Resistance Identification Of The Transgenic Arabidopsis Expressing TaBTF3 Transcription Factor

pWM101 vector was used to construct the overexpression vector of wheat transcription factor TaBTF3,and inserted into the Arabidopsis thaliana genome by using the dipping inflorescence,in which TaBTF3 was heterologously expressed in the genome of Arabidopsis thaliana.The transgenic Arabidopsis plants expressing TaBTF3 were identified via the hygromycin resistance screening with being combined with PCR selection.After being treated with 250 mM mannitol or 150 mM NaCl for 7 d,the Arabidopsis transgenic plants expressing TaBTF3 gene grew stronger than the wild-type plants.These indicated that the transcription factor TaBTF3 was positively related to the osmotic and salt stresses in plants.These phenotypic results were quantitatively confirmed by using the growth and physiological parameters.The survival rate,root lengths,fresh weights,and dry weights of the Arabidopsis transgenic plants expressing TaBTF3 gene were significantly higher than those of the wild Arabidopsis plants.Compared to the wild-type Arabidopsis plants,moreover,the contents of chlorophyll and proline in Arabidopsis transgenic plants expressing TaBTF3 gene significantly increased,while the contents of H2O2 and MDA remarkably decreased in these transgenic plants.These results suggested that the transcription factor TaBTF3 could enhance the osmotic and salt stress resistances in plants.To elucidate the molecular mechanism of the transcription factor TaBTF3 in osmotic and salt stresses,the transcription levels of six stress-responsive genes(RD29A、ABF3、LEA、DREB1A、KIN1 and P5CS)were measured using the qPCR in seedlings of the Arabidopsis transgenic plants expressing TaBTF3.Under the osmosis stress condition,the transcription levels of RD29A、ABF3、LEA、DREB1A、KIN1 and P5CS genes in the Arabidopsis transgenic plants expressing TaBTF3 gene were remarkably up-regulated and were significantly higher than those in wild-type plants,suggesting that these stress-responsive genes could be related to in osmotic stress tolerance induced by the transcription factor TaBTF3.These results implied that the transcription factor TaBTF3 can act as an important regulatory factor being involved in multiple pathways of abiotic stress responses in plants.