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An effector of a necrotrophic fungal pathogen targets the calcium-sensing receptor in chloroplasts to inhibit host resistance.

ABSTRACT: SsITL, a secretory protein of the necrotrophic phytopathogen Sclerotinia sclerotiorum, was previously reported to suppress host immunity at the early stages of infection. However, the molecular mechanism that SsITL uses to inhibit plant defence against S. sclerotiorum has not yet been elucidated. Here, we report that SsITL interacted with a chloroplast-localized calcium-sensing receptor, CAS, in chloroplasts. We found that CAS is a positive regulator of the salicylic acid signalling pathway in plant immunity to S. sclerotiorum and CAS-mediated resistance against S. sclerotiorum depends on Ca²⁺ signalling. Furthermore, we showed that SsITL could interfere with the plant salicylic acid (SA) signalling pathway and SsITL-expressing transgenic plants were more susceptible to S. sclerotiorum. However, truncated SsITLs (SsITL-NT1 or SsITL-CT1) that lost the ability to interact with CAS do not affect plant resistance to S. sclerotiorum. Taken together, our findings reveal that SsITL inhibits SA accumulation during the early stage of infection by interacting with CAS and then facilitating the infection by S. sclerotiorum.

SUBMITTER: Tang L

PROVIDER: S-EPMC7170781 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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An effector of a necrotrophic fungal pathogen targets the calcium-sensing receptor in chloroplasts to inhibit host resistance.

Tang Liguang L Yang Guogen G Ma Ming M Liu Xiaofan X Li Bo B Xie Jiatao J Fu Yanping Y Chen Tao T Yu Yang Y Chen Weidong W Jiang Daohong D Cheng Jiasen J

Molecular plant pathology 20200227 5

SsITL, a secretory protein of the necrotrophic phytopathogen Sclerotinia sclerotiorum, was previously reported to suppress host immunity at the early stages of infection. However, the molecular mechanism that SsITL uses to inhibit plant defence against S. sclerotiorum has not yet been elucidated. Here, we report that SsITL interacted with a chloroplast-localized calcium-sensing receptor, CAS, in chloroplasts. We found that CAS is a positive regulator of the salicylic acid signalling pathway in p ...[more]

PMID: 32105402

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Dataset Information

An effector of a necrotrophic fungal pathogen targets the calcium-sensing receptor in chloroplasts to inhibit host resistance.

Publications

An effector of a necrotrophic fungal pathogen targets the calcium-sensing receptor in chloroplasts to inhibit host resistance.

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