Characteristic Analysis And Preliminary Functional Identification Of Transcription Factor PeMYB2Gene In Phyllostachys Eduliss

Plant growth and crop productivity is influenced by the major abiotic stresses of drought, salinity andextreme temperatures. Transcription factors (TFs) play important roles in response to abiotic stresse andregulate the expression of many stress-related genes in plants. The MYB transcription factor is one ofthe largest families in plant transcription factors, which play important roles in response to abioticstresse in plants. The preliminary functions of PeMYB2are showed in this research, the results are asfollowing:(1)RT-PCR was used to analyze the expression pattern of PeMYB2under the cold, drought, NaCl andABA stresses, which showed that PeMYB2functions as a positive regulator to mediate tolerance inphyllostachys edulis to cold and salt stress; and that PeMYB2is involved in the ABA signal transductionpathway.(2)Chromosome walking, TAIL-PCR, was used to isolated promoters region of PeMYB2, whichcontained1457nucleotides, containing the core components of MYB, MBS, cryogenic response coreelement, LTR, drought-resistant core element, DRE and WRKY, abscisic acid response core element,ABRE, the jasmonic acid response core element, CGTCA-motif, salicylic acid response core element,TCA-motif, and the gibberellin response core element, P-box.(3)Yeast one-hybrid assays showed that PeMYB2can activate LacZ transcription, and thetransactivation activity was localized in its C-terminal regions. This result explained that PeMYB2wasa transcription activator and a positive transcription factor.(4) Construction of recombinant full length PeMYB2gene in the expression vectors were transformedinto Escherichia coli Rosetta (DE3) cells. The results of protein expression showed PeMYB2proteinwas insoluble in DE3cells, but the DNA domain of PeMYB2protein was partially soluble. In addition,PeMYB2protein in E. coli cells could offer protection against high salt, which further demonstrated thatPeMYB2related to salt tolerance.(5)Over-expressing PeMYB2in Arabidopsis thaliana had stronger tolerance to saline and coldstresses than wild type. Furthermore, expression analysis of salt stress response marker genes intransgenic and wild-type plants under stress condition indicated that PeMYB2regulated the expressionof NXH1、SOS1、RD29A、COR15A.In conclusion, bamboo transcription factor, PeMYB2, plays an important role in abiotic stress.