Fig fruit ripening is regulated by the interaction between ethylene and abscisic acid

• 作者: Han Qiao Han Zhang Zhun Wang Yuanyue Shen
• 来源期刊: 植物学报（英文版）
• 年，卷（期）: 2021,（3）
• 所属期刊栏目: Research Articles
• 页码范围: 553-569
• 页数: 17页
• 语种: 英文

摘要

Fleshy fruit ripening is typically regulated by eth-ylene in climacteric fruits and abscisic acid (ABA) in non-climacteric fruits. Common fig (Ficus carica) shows a dual-ripening mechanism, which is not fully understood. Here, we detected separate peaks of ethylene and ABA in fig fruits at the onset-and on-ripening stages, in conjunction with a sharp rise in glucose and fructose contents. In a newly-designed split-fruit system, exogenous ethylene failed to rescue fluridone-inhibited fruit ripening, whereas exogenous ABA rescued 2-amino-ethoxy-vinyl gly-cine (AVG)-inhibited fruit ripening. Transcriptome analysis revealed changes in the expression of genes key to both ABA and ethylene biosynthesis and perception during fig fruit ripening. At the de-greening stage, downregulation of FcACO2 or FcPYL8 retarded ripening, but downregulation of FcETR1/2 did not;unexpectedly, downregulation of FcAAO3 promoted ripening, but it inhibited ripening only before the de-greening stage. Furthermore, we detected an increase in ethylene emissions in the FcAAO3-RNAi ripening fruit and a decrease in ABA levels in the FcACO2-RNAi unripening fruit. Im-portantly, FcPYL8 can bind to ABA, suggesting that it functions as an ABA receptor. Our findings sup-port the hypothesis that ethylene regulates the fig fruit ripening in an ABA-dependent manner. We propose a model for the role of the ABA–ethylene interaction in climacteric/non-climacteric processes.