Studies On Cloning Of BebZIP And BeNRT Genes And Their Preliminary Function In Bambusa Emeiensis

Bambusa emeiensisis is an important species with the good fiber in south-western of China.It is widely used for making pulp.However,Bambusa emeiensis is susceptible to both abiotic or abiotic stress,which in turn causes a large area of production reduction in yield.Meanwhile,as a perennial gramineous plant,the degree of soil consolidation gradually increases and the soil nutrients content decreases as the cultivation period increases.Therefore,it is effective way to increase the yield of Bambusa emeiensis by improving the resistance to abiotic or abiotic stress and enhancing the ability of absorption and translocation of nutrient elements.bZIP is an important member of the transcription factor family and it has been well recognized that bZIP is mainly involved in the regulation of biotic or abiotic stresse.In addition,many studies have been reported that NRT are mainly involved in the absorption and utilization of nitrogen sources by plants.In this study,the two bZIP genes and one NRT gene were cloned from Bambusa emeiensis.The bioinformatics analysis of three genes were carried out,their yeast one-hybrid screening and subcellular localization analysis were performed.Consequently the overexpression vector of three genes were contructed and transformed into Populus tomentosa and phyllostachys edulis.The transgenic plants of Populus tomentosa was used for the response analysis to drought and low Nitrogen stress.The main results are as follows:The transcriptional self-activation activity of BebZIP4 and BebZIP6 was carried out by yeast one-hybridization.The results showed that both of them had the transcriptional self-activation activity,and their?-galactosidase activity was201 and 115 Miller,respectively.The subcellular localization analysis of BebZIP4 and BebZIP6 transcription factors showed that both of them were localized in the nucleus,which was consistent with the subcellular localization prediction.Based on the transcriptome database of bambusa emeiensis,the two bZIP genes?BebZIP4 and BebZIP6?and one NRT gene?Be NRT1?were selected and cloned successfully,their overexpression vectors of p CAMBIA 1303-N-BebZIP4,p CAMBIA 1303-N-BebZIP6,p CAMBIA 1303-N-Be NRT1 wereconstructed.They were transformed into Populus tomentosa by agrobacterium-mediated method.The 14 positive transgenic plants of BebZIP4 gene,13positive transgenic plants of BebZIP6 gene and 18 positive transgenic plants of Be NRT1 gene were obtained,respectively.The positive rate were 53.84%,48.15%and 43.90%,respectively.The BebZIP4 and Be NRT1 gene were transformed into the immature embryo of phyllostachys edulis by particle bombardment method.PCR analysis showed that one BebZIP4 transgenic plant and one Be NRT1 transgenic plant were obtained,respectively.The response of the transgenic plants from BebZIP4 and BebZIP6 genes to drought strss showed that the activities of SOD,CAT and POD and the content of proline in the transgenic plants decreased,while the content of MDA increased.This series of results showed that the tolerance of the transgenic plants of BebZIP4 and BebZIP6 genes to drought stress is lower,compared with CK.Compared with the wild-type Populus tomentosa,the transgenic plants of BebZIP4 and BebZIP6 genes are sensitive to drought stress,the transgenic plants of Be NRT1 gene are not sensitive to low-nitrogen stress,using in situ detection of H₂O₂.