Age-associated DNA methylation changes in Xenopus frogs

Area of Science:

• Comparative genomics
• Epigenetics
• Amphibian biology

Background:

• Age-associated DNA methylation changes are documented in various animals but not amphibians.
• Amphibians, including Xenopus, are important model organisms for biological research.

Purpose of the Study:

• To investigate age-associated DNA methylation patterns in the amphibian Xenopus tropicalis.
• To determine if DNA methylation changes with age in Xenopus are conserved across species.
• To establish a foundation for an epigenetic clock assay in amphibians.

Main Methods:

• Whole-genome bisulfite sequencing (WGBS) was performed on skin samples from young, mature, and old Xenopus tropicalis frogs.
• Gene- and chromosome-scale DNA methylation changes were analyzed.
• Targeted DNA methylation analysis (TBSseq) was developed and piloted.

Main Results:

• Clear evidence of age-associated DNA methylation changes was found in Xenopus tropicalis.
• Observed methylation patterns showed consistency with those in mammalian species, suggesting conserved aging mechanisms.
• A pilot TBSseq experiment successfully recapitulated WGBS findings, supporting its utility.

Conclusions:

• Xenopus tropicalis exhibits conserved age-associated DNA methylation patterns, similar to mammals.
• The developed TBSseq assay provides a basis for future epigenetic clock development in amphibians.
• This research enables leveraging Xenopus resources to study DNA methylation in aging.