METTL4 interacts with histone methylation readers MRG1/2 to regulate alternative splicing and promote thermomorphogenesis in Arabidopsis.

METTL4 and MRG1/2 co-regulate alternative splicing and promote thermomorphogenesis in Arabidopsis, with mutants showing reduced hypocotyl elongation at 28°C.

• Why it matters: Understanding how alternative splicing is regulated during thermomorphogenesis is crucial because it influences plant adaptation to temperature changes, yet the mechanisms remain unclear.
• What they did: The study used Arabidopsis mutants and transcriptome analysis to show that METTL4 interacts with MRG1/2, affecting gene transcription and alternative splicing of brassinosteroid signaling genes under warm conditions.
• The result: Findings suggest METTL4 and MRG1/2 jointly modulate alternative splicing and brassinosteroid signaling to enhance thermomorphogenesis, independent of METTL4’s methyltransferase activity.