CmWRKY15 Facilitates Alternaria tenuissima Infection of Chrysanthemum

PLoS One. 2015 Nov 24;10(11):e0143349. doi: 10.1371/journal.pone.0143349. eCollection 2015.

Abstract

Abscisic acid (ABA) has an important role in the responses of plants to pathogens due to its ability to induce stomatal closure and interact with salicylic acid (SA) and jasmonic acid (JA). WRKY transcription factors serve as antagonistic or synergistic regulators in the response of plants to a variety of pathogens. Here, we demonstrated that CmWRKY15, a group IIa WRKY family member, was not transcriptionally activated in yeast cells. Subcellular localization experiments in which onion epidermal cells were transiently transfected with CmWRKY15 indicated that CmWRKY15 localized to the nucleus in vivo. The expression of CmWRKY15 could be markedly induced by the presence of Alternaria tenuissima inoculum in chrysanthemum. Furthermore, the disease severity index (DSI) data of CmWRKY15-overexpressing plants indicated that CmWRKY15 overexpression enhanced the susceptibility of chrysanthemum to A. tenuissima infection compared to controls. To illustrate the mechanisms by which CmWRKY15 regulates the response to A. tenuissima inoculation, the expression levels of ABA-responsive and ABA signaling genes, such as ABF4, ABI4, ABI5, MYB2, RAB18, DREB1A, DREB2A, PYL2, PP2C, RCAR1, SnRK2.2, SnRK2.3, NCED3A, NCED3B, GTG1, AKT1, AKT2, KAT1, KAT2, and KC1were compared between transgenic plants and controls. In summary, our data suggest that CmWRKY15 might facilitate A. tenuissima infection by antagonistically regulating the expression of ABA-responsive genes and genes involved in ABA signaling, either directly or indirectly.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abscisic Acid / pharmacology
  • Alternaria*
  • Chrysanthemum / classification
  • Chrysanthemum / drug effects
  • Chrysanthemum / genetics*
  • Chrysanthemum / microbiology*
  • Gene Expression Regulation, Plant / drug effects
  • Genetic Predisposition to Disease*
  • Intracellular Space
  • Phenotype
  • Phylogeny
  • Plant Diseases / genetics*
  • Plant Diseases / microbiology*
  • Plant Proteins / genetics*
  • Plants, Genetically Modified
  • Protein Transport
  • Stress, Physiological / genetics
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Transcriptional Activation

Substances

  • Plant Proteins
  • Transcription Factors
  • Abscisic Acid

Grants and funding

This study was funded by the National Natural Science Foundation of China (31471913, 31301809), the National Science Fund for Distinguished Young Scholars (31425022), the Fundamental Research Funds for the Central Universities (KYTZ201401), Special Fund for Agro-scientific Research in the Public Interest (201403039), the Six Talent Peaks Project in Jiangsu Province (2013-NY-022), and the China Postdoctoral Science Foundation (2014M561673, 2015T80564).