Cloning And Expression Analysis Of CiMYB68from Caragana Intermedia

Transcriptional regulation of defensive gene expression is a crucial part of plant defense responses to environment stresses. As one of the largest plant transcription factor families, MYB transcription factors play an important role in plant stress tolerance. In this paper, a MYB68was cloned for the first time from Caragana intermedia and its primary function was analyzed. The concrete conclusions are as following:1. CiMYB68was cloned using RT-PCR and RACE technology from C. intermedia. The full length cDNA sequence and gDNA sequence was both1209bp. The full length ORF was852bp, and the protein deduced comprised284amino acids with a calculated molecular weight of31459.4Da, as well as an isoelectric point of8.95.2. The expression of the CiMYB68under different stresses was detected by real-time qRT-PCR analysis. The results showed that CiMYB68was up-regulated significantly after drought or cold treatment in C. intermedia seedlings.3. A promoter fragment of1458bp in length of CiMYB68was cloned.. It contains the basic promoter elements and cis-acting elements responsive to biotic and abiotic stresses.4. Binary vector p35S::CiMYB68was constructed and the homozygous transgenic Arabidopsis thaliana overexpressing CiMYB68had been obtained.5. CiMYB68-GFP fusion construct was transformend into protoplast for transient expression or was transformed into A. thaliana to get permanent transgenic lines. Flourescence observation under confocal laser scanning microscope confirmed that the GFP tagged CiMYB68was localized in the cell nucleus.