Inheritance of acquired adaptive cold tolerance in rice through DNA methylation

Area of Science:

• Plant Biology
• Epigenetics
• Genetics

Background:

• Epigenetic mechanisms may explain inheritance of acquired traits, but adaptive hereditary epigenetic alterations are rare.
• Asian rice (Oryza sativa L.) originated in tropical regions, facing challenges with northward expansion due to cold sensitivity.

Purpose of the Study:

• To investigate epigenetic pathways for acquired and heritable traits in rice.
• To identify the molecular basis of acquired cold tolerance in rice.

Main Methods:

• Multigenerational cold stress applied to cold-sensitive rice.
• Analysis of DNA methylation variations in the acquired cold tolerance 1 (ACT1) gene promoter.
• DNA methylation editing to confirm gene function.

Main Results:

• A rice line with stable, inherited cold tolerance was developed after multigenerational cold stress.
• DNA hypomethylation in the ACT1 promoter region was identified as the cause of acquired cold tolerance.
• Natural variation in ACT1 hypomethylation correlates with cold tolerance and rice distribution.

Conclusions:

• Epigenetic variation in ACT1 drives adaptive cold tolerance in rice.
• This study provides evidence for epigenetic-variation-driven inheritance of acquired characteristics.
• Identified mechanism explains rice adaptation to colder climates through heritable epigenetic changes.