The m⁶A reader SlYTH2 negatively regulates tomato fruit aroma by impeding the translation process

Area of Science:

• Plant molecular biology
• Epigenetics
• Fruit quality research

Background:

• N6-methyladenosine (m6A) is a key RNA modification regulating gene expression via m6A readers.
• The role of m6A readers in fruit ripening and quality is largely unknown.

Purpose of the Study:

• To investigate the function of the tomato m6A reader SlYTH2 in fruit ripening and aroma formation.
• To elucidate the molecular mechanisms by which SlYTH2 impacts fruit quality.

Main Methods:

• Transcriptome-wide m6A binding site profiling of SlYTH2.
• Analysis of SlYTH2-mediated liquid-liquid phase separation and RNA-protein condensate formation.
• Polysome profiling and proteomic analysis to assess translation efficiency.
• CRISPR-editing to generate SlYTH2 knockout tomatoes.

Main Results:

• SlYTH2 binds to m6A-modified mRNAs (SlHPL, SlCCD1B) involved in volatile synthesis, enriching them in condensates.
• Loss of SlYTH2 accelerates SlHPL and SlCCD1B translation, increasing aroma volatile production.
• CRISPR-edited tomatoes with enhanced aroma showed increased consumer preference.

Conclusions:

• SlYTH2 acts as a crucial regulator of RNA metabolism during tomato fruit ripening.
• m6A-mediated regulation by SlYTH2 influences fruit aroma and consumer appeal.
• Targeting m6A pathways offers a strategy for improving fruit quality.