Open AccessWRKY Transcription Factors Actively Respond to Fusarium oxysporum in Lilium regale
Author(s) -
Shan Li,
Guanze Liu,
Limei Pu,
Xuyan Liu,
Zie Wang,
Qin Zhao,
Hongjun Chen,
Feng Ge,
Diqiu Liu
Publication year - 2021
Publication title -
phytopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.264
H-Index - 131
eISSN - 1943-7684
pISSN - 0031-949X
DOI - 10.1094/phyto-10-20-0480-r
Subject(s) - wrky protein domain , biology , fusarium oxysporum , methyl jasmonate , gene , ethephon , gene expression , nicotiana tabacum , genetics , botany , transcriptome , biochemistry , ethylene , catalysis
The WRKY transcription factors form a plant-specific superfamily important for regulating plant development, stress responses, and hormone signal transduction. In this study, many WRKY genes (LrWRKY1–35) were identified in Lilium regale, which is a wild lily species highly resistant to Fusarium wilt. These WRKY genes were divided into three classes (I to III) based on a phylogenetic analysis. The Class-II WRKY transcription factors were further divided into five subclasses (IIa, IIb, IIc, IId, and IIe). Moreover, the gene expression patterns based on a quantitative real-time PCR analysis revealed the WRKY genes were differentially expressed in the L. regale roots, stems, leaves, and flowers. Additionally, the expression of the WRKY genes was affected by an infection by Fusarium oxysporum as well as by salicylic acid, methyl jasmonate, ethephon, and hydrogen peroxide treatments. Moreover, the LrWRKY1 protein was localized to the nucleus of onion epidermal cells. The recombinant LrWRKY1 protein purified from Escherichia coli bound specifically to DNA fragments containing the W-box sequence, and a yeast one-hybrid assay indicated that LrWRKY1 can activate transcription. A co-expression assay in tobacco (Nicotiana tabacum) confirmed LrWRKY1 regulates the expression of LrPR10-5. Furthermore, the overexpression of LrWRKY1 in tobacco and the Oriental hybrid ‘Siberia’ (susceptible to F. oxysporum) increased the resistance of the transgenic plants to F. oxysporum. Overall, LrWRKY1 regulates the expression of the resistance gene LrPR10-5 and is involved in the defense response of L. regale to F. oxysporum. This study provides valuable information regarding the expression and functional characteristics of L. regale WRKY genes.