Zhixiang Chen

Professor

Department: Botany and Plant Pathology
Phone: 765.494.4657
Fax: 765.494.0363
Office: Whistler Hall, Room B026
E-mail: zhixiang@purdue.edu

Area of Expertise: Molecular Plant-Pathogen Interactions - Molecular basis of plant disease resistance; regulation of gene expression and signal transduction during plant defense responses to microbial pathogens.

Plants are constantly exposed to microbial pathogens and through evolution have developed a battery of defense mechanisms for combating microbial diseases. The major research interest of our group is to decipher the regulatory network of plants defense responses. Transcriptional regulation of plant host genes is a central part of plant defense response and elucidating the complex regulatory mechanisms for the differential expression of plant genes holds the key to our understanding of the molecular basis of plant disease resistance. We are studying a family of plant transcription factors containing the novel WRKY zinc-finger DNA-binding motifs. WRKY transcription factors are found only in plants and are encoded by a large gene family with more than 70 members in Arabidopsis. A majority of the WRKY genes in Arabidopsis are rapidly induced upon pathogen infection, suggesting a major function of the gene family in plant defense responses. We are using both genetic and molecular approaches to understand the regulation and biological functions of plant WRKY genes in plant defense responses.

In addition, we are studying posttranscriptional gene regulation and its roles in plant antiviral defense. Many eukaryotic organisms contain a group of novel RNA-dependent RNA polymerases (RdRPs) that synthesize small complementary RNAs (cRNAs) using cellular or viral RNA as templates. Certain members of RdRPs have recently been shown to be required for dsRNA-mediated gene silencing (RNA interference, RNAi). Recently we have identified a new plant RdRP that is induced by viral infection and defense-inducing compounds such as salicylic acid. Plants deficient in the inducible RdRP activity become more susceptible to viral pathogens. We are interested in further understanding the biological functions of plant RdRPs and elucidating their action mechanisms in antiviral defense and RNAi.

Publications

- Recent Publications

Mao, G., Meng, X., Liu, Y., Zheng, Z., Chen, Z., & Zhang, S. (2011). Phosphorylation of a WRKY transcription factor by two pathogen-responsive MAPKs drives phytoalexin biosynthesis in Arabidopsis. Plant Cell, 23, 1639-1653.

Lai, Z., Li, Y., Wang, F., Cheng, Y., Fan, B., Yu, J. Q., & Chen, Z. (2011). Arabidopsis sigma factor-binding proteins are coactivators of WRKY33 transcription factor in defense against necrotrophic pathogens. Plant Cell, 23, 3824-3841.

Cui, J. X., Zhou, Y. H., Ding, J. G., Xia, X. J., Shi, K., Chen, S. C., . . . Yu, J. Q. (2011). Role of nitric oxide in hydrogen peroxide-dependent induction of abiotic stress tolerance by brassinosteroids in cucumber. Plant Cell Environment, 34, 347-358.

Lai, Z., Wang, F., Zheng, Z., Fan, B., & Chen, Z. (2011). A critical role of autophagy in plant resistance to necrotrophic fungal pathogens in Arabidopsis. Plant Journal, 66, 953-968.

Chen, H., Lai, Z., Shi, J., Xiao, Y., Chen, Z., & Xu, X. (2010). Roles of Arabidopsis WRKY18, WRKY40 and WRKY60 transcription factors in plant responses to abscisic acid and abiotic stress. BMC Plant Biology, 10, 281.

Huang, J., Gu, M., Lai, Z., Fan, B., Shi, K., Zhou, Y., . . . Chen, Z. (2010). Functional analysis of the Arabidopsis PAL gene family in plant growth, development and response to environmental stress. Plant Physiology, 153, 1526-1538.

Xia, X., Chen, Z., & Yu, J. (2010). ROS mediate brassinosteroids-induced plant stress responses. Plant Signaling & Behavior, 5, 532-534.

Liu, D., Song, Y., Chen, Z., & Yu, D. (2009). Ectopic expression of miR396 suppresses GFR target gene expression and alters leaf growth in Arabidopsis. Physiologia Plantarum, 136, 223-238.

Zheng, Z., Qualley, A., Fan, B., Dudareva, N., & Chen, Z. (2009). An important role of a novel BAHD acyl transferase-like protein in plant innate immunity. Plant Journal, 57, 1040-1053.

Xia, X., Wang, Y., Asami, T., Chen, Z., & Yu, J. (2009). Reactive oxygen species plays a crucial role in brassinosteroids-induced stress tolerance in Cucumis sativus. Plant Physiology, 150, 801-814.

+ Patents

- Awards & Honors

Changjiang Visiting Professor (2010). Zhejiang University, China.

Guangbiao Visiting Professor (2009). Zhejiang University, China.

2006 Distinguished Alumi Award (2006). University of Nebraska-Lincoln.

+ News Releases

Released	URL	Source
9/1/2007	Plant virus sheds light on HIV	Agricultures Magazine
7/30/2007	Discovery in plant virus may help prevent HIV and similar viruses	University News Service
7/1/2003	Standing Tall	Agricultures Magazine