Genome-wide DNA methylation dynamics and RNA-seq analysis during grape (cv. 'Cabernet Franc') skin coloration

Area of Science:

• Plant biology
• Epigenetics
• Genomics

Background:

• Grape skin coloration is a complex process influenced by various factors.
• Understanding the epigenetic mechanisms, such as DNA methylation, is crucial for grape berry development.

Purpose of the Study:

• To generate whole genome DNA methylation maps of grape skins (cv. 'Cabernet Franc').
• To characterize DNA methylomes during grape skin coloration.
• To examine the functional significance of DNA methylation in this process.

Main Methods:

• Whole genome DNA methylation mapping was performed on grape skin tissues.
• Samples were collected at three key developmental stages: early swelling, late swelling, and veraison.
• Differentially methylated regions (DMRs) were identified and analyzed.

Main Results:

• DNA methylation levels were higher in transposable element regions than genic regions.
• Within genic regions, CG and CHG methylation levels were higher than CHH.
• DMRs predominantly occurred in the CHH context during coloration, with enriched genes in nucleotide binding and flavonoid biosynthesis pathways.

Conclusions:

• DNA methylation, especially in the CHH context, plays a significant role in grape skin coloration.
• The identified DMRs and associated genes provide insights into the epigenetic regulation of flavonoid biosynthesis.
• This study lays a foundation for further research into grape berry development mechanisms.