O-GlcNAc and phosphorylation modifications on HtL1/FBA10 regulate wheat vernalization for flowering

Area of Science:

• Plant Biology
• Genetics
• Agricultural Science

Background:

• Flowering time in wheat is crucial for yield and adaptation, influenced by vernalization and sugar metabolism.
• The molecular link between carbohydrate metabolism and the vernalization response in wheat remains poorly understood.
• Genetic diversity in flowering time genes is key for developing climate-resilient wheat varieties.

Purpose of the Study:

• To identify genes connecting carbohydrate metabolism with vernalization-induced flowering time regulation in wheat.
• To elucidate the mechanism by which sugar metabolism influences epigenetic modifications controlling flowering time.

Main Methods:

• Genome-wide association study (GWAS) on wheat core germplasm collections.
• Evolutionary analysis of HtL1/FBA10 haplotypes.
• Biochemical assays to assess HtL1/FBA10 phosphorylation, O-GlcNAcylation, and enzymatic activity.
• Analysis of histone acetylation at the VERNALIZATION 1 (VRN1) locus.

Main Results:

• A fructose 1,6-bisphosphate aldolase (FBA) gene, HtL1/FBA10, was identified as a key modulator of wheat heading time.
• Evolutionary analysis revealed a decrease in a late-flowering haplotype of HtL1 in modern wheat varieties.
• Vernalization alters HtL1/FBA10 post-translational modifications (phosphorylation and O-GlcNAcylation), enhancing its activity and promoting VRN1 transcription via epigenetic changes.

Conclusions:

• HtL1/FBA10 acts as a molecular bridge between glucose metabolism and the vernalization pathway in winter wheat.
• The findings reveal a novel mechanism involving sugar metabolism and epigenetic regulation of flowering time.
• This study provides insights for breeding climate-resilient wheat varieties with optimized flowering times.