Transcriptional Characteristics of Xa21-mediated Defense Responses in Rice

Qiang Gan, Hui Bai, Xianfeng Zhao, Yong Tao, Haipan Zeng, Yuning Han, Wenyuan Song, Lihuang Zhu, Guozhen Liu
Journal of Integrative Plant Biology, 2011, 53(4): 300-311  DOI: 10.1111/j.1744-7909.2011.01032.x     追溯原文......本站官方QQ群:62473826

Bacterial blight, caused by Xanthomonas oryzae pv. oryzae (Xoo), is the most destructive bacterial disease of rice. The cloned rice gene Xa21 confers resistance to a broad spectrum of Xoo races. To identify genes involved in Xa21-mediated immunity, a whole-genome oligonucleotide microarray of rice was used to profile the expression of rice genes between incompatible interactions and mock treatments at 0, 4, 8, 24, 72 and 120 h post inoculation (hpi) or between incompatible and compatible interactions at 4 hpi, respectively. A total of 441 differentially expressed genes, designated as XDGs (Xa21 mediated differentially expressed genes), were identified. Based on their functional annotations, the XDGs were assigned to 14 categories, including defense-related, signaling, transcriptional regulators. Most of the defense-related genes belonged to the pathogenesis-related gene family, which was induced dramatically at 72 and 120 hpi. Interestingly, most signaling and transcriptional regulator genes were downregulated at 4 and 8 hpi, suggesting that negative regulation of cellular signaling may play a role in the Xa21-mediated defense response. Comparison of expression profiles between Xa21- and other R gene-mediated defense systems revealed interesting common responses. Representative XDGs with supporting evidences were also discussed.

  白叶枯病抗性基因 Xa21; Xa-21