Functional analysis of apoplastic peroxidase Swpa4 in transgenic sweetpotato
The secretory class Ⅲ peroxidases (POD,EC 1. 11. 1.7) have been implicated in a broad range of physiological processes, including defense against pathogenic attack and a variety of abiotic stress tolerances. We previously characterized 13 POD cDNA clones from cell cultures and fibrous roots of svveetpotato (Ipomoea batatas). Among them,the expression of the swpaA gene was profoundly induced by a variety of abiotic stresses and pathogenic infections in sweetpotato. Additionally we demonstrated that the overexpression of apoplastic swpaA in transgenic tobacco plants showed tolerance to a variety of abiotic and biotic stresses. In this study,for a better understanding of the roles of swpaA, transgenic sweetpotato plants expressing swpaA under the control of CaMV 35S promoter were successfully generated by overxpression or knockdown. SwpaA transgenic sweetpotato plants with 22 overexpression and 17 knock-down lines generated by Agrobacterium-mediated transformation were characterized. The integration and gene expression levels of the constructs in the transformed plants were confirmed by genomic PCR,RT-PCR and POD assay. The swpaA overexpressing sweetpotato plants exhibited an approximately 10-fold higher POD activity than was observed in the control plants, whereas the swpaA suppressed plants showed an approximately 50％ lower POD activity than control plants. For further study,the transgenic plants will be characterized in terms of their response to environmental stress and agronomical characters including development of tuberous root. We also expect that functional analysis of apoplastic POD genes using the overexpression or knock-down plants is helpful in understanding the exact functions of apoplastic swpa4,and provides us valuable information on the development of tolerant crops to multiple various stresses.
apoplastic peroxidase environmental stress sweetpotato transgenic plant
KIM Yun-Hee LEE Haeng-Soon KWAK Sang-Soo
Environmental Biotechnology Research Center,Korea Research Institute of Bioscience and Biotechnology,Daejeon 305-806,Korea
国际会议
徐州
英文
72-78
2010-11-27（万方平台首次上网日期，不代表论文的发表时间）