The 14-3-3 protein CaTFT7 interacts with transcription factor CaHDZ27 to positively regulate pepper immunity against Ralstonia solanacearum

Abstract

Bacterial wilt, caused by Ralstonia solanacearum, is a devastating disease affecting plants in the Solanaceae family. In our previous study, CaHDZ27 was shown to act crucially in the pepper defense response to R. solanacearum. However, the molecular basis underlying CaHDZ27 function remains unexplored. In this study, we demonstrate that CaHDZ27 is post-translationally regulated by the 14-3-3 protein CaTFT7, which functions as a positive regulator in pepper immunity against R. solanacearum. RT-qPCR analysis revealed that CaTFT7 is transcriptionally induced by R. solanacearum infection. The data from virus-induced gene silencing revealed that CaTFT7 positively affects pepper immunity, which was further confirmed by the data of CaTFT7-overexpressing Nicotiana benthamiana. CaTFT7 interacted with CaHDZ27, thereby promoting the stability of CaHDZ27 and enhancing CaHDZ27 binding to the promoter of cysteine-rich receptor-like protein kinase 5 (CaCRK5), a gene that positively affects pepper defense against R. solanacearum. The above data indicated that CaTFT7 enhanced CaHDZ27 stability and promoted its ability to activate pepper immunity, shedding light on the mechanisms underlying pepper resistance to bacterial wilt.

Acknowledgements

We would like to thank Dr. S. P. Dinesh-Kumar for providing vectors in VIGS assay. This work was supported by the National Natural Science Foundation of China (31301254), the Natural Science Foundation of Fujian Province (2023 J01277), and the Development Fund Project of Fujian Agriculture and Forestry University (KFB23083).

Author contributions

S.H. designed the research. S.M., X.C., and T.Z. performed the experiments. S.M., J.C., T.Z., and T.L. analyzed the data. S.M. and S.H. wrote the manuscript. All the authors read and approved the final manuscript.

Data availability

The data that support the findings of this study are available in the manuscript and its online supplementary materials.

Conflict of interest statement

The authors have no conflicts of interest to declare.

Supplementary Data

Supplementary data is available at Horticulture Research online.

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