TITLE:
Genome Wide Transcriptomic Analysis of WRKY Gene Family Response to Biotic Stresses in Malus ×domestica
AUTHORS:
Hanghang Zhang, Liu Yang, Ruli Zhou, Yingli Zhang, Zhengyang Wang, Hongguang Pang, Tuanhui Bai, Shangwei Song, Jian Jiao, Miaomiao Wang, Jiancan Feng, Chunhui Song, Xianbo Zheng
KEYWORDS:
Apple, WRKY, Transcription Factor, Pathogens, Big Data
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.12 No.5,
May
28,
2021
ABSTRACT: Apple (Malus × domestica Borkh.) is a
perennial woody plant that often suffers from various biological stresses. Many
harmful pathogens can infect apple trees and lead to reduced production. We
comprehensively identified the WRKY genes in the apple genome and
analyzed their expression in response to several biological stressors,
including Alternaria alternata, Pythium ultimum, Botryosphaeria dothidea, Erwinia
amylovora, Penicillium expansum, Gymnosporangium yamadae, and Apple replant disease. There
were 113 MdWRKYs identified in the
apple genome. Twenty-two MdWRKYs were
differentially expressed in response to at least five pathogens. Promoter
sequence analysis showed that these genes carried many defense- and stress-responsive
elements, such as MeJA-response elements, salicylic acid-response elements, and
W-box elements, in their promoters. Transient expression assays showed that MdWRKY40a and MdWRKY54h played negative roles in defense
against B. dothidea infection. WRKY40 and WRKY60 and the MdWKRY33s might play important roles in
responding to pathogens and are conserved in some plants. These differentially
expressed MdWRKYs might play key
roles in the apple response to multiple pathogens.