Differential Gene Expression And Functional Analysis Of GmRNF12 And Gmfdr3underalstressinsoybean(Glycinemaxl.)

Soil acidification is an increasing problem in the world because of acid rain, intensive agriculture and with the excessive use of nitrogen fertilizers. Al toxicity is considered to be one of the most important limiting factors of crop production on acid soils. Under acidic conditions, toxic forms of Al will mobilized into soil solution, and rapidly inhibit plant root growth, subsequently decrease nutrient and water uptake, and result in poor crop growth and productivity. The ability to resist Al stress is different in genotypic differences among plant species or cultivars within the same species and the ability to resist Al stress is genetic. The identification and characterization of Al resistance genes will not only greatly advance our understanding of the mechanistic functioning of these processes, but,more importantly, will be the source of new molecular resources that researchers will use to develop improved crops better suited for cultivation on the acid soils that comprise such a large fraction of the world's lands.Using genomic microarray technique researched genes differential expression under Al stress in soybean and obtained a primary gene expression profiling and to undersand the Al resistance mechanism at global transaiptional level.The present study provided the genomic microarray analysis of soybean transcriptional responses under Al stress, in which the genomic transcriptional levels of Al-stressed soybean were analyzed using the Affymetrix porcine GeneChip. Total RNA was extracted from soybean tips collected before and after Al. Results showed that 639 genes were confirmed as having a greater than twofold altered expression, with 561up-regulated and 78down-regulated. 334 genes involved in a wide range of functions, but 305 genes (47.8% )are unknown functions .The functions of the 639 genes were observed by the Gene Ontology tool, available from the Affymetrix web.These clustered into 9 functional groups: cell wall related(5.9%), signal transduction(3.4%), kinase and phosphorylation(6.3%), Primary and secondary metabolism (5.6%),Oxidative reponse(7.2%), Resistance reponse(7.1%), transcription factor(9.2%),Transporter(4.2%),.Quantitative real-time PCR was used to verify the microarray data.Quantitative real-time PCR method detected the differential expression of some genes at different times under Al stress in jiyu70 and jiyu62. The results compared the difference of gene expression characteristics between in jiyu70 and jiyu62.By using RT-PCR technique, GmRNF12å’ŒGmFDR3 were isolated from soybean tips. The results of sequence functionally annotated by Blast in NCBI indicate GmRNF12 encodes a Zn-finger type transcription factor consisting of 236 amino acids. GmFDR3 encodes a MATE family protein consisting of 589 amino acids. Analysis of phylogenetic tree indicated that GmFDR3 is more closely related with LaFDR3.Real-time PCR technique was applied to clarify the express pattens response tovarious abiotic stresses about GmRNF12. GmRNF12 was induced by drought,salt , low-temperature ,SA and ABA . GmFDR3 was induced by SA.Two overexpression vectors for two genes were construced and transfornled into Arabidopsis by Agrobacterium-mediated transformation. Identification of Al resistance indicated that the T3 generation of transgenic Arabidopsis plants showed increasing resistance to Al.