TaMYB29: A Novel R2R3-MYB Transcription Factor Involved in Wheat Defense Against Stripe Rust

• Published in: Frontiers in plant science Vol. 12; p. 783388
• Main Authors: Zhu, Xiaoxu, Li, Xiang, He, Qi, Guo, Dongxiao, Liu, Caiqi, Cao, Junying, Wu, Zhongyi, Kang, Zhensheng, Wang, Xiaojing
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 29.11.2021
• Subjects: hypersensitive response; Plant Science; reactive oxygen species; stripe rust; TaMYB29; transcription factor; VIGS; hypersensitive response; TaMYB29; transcription factor; stripe rust; VIGS; reactive oxygen species
• ISSN: 1664-462X; 1664-462X
• DOI: 10.3389/fpls.2021.783388

Members of the R2R3-MYB transcription factor superfamily have been implicated in plant development, improved disease resistance, and defense responses to several types of stresses. To study the function of TaMYB29 transcription factor-a member of the R2R3-MYB superfamily-in response to an avirulent race of stripe rust pathogen, f. sp. ( ), we identified and cloned the gene from wheat cultivar (cv.) AvS+ following infection with . The TaMYB29 protein, comprising 261 amino acids, contains two highly conserved MYB domains. We first showed that TaMYB29 is a transcription factor, whose transcriptional levels are significantly induced by salicylic acid (SA), abscisic acid (ABA), jasmonic acid (JA), ethylene (ET), and . The results showed that TaMYB29 is involved in the wheat response to stipe rust. The overexpression of the gene resulted in the accumulation of reactive oxygen species (ROS) and pathogen-independent cell death in leaves. The silencing of gene in wheat cv. AvS+ , containing the stripe rust resistance gene , promoted hyphae growth, significantly downregulated the expression of pathogenesis-related ( ) genes, and substantially reduced the wheat resistance to compared with the non-silenced control. In addition, the accumulation of hydrogen peroxide (H O ) significantly decreased, and the activity of catalase, an enzyme required for H O scavenging, was elevated. Altogether, TaMYB29 positively regulates the defense response against stripe rust in wheat AvS+ by enhancing H O accumulation, gene expression, and SA signaling pathway-induced cell death. These results provide new insights into the contribution of TaMYB29 to the defense response against rust pathogens in wheat.