Characterization of the core region of grape VvHOS1 promoter activity and its upstream regulatory proteins

• Published in: Environmental and experimental botany 2023-03, Vol.207, p.105199, Article 105199
• Main Authors: Wu, Nan, Li, Junduo, Zheng, Qiaoling, Wu, Jieping, Xu, Weirong
• Format: Article
• Language: English
• Subjects: Cold stresses; Promoter activity; Regulatory proteins; VvHOS1
• ISSN: 0098-8472; 1873-7307
• DOI: 10.1016/j.envexpbot.2022.105199

The tropical origins of the grape (Vitis vinifera L.) make it vulnerable to low temperatures, which constitute a serious threat to grape production. Our knowledge of the molecular basis of cold tolerance in perennial grape species is limited. The E3 ubiquitin ligase HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENE 1 (HOS1) has been demonstrated to negatively regulate cold responsiveness, but the understanding of the HOS1 in grape remains fragmentary. Here, we initially evaluated the expression of HOS1 in cold-tolerant Vitis amurensis (VaHOS1) and susceptible V. vinifera (VvHOS1) cultivars and discovered their responses to cold stress differed significantly. The two grape HOS1 genes exhibit a high degree of sequence similarity (98.77% at the amino acid level) but their lengths (313-bp insertion/deletion polymorphism) and promoter sequences are substantially different (91.96%). This 313-bp region significantly affects the differential expression of HOS1 between V. vinifera and V. amurensis. The 313-bp deletion abolished VvHOS1 promoter activity in promoter-GUS assay of transgenic Arabidopsis. Moreover, 313-bp fragment might function as a positive core region to affect promoter activity of VvHOS1 to involved in different developmental stages and cold stress. In addition, DNA pull-down and mass spectrometry (MS) assay revealed the potential regulatory proteins may bind to the 313-bp core promoter region. We show that the two linker histone H1 genes (designated as VvHH1: LOC100853898 and LOC100259836), and one sister chromatid cohesion protein PDS5 homolog B (designated as VvPDS5B: LOC100853350), which associates with the core promoter region, decreases or activates GUS expression. This work elucidates the expression features of the HOS1 promoter from genus Vitis and further identifies a core region required for the promoter activity via trans-activation or suppression of candidate regulatory proteins. •Under low temperature stress, HOS1 expression in cold-sensitive Vitis vinifera was considerably different from cold-tolerant Vitis amurensis.•The HOS1 promoter divergence between V. vinifera and V. amurensis influences the expression and function in Vitis species.•The identified 313-bp promoter of HOS1 in V. vinifera was sufficient for strong basal promoter activity.