Harpins are bacterial proteins that can enhance plant growth and defense against pathogens and insects. To elaborate whether harpins perform the diverse functions in coordination with the activation of specific promot...Harpins are bacterial proteins that can enhance plant growth and defense against pathogens and insects. To elaborate whether harpins perform the diverse functions in coordination with the activation of specific promoters that contain particular elements, we cloned pathogen-inducible plant promoters PPP1, PPP2, and PPP3 from tobacco and investigated their responses to harpinxoo or its truncated fragments DEG, DIR, and DPR (domains for enhancing plant growth, insect resistance and pathogen resistance). PPP1 contains an internal repeat composed of two tandem 111bp fragments; 111bp in the repeat was deleted in PPP2. PPP3 contains a bacteria-inducible element; PPP1 and PPP2 additionally contain TAC-1 and Eli boxes inducible correspondingly by salicylic acid (SA) and elicitors. Function of cloned PPPs was confirmed based on their activation in transgenic Arabidopsis plants by Ralstonia solanacearum (Ralston) or SA. Harpinxoo, DEG, DIR, or DPR activated PPP1 and PPP2 but not PPP3, consistent with the presence of Eli boxes in promoters. PPP1 was ca. 3-fold more active than PPP2, suggesting that the internal repeat affects levels of the promoter activation.展开更多
To engineer crop disease resistance by utilizing natural defense mechanism that was expressed in the incompatible host-pathogen interactions is expected to result in a durable and broad-spectrum resistance. In order t...To engineer crop disease resistance by utilizing natural defense mechanism that was expressed in the incompatible host-pathogen interactions is expected to result in a durable and broad-spectrum resistance. In order to prove this viewpoint, we amplified the coding region of the glucose oxidase (GO) gene from Aspergillus nigervia PCR and fused it to the pathogen-inducible promoter, Prp1-1. The chimeric gene was cloned into a plant expression vector and conjugated into Agrobacterium. Twenty-three transgenic potato plants were obtained by Agrobacterium-mediated transformation. The integration of GO gene was confirmed by Southern hybridization and the GO gene expression was identified with Kl-starch color reaction. Phytophthora infestans inoculation revealed that the expression of the chimeric transgene was induced by pathogen infection. Most of the transgenic plants exhibited various degrees of enhanced disease resistance. Four of them had lesion sizes reduced to less than half of the non-transgenic展开更多
Botrytis cinerea is a major necrotrophic pathogen responsible for significant crop losses worldwide.Alternative strategies to control B.cinerea are urgently needed to reduce dependence on chemical fungicides,which are...Botrytis cinerea is a major necrotrophic pathogen responsible for significant crop losses worldwide.Alternative strategies to control B.cinerea are urgently needed to reduce dependence on chemical fungicides,which are increasingly ineffective due to resistance and pose environmental risks.In this study,we identified two immunogenic epitopes derived from the B.cinerea cell death-inducing protein BcCrh1 and used them to engineer disease-resistant plants through a novel,spatially compartmentalized dual-epitope immune activation strategy.The first epitope is derived from a 35-amino acid intracellular peptide that exhibits both immunogenicity and cell death-inducing activity,which was mutated to separate these two properties.The second peptide represents an immunogenic portion of the protein that activates extracellular plant immunity.Transcriptomic and metabolomic analyses revealed that these epitopes trigger complementary defense pathways,and their co-expression integrates these responses into a robust,multilayered immunity,providing significantly enhanced protection compared with individual expression.Although constitutive expression of two epitopes conferred resistance,it also led to growth penalties.In contrast,pathogen-inducible expression of two epitopes preserved normal plant development while maintaining strong resistance to both B.cinerea and Pseudomonas syringae in Arabidopsis and tomato.This inducible strategy offers a major advantage by minimizing fitness costs while maximizing protection,highlighting the potential of spatially and temporally targeted epitope-based immune activation for durable and sustainable crop protection.展开更多
The promoter fragments of wheat GstA1 and potato Gst1 have been amplified by PCR, cloned and fused respectively to the minimal promoter sequence of rice actin gene (Act1)) and its 5’ untranslated leader sequence toge...The promoter fragments of wheat GstA1 and potato Gst1 have been amplified by PCR, cloned and fused respectively to the minimal promoter sequence of rice actin gene (Act1)) and its 5’ untranslated leader sequence together with GUS. The constructs with 2 chimeric promoters (WGA and PGA) have been transferred into rice in order to analyze their inducibility patterns in transgenic rice plants. The results show that: WGA and PGA are both inducible by elicitors of Pyricularia oryzae in transgenic rice cells; the intron I of rice Act1 gene is important for the heterogenic expression of monocot and dicot promoter elements in rice; and the Act1 minimal promoter and its 5’untranslated leader sequence produced low level background expression in rice.展开更多
基金Supported by the National Natural Science Foundation of China(30370969,30230240)the Century-Across Excellent Talent Foundation(Jiaokehan 2002,No.48)the State Key Basic Research and Development Plan of China(2003CB114204)
文摘Harpins are bacterial proteins that can enhance plant growth and defense against pathogens and insects. To elaborate whether harpins perform the diverse functions in coordination with the activation of specific promoters that contain particular elements, we cloned pathogen-inducible plant promoters PPP1, PPP2, and PPP3 from tobacco and investigated their responses to harpinxoo or its truncated fragments DEG, DIR, and DPR (domains for enhancing plant growth, insect resistance and pathogen resistance). PPP1 contains an internal repeat composed of two tandem 111bp fragments; 111bp in the repeat was deleted in PPP2. PPP3 contains a bacteria-inducible element; PPP1 and PPP2 additionally contain TAC-1 and Eli boxes inducible correspondingly by salicylic acid (SA) and elicitors. Function of cloned PPPs was confirmed based on their activation in transgenic Arabidopsis plants by Ralstonia solanacearum (Ralston) or SA. Harpinxoo, DEG, DIR, or DPR activated PPP1 and PPP2 but not PPP3, consistent with the presence of Eli boxes in promoters. PPP1 was ca. 3-fold more active than PPP2, suggesting that the internal repeat affects levels of the promoter activation.
文摘To engineer crop disease resistance by utilizing natural defense mechanism that was expressed in the incompatible host-pathogen interactions is expected to result in a durable and broad-spectrum resistance. In order to prove this viewpoint, we amplified the coding region of the glucose oxidase (GO) gene from Aspergillus nigervia PCR and fused it to the pathogen-inducible promoter, Prp1-1. The chimeric gene was cloned into a plant expression vector and conjugated into Agrobacterium. Twenty-three transgenic potato plants were obtained by Agrobacterium-mediated transformation. The integration of GO gene was confirmed by Southern hybridization and the GO gene expression was identified with Kl-starch color reaction. Phytophthora infestans inoculation revealed that the expression of the chimeric transgene was induced by pathogen infection. Most of the transgenic plants exhibited various degrees of enhanced disease resistance. Four of them had lesion sizes reduced to less than half of the non-transgenic
基金supported by the National Natural Science Foundation of China(grant no.32372514)the Research and Innovation Initiatives of WHPU(grant no.2024J02)+1 种基金Y.L.(202108280009)was funded by the China Scholarship Councilsupported by BARD(grant no.5261-20C)to A.S and T.M.
文摘Botrytis cinerea is a major necrotrophic pathogen responsible for significant crop losses worldwide.Alternative strategies to control B.cinerea are urgently needed to reduce dependence on chemical fungicides,which are increasingly ineffective due to resistance and pose environmental risks.In this study,we identified two immunogenic epitopes derived from the B.cinerea cell death-inducing protein BcCrh1 and used them to engineer disease-resistant plants through a novel,spatially compartmentalized dual-epitope immune activation strategy.The first epitope is derived from a 35-amino acid intracellular peptide that exhibits both immunogenicity and cell death-inducing activity,which was mutated to separate these two properties.The second peptide represents an immunogenic portion of the protein that activates extracellular plant immunity.Transcriptomic and metabolomic analyses revealed that these epitopes trigger complementary defense pathways,and their co-expression integrates these responses into a robust,multilayered immunity,providing significantly enhanced protection compared with individual expression.Although constitutive expression of two epitopes conferred resistance,it also led to growth penalties.In contrast,pathogen-inducible expression of two epitopes preserved normal plant development while maintaining strong resistance to both B.cinerea and Pseudomonas syringae in Arabidopsis and tomato.This inducible strategy offers a major advantage by minimizing fitness costs while maximizing protection,highlighting the potential of spatially and temporally targeted epitope-based immune activation for durable and sustainable crop protection.
文摘The promoter fragments of wheat GstA1 and potato Gst1 have been amplified by PCR, cloned and fused respectively to the minimal promoter sequence of rice actin gene (Act1)) and its 5’ untranslated leader sequence together with GUS. The constructs with 2 chimeric promoters (WGA and PGA) have been transferred into rice in order to analyze their inducibility patterns in transgenic rice plants. The results show that: WGA and PGA are both inducible by elicitors of Pyricularia oryzae in transgenic rice cells; the intron I of rice Act1 gene is important for the heterogenic expression of monocot and dicot promoter elements in rice; and the Act1 minimal promoter and its 5’untranslated leader sequence produced low level background expression in rice.
