In plant immunity,the mutually antagonistic hormones salicylic acid(SA)and jasmonic acid(JA)are implicated in resistance to biotrophic and necrotrophic pathogens,respectively.Promoters that can respond to both SA and ...In plant immunity,the mutually antagonistic hormones salicylic acid(SA)and jasmonic acid(JA)are implicated in resistance to biotrophic and necrotrophic pathogens,respectively.Promoters that can respond to both SA and JA signals are urgently needed to engineer plants with enhanced resistance to a broad spectrum of pathogens.However,few natural pathogen-inducible promoters are available for this purpose.To address this problem,we have developed a strategy to synthesize dual SA-and JA-responsive promoters by combining SA-and JA-responsive cis elements based on the interaction between their cognate transacting factors.The resulting promoters respond rapidly and strongly to both SA and Methyl Jasmonate(MeJA),as well as different types of phytopathogens.When such a synthetic promoter was used to control expression of an antimicrobial peptide,transgenic plants displayed enhanced resistance to a diverse range of biotrophic,necrotrophic,and hemi-biotrophic pathogens.A dual-inducible promoter responsive to the antagonistic signals auxin and cytokinin was generated in a similar manner,confirming that our strategy can be used for the design of other biotically or abiotically inducible systems.展开更多
The engineering application of natural hyperaccumulators In removing or inactivating metal pollutants from soil and surface water In field trials mostly presents the insurmountable shortcoming of low efficiency owing ...The engineering application of natural hyperaccumulators In removing or inactivating metal pollutants from soil and surface water In field trials mostly presents the insurmountable shortcoming of low efficiency owing to their little biomass and slow growth. Based on further understanding of the molecular mechanism of metal uptake, translocation, and also the separation, identification, and cloning of some related functional genes, this article highlights and summarizes In detail the advances in research on transgenlc techniques, such as Agrobacterlurn tumefaciens-medlated transformation and particle bombardment, in breeding of plants for metal resistance and accumulation, and points out that deepening the development of transgenlc plants Is one of the efficient approaches to improving phytoremedlatlon efficiency of metalcontaminated environments. From the viewpoint of sustainable development, governments should strengthen support to the development of genetic engineering for metal resistance and accumulation In plants.展开更多
After pre-culture and treatment of osmosis, cotyledons of immature peanut (Arachis hypogaea L.) zygotic embryos were transformed via particle bombardment with a plasmid containing a chimeric hph gene conferring resist...After pre-culture and treatment of osmosis, cotyledons of immature peanut (Arachis hypogaea L.) zygotic embryos were transformed via particle bombardment with a plasmid containing a chimeric hph gene conferring resistance to hygromycin and a chimeric intron-gus gene. Selection for hygromycin resistant calluses and somatic embryos was initiated at 10th d post-bombardment on medium containing 10-25 mg/L hygromycin. Under continuous selection, hygromycin resistant plantlets were regenerated from somatic embryos and were recovered from nearly 1.6% of the bombarded cotyledons. The presence and integration of foreign DNA in regenerated hygromycin resistant plants was confirmed by PCR (polymerase chain reaction) for the intron-gus gene and by Southern hybridization of the hph gene. GUS enzyme activity was detected in leaflets from transgenic plants but not from control, non-transformed plants. The production of transgenic plants are mainly based on a newly improved somatic embryogenesis regeneration system developed by us.展开更多
Cryptogein (Crypt), an elicitin secreted from Phytophthora cryptogea, was used for genetic engineering of biotic and abiotic resistance plants. We generated trans-genic tobacco plants harboring a rice phenylalanine am...Cryptogein (Crypt), an elicitin secreted from Phytophthora cryptogea, was used for genetic engineering of biotic and abiotic resistance plants. We generated trans-genic tobacco plants harboring a rice phenylalanine ammo-nia-lyase (PAL) promoter and Crypt fusion gene (PAL::Crypt) or the mutated Crypt (mutation of the lysine at the position 13 to valine) under the control CaMV35S promoter (CaMV35S::CryK13V). T2 progeny of the transgenic plants showed significantly enhanced disease resistance to patho-gens of fungal Phytophthora parasitica var nicotiana (Ppn) and Alternaria alternata, and bacterial Pseudomonas syringae pv tabaci. The amount of mRNA accumulation of Crypt and CryK13V was quite low in the transgenic lines analyzed by Northern blot, and was detected by a reverse transcription PCR method. Plants harboring PAL::Crypt construct showed faster and stronger induction of PR-1a gene after Ppn inoculation than that in the wild-type plants. The re-sults suggested that the inducible PAL promoter could rap-idly respond to pathogen attack and efficiently suppress the pathogen infection. Furthermore, the enhanced tolerance to salt stress in both of the Crypt and CryK13V expressing tobacco plants was also observed compared with that in the control plants. The constitutive expression of PR and tran-scription factor genes in the transformants was probably associated with the salt tolerance. The above observations suggested that a cross-talk between biotic and abiotic stresses existed in tobacco plants.展开更多
Plant diseases caused by diverse pathogens lead to a serious reduction in crop yield and threaten food security worldwide.Genetic improvement of plant immunity is considered as the most effective and sustainable appro...Plant diseases caused by diverse pathogens lead to a serious reduction in crop yield and threaten food security worldwide.Genetic improvement of plant immunity is considered as the most effective and sustainable approach to control crop diseases.In the last decade,our understanding of plant immunity at both molecular and genomic levels has improved greatly.Combined with advances in biotechnologies,particularly clustered regularly interspaced short palindromic repeat(CRISPR)/Cas9-based genome editing,we can now rapidly identify new resistance genes and engineer disease-resistance crop plants like never before.In this review,we summarize the current knowledge of plant immunity and outline existing and new strategies for disease resistance improvement in crop plants.We also discuss existing challenges in this field and suggest directions for future studies.展开更多
基金supported by the National Natural Science Foundation of China(31071463)Chongqing Foundation for leaders of disciplines in science(cstc2014kjcxljrc005)the Chongqing Research Program of Basic Research and Frontier Technology(cstc2017jcyjB0316).
文摘In plant immunity,the mutually antagonistic hormones salicylic acid(SA)and jasmonic acid(JA)are implicated in resistance to biotrophic and necrotrophic pathogens,respectively.Promoters that can respond to both SA and JA signals are urgently needed to engineer plants with enhanced resistance to a broad spectrum of pathogens.However,few natural pathogen-inducible promoters are available for this purpose.To address this problem,we have developed a strategy to synthesize dual SA-and JA-responsive promoters by combining SA-and JA-responsive cis elements based on the interaction between their cognate transacting factors.The resulting promoters respond rapidly and strongly to both SA and Methyl Jasmonate(MeJA),as well as different types of phytopathogens.When such a synthetic promoter was used to control expression of an antimicrobial peptide,transgenic plants displayed enhanced resistance to a diverse range of biotrophic,necrotrophic,and hemi-biotrophic pathogens.A dual-inducible promoter responsive to the antagonistic signals auxin and cytokinin was generated in a similar manner,confirming that our strategy can be used for the design of other biotically or abiotically inducible systems.
基金Supported by the National Natural Science Foundation of China （30471418）.
文摘The engineering application of natural hyperaccumulators In removing or inactivating metal pollutants from soil and surface water In field trials mostly presents the insurmountable shortcoming of low efficiency owing to their little biomass and slow growth. Based on further understanding of the molecular mechanism of metal uptake, translocation, and also the separation, identification, and cloning of some related functional genes, this article highlights and summarizes In detail the advances in research on transgenlc techniques, such as Agrobacterlurn tumefaciens-medlated transformation and particle bombardment, in breeding of plants for metal resistance and accumulation, and points out that deepening the development of transgenlc plants Is one of the efficient approaches to improving phytoremedlatlon efficiency of metalcontaminated environments. From the viewpoint of sustainable development, governments should strengthen support to the development of genetic engineering for metal resistance and accumulation In plants.
基金the Natinnal Biotechnology Reseaxch Project of 863 High Technology, contract No. 101-01-01-02.
文摘After pre-culture and treatment of osmosis, cotyledons of immature peanut (Arachis hypogaea L.) zygotic embryos were transformed via particle bombardment with a plasmid containing a chimeric hph gene conferring resistance to hygromycin and a chimeric intron-gus gene. Selection for hygromycin resistant calluses and somatic embryos was initiated at 10th d post-bombardment on medium containing 10-25 mg/L hygromycin. Under continuous selection, hygromycin resistant plantlets were regenerated from somatic embryos and were recovered from nearly 1.6% of the bombarded cotyledons. The presence and integration of foreign DNA in regenerated hygromycin resistant plants was confirmed by PCR (polymerase chain reaction) for the intron-gus gene and by Southern hybridization of the hph gene. GUS enzyme activity was detected in leaflets from transgenic plants but not from control, non-transformed plants. The production of transgenic plants are mainly based on a newly improved somatic embryogenesis regeneration system developed by us.
文摘Cryptogein (Crypt), an elicitin secreted from Phytophthora cryptogea, was used for genetic engineering of biotic and abiotic resistance plants. We generated trans-genic tobacco plants harboring a rice phenylalanine ammo-nia-lyase (PAL) promoter and Crypt fusion gene (PAL::Crypt) or the mutated Crypt (mutation of the lysine at the position 13 to valine) under the control CaMV35S promoter (CaMV35S::CryK13V). T2 progeny of the transgenic plants showed significantly enhanced disease resistance to patho-gens of fungal Phytophthora parasitica var nicotiana (Ppn) and Alternaria alternata, and bacterial Pseudomonas syringae pv tabaci. The amount of mRNA accumulation of Crypt and CryK13V was quite low in the transgenic lines analyzed by Northern blot, and was detected by a reverse transcription PCR method. Plants harboring PAL::Crypt construct showed faster and stronger induction of PR-1a gene after Ppn inoculation than that in the wild-type plants. The re-sults suggested that the inducible PAL promoter could rap-idly respond to pathogen attack and efficiently suppress the pathogen infection. Furthermore, the enhanced tolerance to salt stress in both of the Crypt and CryK13V expressing tobacco plants was also observed compared with that in the control plants. The constitutive expression of PR and tran-scription factor genes in the transformants was probably associated with the salt tolerance. The above observations suggested that a cross-talk between biotic and abiotic stresses existed in tobacco plants.
基金supported by grants from National Key R&D Program of China (2021YFA1300701) (to J.-M.Z.)the National Natural Science Foundation of China (31825022 and 32121003) (to X.W.C.)+2 种基金the Hainan Excellent Talent Team (to J.-M.Z.)the State Key Laboratory of Plant Genomics (SKLPG2016B-2) (to J.-M.Z.)the National Natural Science Foundation of China (32072407) (to X.B.Z.)
文摘Plant diseases caused by diverse pathogens lead to a serious reduction in crop yield and threaten food security worldwide.Genetic improvement of plant immunity is considered as the most effective and sustainable approach to control crop diseases.In the last decade,our understanding of plant immunity at both molecular and genomic levels has improved greatly.Combined with advances in biotechnologies,particularly clustered regularly interspaced short palindromic repeat(CRISPR)/Cas9-based genome editing,we can now rapidly identify new resistance genes and engineer disease-resistance crop plants like never before.In this review,we summarize the current knowledge of plant immunity and outline existing and new strategies for disease resistance improvement in crop plants.We also discuss existing challenges in this field and suggest directions for future studies.
