Expression Of Pathogenesis-Related Proteins In The Interactions Between Rice And Xanthomonas Oryzae Pv. Oryzae

Background:Rice (Oryza sativa L.) is an important crop, is the staple food of more than half the world’s population. Rice is often affected by fungi, bacteria,viruses and nematodes. When the plant is stressed by the biotic and abiotic, it can induce and accumulation a class of proteins, the proteins are pathogensis-related (PR) proteins. Such proterins play an important role in the downstream of plant disease resistance reactions. Currently, the sequencing of the rice has been completed, understanding the function of the protein in rice will become an important part of biological research. Researching the expression features of protein in the interaction between rice and bacterial blight is important to identify the molecular mechanisms of disease mediated by the resistance genes.Aim:The expression profiling and functional characterization of pathogenesis-related (PR) protein will be helpful to understand the mechanism of rice disease resistance.Material and methods:To better understand the function of PR proteins, ten differentially transcripted PR genes identified in our previous work using whole genome rice microarray were selected. Western blotting (WB) analysis were used to survey the expression profile in normal growth leave and rice-Xanthomonas oryzae pv. oryzae (Xoo) interactions.Results:The results indicated that the expression of Osl2g43380, Osl2g36830, Osl2g36860, Osl2g36840, Os02g41670, Os05g35290and Os12g33610increased gradually during leave growth, reached the highest peak at flowering stage and decreased slightly at mature stage. In rice-Xoo interactions, the expression of Os01g51570, Os01g71680and Os12g36850were up-regulated and the expression of Osl2g36830, Os12g36840, Os02g41670and Os05g35290were down-regulated. It is interesting to note that the expression pattern of PR proteins was similar in both compatible and incompatible rice-Xoo interactions. In addition, cis-elements analysis of the promoter region of PR genes revealed possible defense-related cis-elements, ARE, HSE, MBS and TC-rich repeats were found more frequently in the upstream region of defense-related PR genes.Conclusion:The experimental results revealed that the expression of PR proteins is relevant to the resistance between rice and Xanthomonas oryzae pv. Oryzae(Xoo), laid a solid foundation for the further research the function of PRs.