Characteristics Analysis Of Wheat DREB And EREBP Transcription Factor

Plants are exposed to abiotic environmental stress such as drought, high salt and low temperature, which cause adverse effect on the growth and development of the plant. Plants response to the stress by initiating the signal transduction pathway and inducing the transcription and expression of the gene. The transcription factor plays an important role on transcriptional control.A fusion expression cDNA library were constructed and several gene such as W23 W18 W17 were cloned. Bioinformational analysis show that all these genes includes a AP2/EREBP DNA binding domain which belongs to the AP2 transcriptional factor family.W23 and W18 belong to the DREB family; W17 belongs to the EREB family. Based on the work done, the EMS A and the transactivation experiments have been done to study the characteristic of the transcription factor which they encode, further for transgenic analysis and study of control mechanism in signal transduction pathway.The EMSA indicated that W23 and W18 can bind to the DRE probe; W17 can bind to the GCC probe. Binding to the mutant probe lead to the band getting weak or disappeared. This indicated that they bind to the cis-element specifically and belong to the DREB and EREB family respectively. Furthermore we get the information about the important base in the cis-element.For proving the characteristic of the transactivation of the transcriptional factor , we transformed the constructed expression vector into the yeast reporter which has the DRE and GCC cis-element . the result revealed that these transcription factor not only have the DNA binding domain but also have the transactivational ability. Their transactivational ability is different. The transcription factor has the conserved DNA binding domain but the different transactiation domain.The DREBs bind to the DRE cis-element whose core sequence is CCGAC; the EREBPs bind to the ERE cis-element whose core sequence is GCCGCC. The two sequence is very similar in common in CCGNC. But they are controled in different pathway . which downstream genes they control and by which upstream gene they induced, all the question need to be further solved.