Abscisic Acid and Sucrose Regulate Fruit Ripening through the ASR Transcription Factor

The role of abscisic acid (ABA) and sucrose in fruit ripening is widely known. However, the mechanism of the ABA and sucrose signaling pathways remain poorly understood. A research team from Nanjing Agricultural University, headed by Haifeng Jia, studied the transcription factor ABA-stress-ripening (ASR), which is involved in ABA and sucrose signalling pathways, in strawberry and tomato.

The team identified four ASR isoforms in tomato and one in strawberry. All ASRs contained the ABA stress- and ripening-induced proteins and water-deficit stress-induced proteins and all ASRs showed increased expression during fruit development. The expression of the ASR gene was found to be influenced by sucrose, ABA, jasmonic acid and indole-3-acetic acid.

When overexpressed, the ASR gene promoted fruit softening and ripening, while RNA interference delayed fruit ripening and affected fruit physiology. This may be due to the change in ASR gene expression affecting the expression of several ripening-related genes.

The study could provide evidence on the role of ASR in the signaling between ABA and sucrose to regulate tomato and strawberry fruit ripening.

To learn more on the study, read the article in Plant Biotechnology Journal.