AUTHOR=Wang Xiaojie , Li Yawei , Liu Yuanyuan , Zhang Dongle , Ni Min , Jia Bing , Heng Wei , Fang Zemin , Zhu Li-wu , Liu Pu 

TITLE=Transcriptomic and Proteomic Profiling Reveal the Key Role of AcMYB16 in the Response of Pseudomonas syringae pv. actinidiae in Kiwifruit

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.756330

DOI=10.3389/fpls.2021.756330

ISSN=1664-462X

ABSTRACT=<p>Kiwifruit bacterial canker caused by <italic>Pseudomonas syringae</italic> pv. <italic>actinidiae</italic> (<italic>Psa</italic>), is an important disease of kiwifruit (<italic>Actinidia</italic> Lind.). Plant hormones may induce various secondary metabolites to resist pathogens via modulation of hormone-responsive transcription factors (TFs), as reported in past studies. In this study, we showed that JA accumulated in the susceptible cultivar <italic>Actinidia chinensis</italic> ‘Hongyang’ but decreased in the resistant cultivar of <italic>A. chinensis</italic> var. <italic>deliciosa</italic> ‘Jinkui’ in response to <italic>Psa</italic>. Integrated transcriptomic and proteomic analyses were carried out using the resistant cultivar ‘Jinkui’. A total of 5,045 differentially expressed genes (DEGs) and 1,681 differentially expressed proteins (DEPs) were identified after <italic>Psa</italic> infection. Two pathways, ‘plant hormone signal transduction’ and ‘phenylpropanoid biosynthesis,’ were activated at the protein and transcript levels. In addition, a total of 27 R2R3-MYB transcription factors (TFs) were involved in the response to <italic>Psa</italic> of ‘Jinkui,’ including the R2R3-MYB TF subgroup 4 gene <italic>AcMYB16</italic>, which was downregulated in ‘Jinkui’ but upregulated in ‘Hongyang.’ The promoter region of <italic>AcMYB16</italic> has a MeJA responsiveness <italic>cis</italic>-acting regulatory element (CRE). Transient expression of the <italic>AcMYB16</italic> gene in the leaves of ‘Jinkui’ induced <italic>Psa</italic> infection. Together, these data suggest that <italic>AcMYB16</italic> acts as a repressor to regulate the response of kiwifruit to <italic>Psa</italic> infection. Our work will help to unravel the processes of kiwifruit resistance to pathogens and will facilitate the development of varieties with resistance against bacterial pathogens.</p>