College of Horticulture, Gansu Agricultural University, Lanzhou, China.
Physiol Plant. 2023 May-Jun;175(3):e13910. doi: 10.1111/ppl.13910.
Drought is one of the main abiotic factors affecting grape quality. However, the impacts of drought stress on sugar and related gene expression during grape berry ripening remain unclear. In this experiment, the grapes were subjected to different levels of continuous water stress from 45 to 120 days after flowering (DAA) to study the changes in berry sugar content and the expression of genes related to sugar metabolism under different water stresses. Data supported that glucose, fructose, sucrose, and soluble sugars increased from 45 DAA. Combined with previous research results, T1, T2, and Ct grape berries with 60 ~ 75 DAA and large differences in sucrose, fructose, glucose and soluble sugars compared with the Ct were selected for RNA sequencing (RNA-seq). Through transcriptome analysis, 4471 differentially expressed genes (DEGs) were screened, and 65 genes in photosynthesis, ABA signaling pathway and photosynthetic carbon metabolism pathway were analyzed further by qRT-PCR. At 60 DAA, the relative expression levels of CAB1R, PsbP, SNRK2, and PYL9 were significantly upregulated in response to water stress, while AHK1, At4g02290 were down-regulated. At 75 DAA, the relative expression levels of ELIP1, GoLS2, At4g02290, Chi5, SAPK, MAPKKK17, NHL6, KINB2, and AHK1 were upregulated. And CAB1R, PsbA, GoLS1, SnRK2, PYL9, and KINGL were significantly downregulated under moderate water stress. In addition, PsbA expression was down-regulated in response to water stress. These results will help us to fully understand the potential connections between glucose metabolism and gene expression in grapes under drought stress.
干旱是影响葡萄品质的主要非生物因素之一。然而，干旱胁迫对葡萄浆果成熟过程中糖及相关基因表达的影响尚不清楚。本试验以葡萄为试材，在盛花后 45120 d 内采用不同程度的持续水分胁迫处理，研究不同水分胁迫下浆果糖含量的变化及糖代谢相关基因的表达。结果表明，在盛花后 45 d 时，葡萄糖、果糖、蔗糖和可溶性糖的含量开始增加。结合前期研究结果，选择 T1、T2 和 Ct 葡萄浆果在 6075 DAA 时，蔗糖、果糖、葡萄糖和可溶性糖与 Ct 差异较大，用于 RNA 测序（RNA-seq）。通过转录组分析，筛选到 4471 个差异表达基因（DEGs），进一步对光合作用、ABA 信号通路和光合碳代谢途径中的 65 个基因进行 qRT-PCR 分析。在 60 DAA 时，CAB1R、PsbP、SNRK2 和 PYL9 对水分胁迫的响应显著上调，而 AHK1、At4g02290 下调。在 75 DAA 时，ELIP1、GoLS2、At4g02290、Chi5、SAPK、MAPKKK17、NHL6、KINB2 和 AHK1 的相对表达水平上调，而 CAB1R、PsbA、GoLS1、SnRK2、PYL9 和 KINGL 则在中度水分胁迫下显著下调。此外，PsbA 表达在水分胁迫下下调。这些结果将有助于我们充分了解葡萄在干旱胁迫下葡萄糖代谢与基因表达之间的潜在联系。
