DNA Hypomethylation Activates the RpMYB2-Centred Gene Network to Enhance Regeneration of Adventitious Roots

Area of Science:

• Plant Biology
• Epigenetics
• Molecular Genetics

Background:

• Plants require efficient regeneration to survive environmental damage.
• Adventitious roots (ARs) are crucial for nutrient uptake in detached plant tissues.
• DNA methylation is an epigenetic mechanism that regulates gene expression and has been implicated in plant regeneration.

Purpose of the Study:

• To investigate the role of DNA methylation in adventitious root (AR) regeneration in Robinia pseudoacacia (black locust).
• To identify the molecular mechanisms underlying enhanced AR regeneration induced by DNA methylation inhibition.

Main Methods:

• Application of 5-azacytidine (5-azaC), a DNA methylation inhibitor.
• Whole-genome bisulfite sequencing (WGBS) to analyze global methylation patterns.
• Yeast two-hybrid (Y2H) and yeast one-hybrid (Y1H) assays to identify protein and DNA interactions.
• Luciferase reporting assay (LRA) to validate gene promoter binding.

Main Results:

• 5-azaC treatment accelerated AR initiation and increased regeneration rates in black locust.
• WGBS revealed global hypomethylation and altered transcriptional profiles in 5-azaC-treated samples.
• A RpMYB2-centered transcription factor network, including RpWRKY23 and RpGATA23, was identified and shown to interact with target gene promoters (RpSK6, RpCDC48).

Conclusions:

• Hypomethylation-induced transcriptomic changes activate the RpMYB2 gene network, enhancing AR regeneration in black locust.
• Epigenetic modification offers a promising strategy for improving plant regeneration capabilities.
• Findings support potential applications in genetic modification for enhanced wood production and environmental resilience in plants.