Sorbitol Reduces Sensitivity to Alternaria by Promoting Ceramide Kinases (CERK) Expression through Transcription Factor Pswrky25 in Populus (Populus simonii Carr.)

Abstract

Sugar, acting as a signal, can regulate the production of some chemical substance during plant defense responses. However, the molecular basis and regulatory mechanisms of sugar in poplar and other forest trees are still unclear. Sorbitol is a sugar-signaling molecule associated with plant defense. In this study, the pathogen-infested status of poplar was alleviated after exogenous feeding of 50 mM sorbitol. We sequenced and analyzed the transcriptome of poplar leaves before and after inoculation. The results showed that the genes PR1, WRKY, ceramide kinases (CERK) and so on responded to sorbitol feeding and pathogen infestation. We screened for genes related to disease resistance such as PsWRKY25 and PsCERK1 and found that significant disease spots occurred on day six of strep throat infestation. Under sorbitol feeding conditions, the appearance of spots was delayed after the pathogen inoculation. Due to the overexpression of PsWRKY25, the overexpression of PsCERK1 triggered the defense response in poplar. This was also confirmed by PsWRKY25 overexpression experiments. These findings present new insights into the influence of sorbitol on Populus simonii Carr. disease resistance. These results emphasize the value of molecular phenotypes in predicting physiological changes.

Genome-wide analysis of TPX2 gene family in Populus trichocarpa and its specific response genes under various abiotic stresses

“…The quality of RNA samples were determined by the NanoDrop 8000 (Thermo Fisher Scientific, Waltham, Massachusetts, USA) ( Desjardins and Conklin, 2010 ; Lei et al., 2019 ). Then, using 1 µg RNA as the template, the RNA was reverse transcribed into cDNA using the rapid quantitative RT Supermix Kit (M-MLV Reverse Transcriptase, Mi Si Century Biotechnology company, Shanghai, China) ( Qi et al., 2022 ). The cDNA was stored at - 20 °C for subsequent RT-qPCR experiments.…”

Comprehensive Overview of <i>Populus</i> <i>simonii</i> Research in the Recent Years

“…Further studies have shown that PsnWRKY70 enhances poplar resistance to Rhizoctonia allochthonii by activating genes related to pathogen-related molecular patterns (PTI) and effector-induced immunity (ETI) [40]. Exogenous application of sorbitol can further induce PsWRKY25 and PsCERK1 to improve the resistance of P. simonii to diseases [41]. These findings demonstrate the complex disease resistance mechanism of P. In addition to the above, Yuting Wang [42] also characterized 9 PtSROs in Populus plants that can respond to different kinds of abiotic stress.…”

Editing Metabolism, Sex, and Microbiome: How Can We Help Poplar Resist Pathogens?

“…It was found that sorbitol exposure increased poplar resistance to A. alternata, and PsWRKY25 was one of the most important effectors: it activated the expression of PsCERK1 (ceramide kinase 1) gene, MAPK cascade genes and secondary metabolites, including phenylpropanoids, biosynthetic genes, etc. Poplar overexpressing PsWRKY25 also had increased resistance to this pathogen [198].…”