CsIVP functions in vasculature development and downy mildew resistance in cucumber

• Published in: PLoS biology Vol. 18; no. 3; p. e3000671
• Main Authors: Yan, Shuangshuang, Ning, Kang, Wang, Zhongyi, Liu, Xiaofeng, Zhong, Yanting, Ding, Lian, Zi, Hailing, Cheng, Zhihua, Li, Xuexian, Shan, Hongyan, Lv, Qingyang, Luo, Laixin, Liu, Renyi, Yan, Liying, Zhou, Zhaoyang, Lucas, William John, Zhang, Xiaolan
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 23.03.2020; Public Library of Science (PLoS)
• Subjects: Agriculture; Airborne microorganisms; Biology; Biology and Life Sciences; Crop diseases; Crop yield; Crops; Disease resistance; Domestication; Downy mildew; Engineering and Technology; Flowers & plants; Funding; Gene expression; Helix-loop-helix proteins; Helix-loop-helix proteins (basic); Horticulture; International cooperation; Laboratories; Morphogenesis; Morphology; Pathogenesis; Pathogens; Phenotypes; Phylogenetics; Plant diseases; Plant pathology; Plant sciences; Plant tissues; Regulators; RNA-mediated interference; Salicylic acid; Signal transduction; Transcription factors; Vascular tissue; Beijing China; California; United States > US; China
• ISSN: 1545-7885; 1544-9173; 1545-7885
• DOI: 10.1371/journal.pbio.3000671

Domesticated crops with high yield and quality are frequently susceptible to pathogen attack, whereas enhancement of disease resistance generally compromises crop yield. The underlying mechanisms of how plant development and disease resistance are coordinately programed remain elusive. Here, we showed that the basic Helix-Loop-Helix (bHLH) transcription factor Cucumis sativus Irregular Vasculature Patterning (CsIVP) was highly expressed in cucumber vascular tissues. Knockdown of CsIVP caused severe vasculature disorganization and abnormal organ morphogenesis. CsIVP directly binds to vascular-related regulators YABBY5 (CsYAB5), BREVIPEDICELLUS (CsBP), and AUXIN/INDOLEACETIC ACIDS4 (CsAUX4) and promotes their expression. Knockdown of CsYAB5 resulted in similar phenotypes as CsIVP-RNA interference (RNAi) plants, including disturbed vascular configuration and abnormal organ morphology. Meanwhile, CsIVP-RNAi plants were more resistant to downy mildew and accumulated more salicylic acid (SA). CsIVP physically interacts with NIM1-INTERACTING1 (CsNIMIN1), a negative regulator in the SA signaling pathway. Thus, CsIVP is a novel vasculature regulator functioning in CsYAB5-mediated organ morphogenesis and SA-mediated downy mildew resistance in cucumber.