Chen Haiyang, Liu Xinna, Li Shenchang, Yuan Ling, Mu Huayuan, Wang Yi, Li Yang, Duan Wei, Fan Peige, Liang Zhenchang, Wang Lijun
Beijing Key Laboratory of Grape Science and Enology and Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
China National Botanical Garden, Beijing 100093, China.
Hortic Res. 2023 Jan 4;10(3):uhad001. doi: 10.1093/hr/uhad001. eCollection 2023 Mar.
Grape is a widely cultivated crop with high economic value. Most cultivars derived from mild or cooler climates may not withstand increasing heat stress. Therefore, dissecting the mechanisms of heat tolerance in grapes is of particular significance. Here, we performed comparative transcriptome analysis of 'Tangwei' (heat tolerant) and 'Jingxiu' (heat sensitive) grapevines after exposure to 25°C, 40°C, or 45°C for 2 h. More differentially expressed genes (DEGs) were detected in 'Tangwei' than in 'Jingxiu' in response to heat stress, and the number of DEGs increased with increasing treatment temperatures. We identified a class B Heat Shock Factor, HSFB1, which was significantly upregulated in 'Tangwei', but not in 'Jingxiu', at high temperature. VdHSFB1 from 'Tangwei' and VvHSFB1 from 'Jingxiu' differ in only one amino acid, and both showed similar transcriptional repression activities. Overexpression and RNA interference of in grape indicated that HSFB1 positively regulates the heat tolerance. Moreover, the heat tolerance of -overexpressing plants was positively correlated to expression level. The activity of the promoter is higher than that of under both normal and high temperatures. Promoter analysis showed that more TATA-box and AT~TATA-box -elements are present in the promoter than the promoter. The promoter sequence variations between and likely determine the expression levels that influence heat tolerance of the two grape germplasms with contrasting thermotolerance. Collectively, we validated the role of in heat tolerance, and the knowledge gained will advance our ability to breed heat-tolerant grape cultivars.
葡萄是一种广泛种植且具有高经济价值的作物。大多数源自温和或凉爽气候的品种可能无法承受不断增加的热胁迫。因此，剖析葡萄耐热机制具有特别重要的意义。在此，我们对‘唐威’（耐热）和‘京秀’（热敏）葡萄在25°C、40°C或45°C处理2小时后进行了比较转录组分析。响应热胁迫，在‘唐威’中检测到的差异表达基因（DEG）比‘京秀’中更多，并且DEG的数量随着处理温度的升高而增加。我们鉴定出一个B类热休克因子HSFB1，在高温下它在‘唐威’中显著上调，但在‘京秀’中没有。来自‘唐威’的VdHSFB1和来自‘京秀’的VvHSFB1仅在一个氨基酸上不同，并且两者都表现出相似的转录抑制活性。在葡萄中对其进行过表达和RNA干扰表明HSFB1正向调节耐热性。此外，过表达植株的耐热性与表达水平呈正相关。在正常和高温条件下，的启动子活性均高于的启动子活性。启动子分析表明，启动子中存在的TATA盒和AT~TATA盒元件比启动子更多。和之间的启动子序列变异可能决定了影响两种耐热性相反的葡萄种质耐热性的表达水平。总体而言，我们验证了在耐热性中的作用，所获得的知识将提升我们培育耐热葡萄品种的能力。
