Ling Chengcheng, Yang Jun, Xu Jiale, Tang Wei, Liu Yunyan, Wang Yingzhen, Li Pengwei, He Yan, Ouyang Zhiyin, Chen Shuqi, Xing Fei, Wang Xinxin, Liu Pu, Liu Yajing, Wang Runze, Liu Xiaofen, Yin Xueren, Huo Heqiang, Li Dawei, Smalle Jan, Liu Yongsheng, Wang Songhu
Anhui Province Key Laboratory of Horticultural Crop Quality Biology, School of Horticulture, Anhui Agricultural University, Hefei, China.
College of Food and Bioengineering, Bengbu University, Bengbu, China.
Nat Commun. 2025 Jul 4;16(1):6184. doi: 10.1038/s41467-025-61593-5.
The genus of Actinidia consists of the popular kiwifruits consuming worldwide. Most kiwifruit species are naturally distributed in warm and moist environments. So, they are vulnerable to high levels of heat stress. Till now, genetic basis of kiwifruit thermotolerance has remained largely unexplored. Here, we uncover a natural variation responsible for thermotolerance in kiwifruit species. We reveal that thermotolerant kiwifruit species have increased expression of AcEGY3, a gene encoding a chloroplast-localized protein, which can promote expression of nuclear thermotolerance genes via HO-dependent retrograde signaling. We show that natural variation in the promoter of AcEGY3 constitute a binding site for the heat stress-inducible transcription factor AcGATA1. The increased expression of AcEGY3 is regulated by AcGATA1 and its possible interaction with another transcription factor AcHSFA2-2. This natural variation is absent from the thermosensitive kiwifruit species. Collectively, our results reveal genetic basis of kiwifruit thermotolerance and set the foundation for breeding thermotolerant kiwifruits cultivars.
猕猴桃属包含全球广泛食用的猕猴桃。大多数猕猴桃物种自然分布于温暖湿润的环境中。因此，它们易受高水平热胁迫的影响。到目前为止，猕猴桃耐热性的遗传基础在很大程度上仍未被探索。在此，我们发现了猕猴桃物种中一个与耐热性相关的自然变异。我们揭示，耐热猕猴桃物种中编码叶绿体定位蛋白的基因AcEGY3的表达增加，该蛋白可通过HO依赖的逆行信号促进核耐热基因的表达。我们表明，AcEGY3启动子的自然变异构成了热胁迫诱导转录因子AcGATA1的一个结合位点。AcEGY3表达的增加受AcGATA1及其与另一个转录因子AcHSFA2-2可能的相互作用调控。这种自然变异在热敏猕猴桃物种中不存在。总体而言，我们的结果揭示了猕猴桃耐热性的遗传基础，并为培育耐热猕猴桃品种奠定了基础。
