Expression of Pinellia ternata leaf agglutinin under rolC promoter confers resistance against a phytophagous sap sucking aphid, Myzus persicae

Background: Piercing/sucking insect pests in the order Hemiptera causes substantial crop losses by removing photoassimilates and transmitting viruses to their host plants. Cloning and heterologous expression of plant-derived insect resistance genes is a promising approach to control aphids and other sap-sucking insect pests. While expression from the constitutive 35S promoter provides broad protection, the phloem-specific rolC promoter provides better defense against sap sucking insects. The selection of plant-derived insect resistance genes for expression in crop species will minimize bio-safety concerns. Results: Pinellia ternata leaf agglutinin gene ( pta ), encodes an insecticidal lectin, was isolated and cloned under the 35S and rolC promoters in the pGA482 plant transformation vector for Agrobacterium -mediated tobacco transformation. Integration and expression of the transgene was validated by Southern blotting and qRT-PCR, respectively. Insect bioassays data of transgenic tobacco plants showed that expression of pta under rolC promoter caused 100% aphid mortality and reduced aphid fecundity up to 70% in transgenic tobacco line LRP-9. These results highlight the better effectivity of pta under rolC promoter to control phloem feeders, aphids. Conclusions: These findings suggested the potential of PTA against aphids and other sap sucking insect pests. Evaluation of gene in tobacco under two different promoters; 35S constitutive promoter and rolC phloem-specific promoter could be successfully use for other crop plants particularly in cotton. Development of transgenic cotton plants using plant-derived insecticidal, PTA, would be key step towards commercialization of environmentally safe insect-resistant crops. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */\r\n table.MsoNormalTable\r\n\t{mso-style-name:\"Tabla normal\";\r\n\tmso-tstyle-rowband-size:0;\r\n\tmso-tstyle-colband-size:0;\r\n\tmso-style-noshow:yes;\r\n\tmso-style-priority:99;\r\n\tmso-style-parent:\"\";\r\n\tmso-padding-alt:0cm 5.4pt 0cm 5.4pt;\r\n\tmso-para-margin-top:0cm;\r\n\tmso-para-margin-right:0cm;\r\n\tmso-para-margin-bottom:8.0pt;\r\n\tmso-para-margin-left:0cm;\r\n\tline-height:107%;\r\n\tmso-pagination:widow-orphan;\r\n\tfont-size:11.0pt;\r\n\tfont-family:\"Calibri\",sans-serif;\r\n\tmso-ascii-font-family:Calibri;\r\n\tmso-ascii-theme-font:minor-latin;\r\n\tmso-hansi-font-family:Calibri;\r\n\tmso-hansi-theme-font:minor-latin;\r\n\tmso-bidi-font-family:\"Times New Roman\";\r\n\tmso-bidi-theme-font:minor-bidi;}