Exression Analysis Of Rice Gene OsSsr1and Primary Function Analysis Of Rice Gene Os02g0198200

Hrfl could encode Harpin protein of Xanthomonas oryzae pv. oryzae. We transformed hrfl into R109and obtained the transgenic rice NJH12. Our laboratory preliminary studies showed that the transgenic line NJH12could improve resistance of rice to Magnaporthe grisea, Xanthomonas oryzae and drought. The expression microarray data of NJH12was analyzed and obtained a large number of up-regulated genes.OsSsrl gene（Oryza sativa L. salt-sensitive related gene1, GenBank accession: NM₀01065574） was one of the up-regulated genes of NJH12expression profiling.. To further analyze the encoding sequence, promoter sequence, subcellular localization and expression pattern of rice OsSsrl, bioinformatics methods, subcellular localization, RiceXPro database and Real-time PCR were used to study this gene. The sequence analysis showed that OsSsrl consisted of an ORF with a length of2004bp, encoded a667amino acids protein containg five transmembrane regions, and also contained a signal peptide in the N-terminal domain. The promoter sequence contained several stress-related cis-acting elements, such as TGACG-motif, ABRE, TCA-element, W box. The expression of OsSsrl-GFP fusion protein suggested that OsSsrl protein mainly appeared in cell membrane. The analysis of expression data in RiceXPro database revealed that OsSsrl was expressed in rice different tissues, but the highest expression level was in leaf and root, the lowest was in embryo. The Real-time PCR analysis indicated that OsSsrl was up-regulated under kinds of environmental stimulus, including drought, drought, high temperature, high salt, low temperature, wound, Magnaporthe grisea, MeJA and ABA.Os02g0198200gene was also one of the up-regulated genes of NJH12expression profiling. The sequence analysis of Os02g0198200showed that Os02g0198200consisted of two EF-hand motifs and encoded an EF-hand calcium binding protein. In this study, The silencing vector pVec8::HAB of Os02g0198200was successfully built. Calli from mature embryos of rice cultivar Oryza sativa L. subsp. Japonica precultured were infected and transformed by Agrobacterium tumefaciens strain EHA105/pVec8::Os02g0198200and EHA105/pVec8::HAB. Hpt was used as resistance screening,19strains of overexpression plant and21strains of silcening plant were obtained. The PCR test showed that Os02g0198200had been integrated into the rice genome; The RT-PCR indicated that Os02g0198200could express normally in transgenic rice. Analysis of TO generation transgenic plant to Xanthomonas oryzae pv. Oryzae（PXO99） shown that overexpression of Os02g0198200enhanced resistance to Xanthomonas oryzae at the booting stage, different lines of transgenic rice had different resistance and silcening of Os02g0198200could not increase the susceptibility to Xanthomonas oryzae. In Xoo-uninfected condition, the expression of defense response-related genes influenced. The result indicated that the overexpression of Os02g0198200might activate expression of defense response-related genes and the resistance to Xoo of overexpression lines might be related to the activation of defense response-related genes.