Flg22‐induced Ca²⁺ increases undergo desensitization and resensitization

Journal Article · 18 September 2021 · Plant, Cell and Environment

DOI: https://doi.org/10.1111/pce.14186 · OSTI ID:1980641

Chi, Yuan  ^[1]; Wang, Chao ^[2]; Wang, Mengyun ^[3]; Wan, Di ^[2]; Huang, Feifei ^[4]; Jiang, Zhonghao ^[4]; Crawford, Bridget M. ^[5]; Vo‐Dinh, Tuan ^[5]; Yuan, Fang ^[6]; Wu, Feihua ^[7]; Pei, Zhen‐Ming  ^[5]

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1. Zhejiang University, Hangzhou (China); Duke University, Durham, NC (United States); Hangzhou Normal University Hangzhou (China); Shenzhen University, Shenzhen (China); OSTI
2. Hangzhou Normal University Hangzhou (China)
3. Zhejiang University, Hangzhou (China); Hangzhou Normal University Hangzhou (China)
4. Duke University, Durham, NC (United States); Shenzhen University, Shenzhen (China)
5. Duke University, Durham, NC (United States)
6. Duke University, Durham, NC (United States); Hangzhou Normal University Hangzhou (China)
7. Duke University, Durham, NC (United States); Hangzhou Normal University Hangzhou (China); Shenzhen University, Shenzhen (China)

The flagellin epitope flg22, a pathogen-associated molecular pattern (PAMP), binds to the receptor-like kinase FLAGELLIN SENSING2 (FLS2), and triggers Ca²⁺ influx across the plasma membrane (PM). The flg22-induced increases in cytosolic Ca²⁺ concentration ([Ca²⁺]i) (FICA) play a crucial role in plant innate immunity. It's well established that the receptor FLS2 and reactive oxygen species (ROS) burst undergo sensitivity adaptation after flg22 stimulation, referred to as desensitization and resensitization, to prevent over responses to pathogens. However, whether FICA also mount adaptation mechanisms to ensure appropriate and efficient responses against pathogens remains poorly understood. Here, we analysed systematically [Ca²⁺]i increases upon two successive flg22 treatments, recorded and characterized rapid desensitization but slow resensitization of FICA in Arabidopsis thaliana. Pharmacological analyses showed that the rapid desensitization might be synergistically regulated by ligand-induced FLS2 endocytosis as well as the PM depolarization. The resensitization of FICA might require de novo FLS2 protein synthesis. FICA resensitization appeared significantly slower than FLS2 protein recovery, suggesting additional regulatory mechanisms of other components, such as flg22-related Ca²⁺ permeable channels. Taken together, we have carefully defined the FICA sensitivity adaptation, which will facilitate further molecular and genetic dissection of the Ca²⁺-mediated adaptive mechanisms in PAMP-triggered immunity.

• Research Organization: Duke University, Durham, NC (United States)
• Sponsoring Organization: USDOE Office of Science (SC); China Scholarship Council; National Science Foundation (NSF); Chinese National Science Foundation
• Grant/Contract Number: SC0014077
• OSTI ID: 1980641
• Journal Information: Plant, Cell and Environment, Journal Name: Plant, Cell and Environment Journal Issue: 12 Vol. 44; ISSN 0140-7791
• Publisher: WileyCopyright Statement
• Country of Publication: United States
• Language: English