Analysis Of The Functional Characterization Of PsneIF5A2/4 Gene

Effect of plant eIF5A proteins in a variety of biological process is as everyone knows, such as protein synthesis regulation, translation elongation of mRNA turnover, programmed cell death, and stress tolerance etc.This study used PCR technology from Poplar (Populus simonii×P. nigra) was cloned into the two eukaryotic translation initiation factor cDNA (Eukaryotic translation initiation in leaves of factor 5A) gene (eIF5A2/4). Through sequence analysis, we found that poplar eIF5A2/4 and eIF5Al genes are the orthologues in Arabidopsis. The deduced amino acid sequence of these two gene sequence showed 98% similarity to each other. The subcellular localization analysis results showed that the PsneIF5A2/4 protein is localized to the nucleus and the cytoplasm. The qRT-PCR analysis of the expression pattern of PsneIF5 A2/4 in different tissues of poplar show that these two genes are transcribed in all poplar tissue samples. The eIF5A2/4 was ligated in the yeast expression vector pYES2-eIF5A2/4 andtransformed into yeast(Saccharomyces cerevisiae) of uracil auxotrophic strains INVScl. PCR and Northern blot results confirmed that the expression of eIF5A2/4 could be induced by galactose in obtained transgenic strains. The growth comparison of transgenic strains and no-load strains under NaCl stresses showed that under the abiotic stress transgenic strain showed higher survival colony number than that of non transgenic strains, suggesting that the eIF5A2/4 gene improved stress resistance of transgenic yeast. In addition, transgenic Arabidopsis thaliana, obtained by Agrobacterium-mediated method, overexpressing PsneIF5A2 showed enhanced SOD, POD activity, reduced the copper sulfate and MDA and electrolyte leakage under salt stress.