Histone H3K4 Methylation Mediates Exogenous Arginine Suppression of Cold-Induced Damage in Tea Plant.

Exogenous arginine enhances cold tolerance in tea plants by increasing cuticle thickness through a CsSDG36-H3K4me3-CsKCS3 regulatory module.

• Why it matters: Cold stress limits tea plant distribution and productivity, and understanding epigenetic regulation of wax biosynthesis could enable development of more resilient crops.
• What they did: Researchers used transcriptome analysis, gene silencing, and heterologous overexpression to identify that arginine increases H3K4me3 levels, activating CsKCS3 and CsSDG36, which promote fatty acid biosynthesis and wax accumulation.
• The result: Arginine treatment mitigated cold damage in CsSDG36-silenced plants by restoring CsKCS3 expression, revealing an epigenetic mechanism that fortifies the epidermal lipid barrier and improves cold tolerance.