One novel osmotin promoter, binding_protein (OPBP1) gene, was isolated from salt adapted tobacco suspension cells using yeast one hybrid system. The OPBP1 interacted specifically in vivo with FA, a DNA sequence from t...One novel osmotin promoter, binding_protein (OPBP1) gene, was isolated from salt adapted tobacco suspension cells using yeast one hybrid system. The OPBP1 interacted specifically in vivo with FA, a DNA sequence from the 5′ upstream region of osmotin gene, which was essential for osmotin responsiveness. The deduced amino acid sequence of OPBP1 contained a conserved motif of a new gene family, AP2 family. This protein did not contain the typical motif found in the most known DNA binding proteins and transcription factors.展开更多
Plants are recurrently exposed to myriads of biotic and abiotic stresses leading to several biochemical and physiological variations that cause severe impacts on plant growth and survival.To overcome these challenges,...Plants are recurrently exposed to myriads of biotic and abiotic stresses leading to several biochemical and physiological variations that cause severe impacts on plant growth and survival.To overcome these challenges,plants activate two primary defense mechanisms,such as structural response(cell wall strengthening and waxy epidermal cuticle development)and metabolic changes,including the synthesis of anti-microbial compounds and proteins,especially the pathogenesis-related(PR)proteins.PR proteins are members of a super large family of defense proteins that exhibit antimicrobial activities.Their over-expression in plants provides tolerance to many abiotic and biotic stresses.PR proteins have been classified into 17 families,including PR-5–also called thaumatin-like proteins(TLPs)that involve osmotin and osmotin-like proteins(OLPs).Osmotin was first identified in tobacco(Nicotiana tabacum var.Wisconsin 38),and then its homolog proteins(OLPs)were reported from the whole plant kingdom.Osmotin and OLPs are ubiquitous in all fruits and vegetables.Their expression has been detected in various plant tissues and organs.The phylogenetic tree studies revealed that the osmotin group originated from spermatophytes.Moreover,the atomic structure of OLP has shown similarity to thaumatin and TLPs from monocot and eudicot species,which determines a strong evolutionary pressure in flowering plants for conserving thaumatin fold.This is associated with the role of these proteins against pathogens as defense molecules and to induce stress tolerance to plants against several biotic and abiotic factors.In this review,we have briefly described the development history of osmotin,including its function and mechanism to induce biotic and abiotic stress tolerance to plants.展开更多
[ Objective] The FaOLtr2 （ Frago^ia ananassa osmotin-like protein） is a functional homolog of PR5-1ike protein. This study was undertaken to produce recombinant FaOLP2 and to identify its antifungal activity. [ Meth...[ Objective] The FaOLtr2 （ Frago^ia ananassa osmotin-like protein） is a functional homolog of PR5-1ike protein. This study was undertaken to produce recombinant FaOLP2 and to identify its antifungal activity. [ Method] The ORF of FaOLP2 （ accession number DQ325524） was cloned into pET22b vector to con- stroct the pET22b-FaOLP2 plasmid. The recombinant mature FaOLP2 was expressed in E. coli Rosetta-gami B （DE3） by inducing with I nunol/L IPTG and found exclusively in insoluble inclusion bodies. As FaOLP2 requires the correct formation of eight disulfide bonds, but there were no obvious effect to correctly form these by expression at different temperatures and high osmotic pressure （ supplemented Betaineand and D-Sorbitol）, we used an in vitro method to refold E. coli expressed FaOLP2 by gradually elution using reduced：oxidized gluthatione redox buffer, followed by 8 mol/L urea solubilized His6-tagged mature FaOLP2 protein, which was affinity-purified by an immobilized-metal （Ni2＋ ） affinity chromatography （IMAC） column. [ Result] This method generated biologically active conformations of the recombinant mature FaOLP2 that displayed antifungal activity against Ustilaginoides virens, a plant pathogenic fungus, which causes rice false smut. [ Conclusion] This study laid the foundation for further biotechnological application of the novel protein.展开更多
文摘One novel osmotin promoter, binding_protein (OPBP1) gene, was isolated from salt adapted tobacco suspension cells using yeast one hybrid system. The OPBP1 interacted specifically in vivo with FA, a DNA sequence from the 5′ upstream region of osmotin gene, which was essential for osmotin responsiveness. The deduced amino acid sequence of OPBP1 contained a conserved motif of a new gene family, AP2 family. This protein did not contain the typical motif found in the most known DNA binding proteins and transcription factors.
文摘Plants are recurrently exposed to myriads of biotic and abiotic stresses leading to several biochemical and physiological variations that cause severe impacts on plant growth and survival.To overcome these challenges,plants activate two primary defense mechanisms,such as structural response(cell wall strengthening and waxy epidermal cuticle development)and metabolic changes,including the synthesis of anti-microbial compounds and proteins,especially the pathogenesis-related(PR)proteins.PR proteins are members of a super large family of defense proteins that exhibit antimicrobial activities.Their over-expression in plants provides tolerance to many abiotic and biotic stresses.PR proteins have been classified into 17 families,including PR-5–also called thaumatin-like proteins(TLPs)that involve osmotin and osmotin-like proteins(OLPs).Osmotin was first identified in tobacco(Nicotiana tabacum var.Wisconsin 38),and then its homolog proteins(OLPs)were reported from the whole plant kingdom.Osmotin and OLPs are ubiquitous in all fruits and vegetables.Their expression has been detected in various plant tissues and organs.The phylogenetic tree studies revealed that the osmotin group originated from spermatophytes.Moreover,the atomic structure of OLP has shown similarity to thaumatin and TLPs from monocot and eudicot species,which determines a strong evolutionary pressure in flowering plants for conserving thaumatin fold.This is associated with the role of these proteins against pathogens as defense molecules and to induce stress tolerance to plants against several biotic and abiotic factors.In this review,we have briefly described the development history of osmotin,including its function and mechanism to induce biotic and abiotic stress tolerance to plants.
基金Supported by Zhejiang Province Natural Science Foundation(Y307591,Y3110288)Key Scientific and Technological Innovation Team Program of Zhejiang Province(2010R50028)
文摘[ Objective] The FaOLtr2 （ Frago^ia ananassa osmotin-like protein） is a functional homolog of PR5-1ike protein. This study was undertaken to produce recombinant FaOLP2 and to identify its antifungal activity. [ Method] The ORF of FaOLP2 （ accession number DQ325524） was cloned into pET22b vector to con- stroct the pET22b-FaOLP2 plasmid. The recombinant mature FaOLP2 was expressed in E. coli Rosetta-gami B （DE3） by inducing with I nunol/L IPTG and found exclusively in insoluble inclusion bodies. As FaOLP2 requires the correct formation of eight disulfide bonds, but there were no obvious effect to correctly form these by expression at different temperatures and high osmotic pressure （ supplemented Betaineand and D-Sorbitol）, we used an in vitro method to refold E. coli expressed FaOLP2 by gradually elution using reduced：oxidized gluthatione redox buffer, followed by 8 mol/L urea solubilized His6-tagged mature FaOLP2 protein, which was affinity-purified by an immobilized-metal （Ni2＋ ） affinity chromatography （IMAC） column. [ Result] This method generated biologically active conformations of the recombinant mature FaOLP2 that displayed antifungal activity against Ustilaginoides virens, a plant pathogenic fungus, which causes rice false smut. [ Conclusion] This study laid the foundation for further biotechnological application of the novel protein.
