A Hierarchical VvbHLH30-VvERF70-VvACS2 Module Orchestrates Ethylene Biosynthesis and Cold Adaptation in Grapevine.

Area of Science:

• Plant Biology
• Molecular Genetics
• Agricultural Science

Background:

• Ethylene is a vital phytohormone regulating plant growth and stress responses.
• Mechanisms of ethylene biosynthesis and regulation in plant cold adaptation are not fully understood.

Purpose of the Study:

• To elucidate the ethylene-associated regulatory network controlling cold adaptation in grapevines.
• To identify key genes and transcription factors involved in grapevine's response to cold stress.

Main Methods:

• Genome-wide analysis of ACS gene family in Vitis vinifera.
• CRISPR-Cas9 gene editing and overexpression for functional validation of VvACS2, VvERF70, and VvbHLH30.
• Analysis of gene expression and protein interactions under cold stress.

Main Results:

• VvACS2 identified as a major contributor to cold-induced ethylene biosynthesis in grapevine roots.
• VvERF70 and VvbHLH30 identified as transcription factors directly regulating VvACS2 expression.
• The VvbHLH30-VvERF70 complex enhances VvACS2 induction, promoting ethylene production and cold tolerance.

Conclusions:

• A hierarchical transcriptional regulatory network involving VvbHLH30, VvERF70, and VvACS2 is crucial for grapevine cold tolerance.
• This module plays a pivotal role in ethylene biosynthesis under cold stress.
• Findings provide insights into plant cold adaptation and potential strategies for frost damage mitigation in crops.