphology and stem growth but a shallow and more extensive root system than normal plants. Opine synthesis, PCR and Southern blot confirmed that T- DNA had been integrated into the A. pseudoalhagi genome. Acetosyringone (AS) was found to be vital for successful transformation of A. pseudoalhagi.展开更多
By screening a native plant extract library we identified Solidago nemoralis as a novel source of agonists for alpha7 nicotinic receptors for acetylcholine with therapeutic potential. The next phase of our drug discov...By screening a native plant extract library we identified Solidago nemoralis as a novel source of agonists for alpha7 nicotinic receptors for acetylcholine with therapeutic potential. The next phase of our drug discovery strategy is to increase the yields of active compounds in the plant species by gain of function mutations in hairy root cultures [1]. Here we report a protocol for Agrobacterium rhizogenes-mediated genetic transformation of hairy root cultures of Solidago nemoralis which will enable this. Leaf explants of this species were successfully transformed with a frequency of 30%-35% using A. rhizogenes strain R1000 harboring the binary vector pCambia 1301. Transformation was confirmed using the β-glucuronidase (GUS) histochemical assay. Transformed hairy roots showed spontaneous regeneration of adventitious shoots in media without the addition of cytokines, albeit at very low frequency. However, media supplementation with auxin (α-naphthaleneacetic acid, NAA) increased shoot regeneration frequency to 35% and resulted in viable adventitious shoots. Transformation was confirmed at all phases of plant regeneration by GUS staining. Hairy root transformation of Solidago altissima has been previously reported, but this is the first report of genetic transformation of S. nemoralis. The protocol will allow for a large population of activation tagged mutants of S. nemoralis to be generated which will be then screened for the presence of stable mutants which are over-producing metabolites with activity at alpha7 nicotinic receptors. These over-producing mutant cultures will then be regenerated into intact mutant plants.展开更多
A rapid, efficient and high-performance transformation protocol employing Agrobacterium rhizogenes was developed for the common bean Phaseolus vulgaris. In this study, we examined competencies of various protocols to ...A rapid, efficient and high-performance transformation protocol employing Agrobacterium rhizogenes was developed for the common bean Phaseolus vulgaris. In this study, we examined competencies of various protocols to induce and explants that respond to hairy root transformation in bean plants. Utilizing young seedlings with severed radicles/hypocotyls, we developed a highly efficient procedure for achieving hairy root transformation frequencies as high as 100% as visualized by GUS reporter gene expression system. Transgenic hairy roots in these young composite plants were susceptible to nodulation by rhizobia, and form an excellent system for high throughput genomic analysis to study root biology and endosymbiosis in common bean.展开更多
Virus-induced gene silencing(VIGS)and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)systems are effective technologies for rapid and accurate gene function verification...Virus-induced gene silencing(VIGS)and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)systems are effective technologies for rapid and accurate gene function verification in modern plant biotechnology.However,the investigation of gene silencing and editing in radish remains limited.In this study,a bleaching phenotype was generated through the knockdown of RsPDS using tobacco rattle virus(TRV)-and turnip yellow mosaic virus(TYMV)-mediated gene silencing vectors.The TYMV-mediated gene silencing efficiency was higher than the TRV-based VIGS system in radish.The expression level of RsPDS was significantly inhibited using VIGS in'NAU-067'radish leaves.The rootless seedlings of‘NAU-067'were infected with Agrobacterium rhizogenes using the 2300GN-Ubi-RsPDS-Cas9 vector with two target sequences.Nine adventitious roots were blue with GUs staining,and four of these adventitious roots were edited at target sequence 1 of the RsPDS gene as indicated by Sanger sequencing.Furthermore,albino lines were generated with A.tumefaciens-mediated transformation of radish cotyledons.Five base substitutions and three base deletions occurred at target sequence 2 in Line 1,and three base insertions and three base substitutions occurred at target sequence 1 in Line 2.This study shows that VIGS and CRISPR/Cas9 techniques can be employed to precisely verify the biological functions of genes in radish,which will facilitate the genetic improvement of vital horticultural traits in radish breeding programs.展开更多
Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars bas...Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars based on mapping and cloning of resistant genes is commonly regarded as the most cost-effective and efficient way to fight against this disease.The traditional way of R gene functional validation requires stable transformation that is both time-and labor-consuming.In this study,a rapid and efficient hairy-root transgenic protocol mediated by Agrobacterium rhizogenes was developed.The transformation positive rate was over 80%in Brassica napus showed by GUS reporter gene and this transformation only took 1/6 of the time compared with stable transformation.The system was applicable to different B.napus varieties and other cruciferous crops including Brassica rapa and Brassica oleracea.In particular,two known CR genes,CRA3.7.1 and CRA8.2.4 were used respectively,as example to show that the system works well for CR gene study combined with subsequent P.brassicae infection in B.napus.Most importantly,it works both in over-expression that led to disease resistance,as well as in RNAi which led to disease susceptible phenotype.Therefore,this system can be used in batch-wise identification of CR genes,and also offered the possibility of manipulating key genes within the P.brassicae genome that could improve our knowledge on host-pathogen interaction.展开更多
基金funded by National Natural Science Foundation of China (Grant No.32072575)Postgraduate Research & Practice Innovation Program of Jiangsu Province (Grant No.KYCX20_0588)National Vegetable Industry Technology System (Grant No.CARS-23-A16)。
文摘Non-heading Chinese cabbage, a variety of Brassica campestris, is an important vegetable crop in the Yangtze River Basin of China. However,the immaturity of its stable transformation system and its low transformation efficiency limit gene function research on non-heading Chinese cabbage. Agrobacterium rhizogenes-mediated(ARM) transgenic technology is a rapid and effective transformation method that has not yet been established for non-heading Chinese cabbage plants. Here, we optimized conventional ARM approaches(one-step and two-step transformation methods) suitable for living non-heading Chinese cabbage plants in nonsterile environments. Transgenic roots in composite non-heading Chinese cabbage plants were identified using phenotypic detection, fluorescence observation, and PCR analysis. The transformation efficiency of a two-step method on four five-day-old non-heading Chinese cabbage seedlings(Suzhouqing, Huangmeigui, Wuyueman, and Sijiu Caixin) was 43.33%-51.09%, whereas using the stout hypocotyl resulted in a transformation efficiency of 54.88% for the 30-day-old Sijiu Caixin.The one-step method outperformed the two-step method;the transformation efficiency of different varieties was above 60%, and both methods can be used to obtain transgenic roots for functional studies within one month. Finally, optimized ARM transformation methods can easily,quickly, and effectively produce composite non-heading Chinese cabbage plants with transgenic roots, providing a reliable foundation for gene function research and non-heading Chinese cabbage genetic improvement breeding.
文摘Expression of rol genes from Ri plasmid of Agrobacterium rhizogenes not only leads to the excessive formation of adventitious roots, but also exhibits various genetically modified characteristics that have broad prospects for the application of plant genetic improvement. Since the 1980s of the last century, much progress has been made in the studies of A. rhizogenes, in particular the agropine type Ri plasmid rol genes and their applications for plant genetic improvement, which involves the structure and function of Ri plasmid, the characters of rol genes, the influence of rol genes expression on plants growth and development, and the applications of rol genes for genetic improvement of forest tree. In this paper, the advances in this field are reviewed and the existing problems about the application of rol genes for genetic improvement of forest tree are also discussed.
基金supported by the Major Science and Technology Projects of China (2016ZX08010-004)the Ministry of Science and Technology of China (2016YFD0100504)the CAAS (Chinese Academy of Agriculture Sciences) Innovation Project
文摘Soybean is one of the world's most important oil and protein crops. Efficient transformation is a key factor for the improvement of soybean by genetic modification. We describe an optimized protocol for the Agrobacterium rhizogenes-mediated transformation of soybean and the induction of hairy root development in vitro. Cotyledons with 0.5-cm hypocotyls were cut from 5-day-old seedlings and used as explants. After infection and co-cultivation,hairy roots were produced in induction culture medium after 10–12 days. Using this method, 90%–99% of the infected explants of five different cultivars produced hairy roots within one month. Observations using reporter constructs showed that 30%–60% of the hairy roots induced were transformed. Based on high transformation efficiency and short transformation period, this method represents an efficient and rapid platform for study of soybean gene function.
文摘The legume forage Alhagi pseudoalhagi was transformed by the Agrobacterium rhizogenes strain A4 using cotyledon and hypocotyl segments as infection materials. Regenerated plants were achieved from sterile calli derived from hairy roots, which occurred at or near the infection sites. The regenerated plants from hairy root were characterized by normal leaf morphology and stem growth but a shallow and more extensive root system than normal plants. Opine synthesis, PCR and Southern blot confirmed that T- DNA had been integrated into the A. pseudoalhagi genome. Acetosyringone (AS) was found to be vital for successful transformation of A. pseudoalhagi.
文摘By screening a native plant extract library we identified Solidago nemoralis as a novel source of agonists for alpha7 nicotinic receptors for acetylcholine with therapeutic potential. The next phase of our drug discovery strategy is to increase the yields of active compounds in the plant species by gain of function mutations in hairy root cultures [1]. Here we report a protocol for Agrobacterium rhizogenes-mediated genetic transformation of hairy root cultures of Solidago nemoralis which will enable this. Leaf explants of this species were successfully transformed with a frequency of 30%-35% using A. rhizogenes strain R1000 harboring the binary vector pCambia 1301. Transformation was confirmed using the β-glucuronidase (GUS) histochemical assay. Transformed hairy roots showed spontaneous regeneration of adventitious shoots in media without the addition of cytokines, albeit at very low frequency. However, media supplementation with auxin (α-naphthaleneacetic acid, NAA) increased shoot regeneration frequency to 35% and resulted in viable adventitious shoots. Transformation was confirmed at all phases of plant regeneration by GUS staining. Hairy root transformation of Solidago altissima has been previously reported, but this is the first report of genetic transformation of S. nemoralis. The protocol will allow for a large population of activation tagged mutants of S. nemoralis to be generated which will be then screened for the presence of stable mutants which are over-producing metabolites with activity at alpha7 nicotinic receptors. These over-producing mutant cultures will then be regenerated into intact mutant plants.
基金Centro de Ciencias de Genomicas,Universidad Autonoma de Mexico,Cuernavaca,Morelos,Mexico for financial and lab support
文摘A rapid, efficient and high-performance transformation protocol employing Agrobacterium rhizogenes was developed for the common bean Phaseolus vulgaris. In this study, we examined competencies of various protocols to induce and explants that respond to hairy root transformation in bean plants. Utilizing young seedlings with severed radicles/hypocotyls, we developed a highly efficient procedure for achieving hairy root transformation frequencies as high as 100% as visualized by GUS reporter gene expression system. Transgenic hairy roots in these young composite plants were susceptible to nodulation by rhizobia, and form an excellent system for high throughput genomic analysis to study root biology and endosymbiosis in common bean.
基金This work was supported by Jiangsu Seed Industry Revitalization Project,China[JBGS(2021)071]Fundamental Research Funds for the Central Universities,China(YDZX2023019)+3 种基金the National Natural Science Foundation of China(32172579)the earmarked fund for Jiangsu Agricultural Industry Technology System,China[JATS(2023)421]the Jiangsu Postgraduate Scientific Research Innovation Plan,China(KYCX21_0610-2021)the Project Founded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China(PAPD).
文摘Virus-induced gene silencing(VIGS)and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)systems are effective technologies for rapid and accurate gene function verification in modern plant biotechnology.However,the investigation of gene silencing and editing in radish remains limited.In this study,a bleaching phenotype was generated through the knockdown of RsPDS using tobacco rattle virus(TRV)-and turnip yellow mosaic virus(TYMV)-mediated gene silencing vectors.The TYMV-mediated gene silencing efficiency was higher than the TRV-based VIGS system in radish.The expression level of RsPDS was significantly inhibited using VIGS in'NAU-067'radish leaves.The rootless seedlings of‘NAU-067'were infected with Agrobacterium rhizogenes using the 2300GN-Ubi-RsPDS-Cas9 vector with two target sequences.Nine adventitious roots were blue with GUs staining,and four of these adventitious roots were edited at target sequence 1 of the RsPDS gene as indicated by Sanger sequencing.Furthermore,albino lines were generated with A.tumefaciens-mediated transformation of radish cotyledons.Five base substitutions and three base deletions occurred at target sequence 2 in Line 1,and three base insertions and three base substitutions occurred at target sequence 1 in Line 2.This study shows that VIGS and CRISPR/Cas9 techniques can be employed to precisely verify the biological functions of genes in radish,which will facilitate the genetic improvement of vital horticultural traits in radish breeding programs.
基金supported by grants from the Wuhan Science and Technology Major Project on Key techniques of biological breeding and Breeding of new varieties(Grant No.2022021302024851)the special project for sustainable development agenda of innovation demonstration zone(Grant No.202204AC100001-A04)the National Key R&D Program of China(Grant No.2022YFD1200400)。
文摘Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars based on mapping and cloning of resistant genes is commonly regarded as the most cost-effective and efficient way to fight against this disease.The traditional way of R gene functional validation requires stable transformation that is both time-and labor-consuming.In this study,a rapid and efficient hairy-root transgenic protocol mediated by Agrobacterium rhizogenes was developed.The transformation positive rate was over 80%in Brassica napus showed by GUS reporter gene and this transformation only took 1/6 of the time compared with stable transformation.The system was applicable to different B.napus varieties and other cruciferous crops including Brassica rapa and Brassica oleracea.In particular,two known CR genes,CRA3.7.1 and CRA8.2.4 were used respectively,as example to show that the system works well for CR gene study combined with subsequent P.brassicae infection in B.napus.Most importantly,it works both in over-expression that led to disease resistance,as well as in RNAi which led to disease susceptible phenotype.Therefore,this system can be used in batch-wise identification of CR genes,and also offered the possibility of manipulating key genes within the P.brassicae genome that could improve our knowledge on host-pathogen interaction.
