Differential requirement of TIR enzymatic activities in TIR-type immune receptor SNC1-mediated immunity.
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ABSTRACT:
SUBMITTER: Tian L
PROVIDER: S-EPMC9706416 | biostudies-literature | 2022 Nov
REPOSITORIES: biostudies-literature
Publications
Differential requirement of TIR enzymatic activities in TIR-type immune receptor SNC1-mediated immunity.
Tian Lei L Lu Junxing J Li Xin X
Plant physiology 20221101 4
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Project description:Following the recognition of pathogen-encoded effectors, plant TIR-NB-LRR immune receptors induce defense signaling by a largely unknown mechanism. We identify a novel and conserved role for the SQUAMOSA PROMOTER BINDING PROTEIN (SBP)-domain transcription factor SPL6 in enabling the activation of the defense transcriptome following its association with a nuclear-localized immune receptor. During an active immune response, the Nicotiana TIR-NB-LRR N immune receptor associates with NbSPL6 within distinct nuclear compartments. NbSPL6 is essential for the N-mediated resistance to Tobacco mosaic virus. Similarly, the presumed Arabidopsis ortholog AtSPL6 is required for the resistance mediated by the TIR-NB-LRR RPS4 against Pseudomonas syringae carrying the avrRps4 effector. Transcriptome analysis indicates that AtSPL6 positively regulates a subset of defense genes. A pathogen-activated nuclear-localized TIR-NB-LRR like N can therefore regulate defense genes through SPL6 in a mechanism analogous to the induction of MHC genes by mammalian immune receptors like CIITA and NLRC5.
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