DNA methylation mediates genetic variation for adaptive transgenerational plasticity

Area of Science:

• Plant biology
• Epigenetics
• Transgenerational plasticity

Background:

• Environmental stresses can induce adaptive transgenerational plasticity in offspring.
• Mechanisms of this plasticity, such as DNA methylation, are not fully understood.
• Polygonum persicaria exhibits adaptive plasticity in response to parental drought stress.

Purpose of the Study:

• To investigate the role of DNA methylation in mediating adaptive transgenerational plasticity in Polygonum persicaria.
• To determine if environmentally induced DNA methylation changes transmit parental drought stress effects to offspring.

Main Methods:

• Plants from 12 genetic lines were subjected to parental drought stress.
• Offspring were treated with a demethylating agent (zebularine) or control during germination.
• Offspring phenotypes (root length, biomass) were assessed under drought conditions.

Main Results:

• Offspring of drought-stressed parents showed enhanced root growth and biomass under drought.
• Demethylation eliminated these adaptive effects, indicating DNA methylation's role.
• Effects varied by genetic line, and seed provisioning was not a factor.

Conclusions:

• DNA methylation mediates adaptive transgenerational effects of parental drought stress in Polygonum persicaria.
• These epigenetic mechanisms are genotype-specific.
• This study provides evidence for DNA methylation as a key transgenerational plasticity mechanism.