Department of Horticulture, Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Yuhangtang Road 866, Hangzhou, 310058, China.
Hainan Institute, Zhejiang University, Sanya, 572000, China.
New Phytol. 2022 Nov;236(3):989-1005. doi: 10.1111/nph.18403. Epub 2022 Aug 13.
Natural variations in cis-regulatory regions often affect crop phenotypes by altering gene expression. However, the mechanism of how promoter mutations affect gene expression and crop stress tolerance is still poorly understood. In this study, by analyzing RNA-sequencing (RNA-Seq) data and reverse transcription quantitative real-time PCR validation in the cultivated tomato and its wild relatives, we reveal that the transcripts of WRKY33 are almost unchanged in cold-sensitive cultivated tomato Solanum lycopersicum L. 'Ailsa Craig' but are significantly induced in cold-tolerant wild tomato relatives Solanum habrochaites LA1777 and Solanum pennellii LA0716 under cold stress. Overexpression of SlWRKY33 or ShWRKY33 positively regulates cold tolerance in tomato. Variant of the critical W-box in SlWRKY33 promoter results in the loss of self-transcription function of SlWRKY33 under cold stress. Analysis integrating RNA-Seq and chromatin immunoprecipitation sequencing data reveals that SlWRKY33 directly targets and induces multiple kinases, transcription factors, and molecular chaperone genes, such as CDPK11, MYBS3, and BAG6, thus enhancing cold tolerance. In addition, heat- and Botrytis-induced WRKY33s expression in both wild and cultivated tomatoes are independent of the critical W-box variation. Our findings suggest nucleotide polymorphism in cis-regulatory regions is crucial for different cold sensitivity between cultivated and wild tomato plants.
顺式调控区的自然变异常常通过改变基因表达来影响作物表型。然而，启动子突变如何影响基因表达和作物的抗逆性的机制仍知之甚少。在这项研究中，通过分析栽培番茄及其野生近缘种的 RNA 测序（RNA-Seq）数据和反转录定量实时 PCR 验证，我们揭示了 WRKY33 的转录本在冷敏感栽培番茄 Solanum lycopersicum L. 'Ailsa Craig' 中几乎不变，但在冷耐受野生番茄近缘种 Solanum habrochaites LA1777 和 Solanum pennellii LA0716 中在冷胁迫下显著诱导。SlWRKY33 或 ShWRKY33 的过表达在番茄中正向调节耐冷性。SlWRKY33 启动子中关键 W-box 的变异导致 SlWRKY33 在冷胁迫下丧失自身转录功能。整合 RNA-Seq 和染色质免疫沉淀测序数据的分析表明，SlWRKY33 直接靶向并诱导多个激酶、转录因子和分子伴侣基因，如 CDPK11、MYBS3 和 BAG6，从而增强了耐冷性。此外，野生和栽培番茄中热激和 Botrytis 诱导的 WRKY33 表达不依赖于关键 W-box 的变异。我们的研究结果表明，顺式调控区的核苷酸多态性对于栽培和野生番茄植物之间的不同冷敏感性至关重要。
