title: SpMYB overexpression in tobacco plants leads to altered abiotic and biotic stress responses.
abstract: The MYB transcription factors are involved in various plant biochemistry and physiology processes and play a central role in plant defense response. In the present study, a full-length cDNA sequence of a MYB gene, designated as SpMYB, was isolated from tomato. SpMYB encodes the R2R3-type protein consisting of 328 amino acids. The expression level of SpMYB was strongly induced by fungal pathogens. Transgenic tobacco plants overexpressing SpMYB had an enhanced salt and drought stress tolerance compared with wild-type plants, and showed significantly improved resistance to Alternaria alternate. Further analysis revealed that transgenic tobaccos exhibited less accumulation of malondialdehyde (MDA) and more accumulation of superoxide dismutase (SOD), peroxidase (POD) and phenylalanine ammonia-lyase (PAL) after inoculation with A. alternate. Meanwhile, changes in some photosynthetic parameters, such as photosynthetic rate (Pn), transpiration rate (Tr) and intercellular CO2 concentration (Ci) were also found in the transgenic tobaccos. Furthermore, transgenic tobaccos constitutively accumulated higher levels of pathogenesis-related (PR) gene transcripts, such as PR1 and PR2. The results suggested that the tomato SpMYB transcription factor plays an important role in responses to abiotic and biotic stress.
authors: School of Life science and Biotechnology, Dalian University of Technology, Dalian 116024, China.
authors: Jing-Bin
authors: JB
authors: Li
authors: School of Life science and Biotechnology, Dalian University of Technology, Dalian 116024, China. Electronic address: ysluan@dlut.edu.cn.
authors: Yu-Shi
authors: YS
authors: Luan
authors: School of Life science and Biotechnology, Dalian University of Technology, Dalian 116024, China.
authors: Ya-Li
authors: YL
authors: Yin
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D017931:DNA Primers; D017343:Genes, Plant; D008969:Molecular Sequence Data; D020626:Oncogene Proteins v-myb / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D030821:Plants, Genetically Modified; D060888:Real-Time Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013312:Stress, Physiological / Q000235:genetics*; D014026:Nicotiana / Q000235:genetics* / Q000502:physiology
chemical_list: D017931:DNA Primers; D020626:Oncogene Proteins v-myb
keywords: Abiotic and biotic stress; MYB transcription factor; Tobacco; Tomato