Natural Variation in the AAT1 Promoter Is Responsible for the Disparity in Ester Aroma Between Actinidia chinensis and Actinidia eriantha
Year: 2024
Type: article
Abstract: To understand ester compound biosynthesis in kiwifruit, two Actinidia species with distinct characteristics were compared. The firmness of Donghong (Actinidia chinensis) and Ganlv-1 (Actinidia eriantha) fruits gradually decreased as the fruit ripened after harvest, whereas the total soluble solids increased continuously, reaching a peak on the 8th day. The Ganlv-1 fruit ester content was significantly lower than in the Donghong fruits at the optimal eating stage, and the alcohol acyltransferase (AAT) activity in the Ganlv-1 fruits was significantly lower than in the Donghong fruits. The gene expression levels of AAT1 and AAT17 in the Donghong fruits were significantly higher than in the Ganlv-1 fruits, with a particularly remarkable difference observed for AAT1, which exhibited a 36-fold higher expression in the Donghong fruits when compared with the fully ripened Ganlv-1 fruits. A transient overexpression of the AAT1 gene in the kiwifruit led to a significant increase in ester content. Interestingly, a natural variation was observed in the promoter sequence of AAT1 between the Donghong and Ganlv-1 cultivars. Furthermore, separate analyses of the respective promoter activities revealed significantly higher activity levels in the Donghong fruits than in the Ganlv-1 fruits. In conclusion, a natural variation in the AAT1 promoter is primarily responsible for the disparity in AAT1 gene expression between the Donghong and Ganlv-1 fruits, resulting in a divergent accumulation of ester aroma compounds during the postharvest ripening stages.
Source: Agronomy
Authors: Qing Cao, Zhenyu Huang, Jinyin Chen, Zengyu Gan
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: gold
Estimated APC paid: $2,955
OpenAlex ID: W4405315169