Overexpression in transgenic tobacco reveals different roles for the rice homeodomain gene OsBIHD1 in biotic and abiotic stress responses.
The rice OsBIHD1 gene encodes a transcriptional factor belonging to the homeodomain class. It had previously been shown to be activated by treatment with benzothiadiazole, a chemical inducer of disease resistance, and in an incompatible interaction between rice and the blast fungus. To allow a better understanding of the function of OsBIHD1 in plant disease resistance response, the OsBIHD1 gene in tobacco was overexpressed by Agrobacterium-mediated leaf disc transformation with a construct containing the OsBIHD1 ORF under control of the 35S promoter. Overexpression of the rice OsBIHD1 gene in some of the transgenic tobacco lines led to some morphological abnormalities in the top buds and roots. The transgenic tobacco plants showed an elevated level of defence-related PR-1 gene expression and enhanced disease resistance against infection by tomato mosaic virus, tobacco mosaic virus, and Phytophthora parasitica var. nicotianae. However, the transgenic tobacco plants overexpressing OsBIHD1 showed enhanced sensitivity to salt and oxidative stress as compared with the wild-type plants. The results suggested that the OsBIHD1 protein may be positively involved in activating expression of the defence-related genes in disease resistance responses, and is also important in rice development and abiotic stress tolerance.
Luo
Hongli
H
Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang 310029, PR China.
Song
Fengming
F
Zheng
Zhong
Z
D005638:Fruit; D015870:Gene Expression; D020022:Genetic Predisposition to Disease; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism*; D012275:Oryza / Q000235:genetics*; D018384:Oxidative Stress; D010641:Phenotype; D010935:Plant Diseases; D018515:Plant Leaves; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism*; D018517:Plant Roots; D010942:Plant Viruses; D030821:Plants, Genetically Modified; D012965:Sodium Chloride / Q000633:toxicity; D014026:Nicotiana / Q000187:drug effects / Q000235:genetics / Q000378:metabolism* / Q000821:virology
D018398:Homeodomain Proteins; D010940:Plant Proteins; D012965:Sodium Chloride