Unlocking wheat fertility: map-based cloning spotlights anther-specific TaAGO5c as a master modulator

Area of Science:

• Plant reproductive biology
• Molecular genetics
• Wheat breeding

Background:

• Reproductive organ development is vital for gamete production, but its regulators in wheat are unclear.
• Sterile wheat mutants provide insights into essential genetic pathways.

Purpose of the Study:

• To identify genes regulating reproductive development in wheat.
• To elucidate the function of TaAGO5c in wheat fertility.

Main Methods:

• Cytological analysis of a sterile mutant (ste).
• Bulked segregant analysis (BSA) and map-based cloning to identify the causative gene.
• Gene editing to confirm gene function.
• Expression analysis and subcellular localization of TaAGO5c.
• Transcriptome sequencing to analyze gene expression patterns.

Main Results:

• A sterile mutant (ste) with indehiscent anthers and shrunken pollen was identified.
• TaAGO5c was identified as the gene responsible for sterility, with mutations causing tapetal degeneration and meiotic defects.
• Knockout of TaAGO5c homeologs significantly reduced fertility.
• TaAGO5c is expressed in young spikes and anthers and localized in the cytoplasm.
• Differential gene expression analysis revealed enrichment in tapetal development and meiosis pathways in the mutant.

Conclusions:

• TaAGO5c is a critical regulator of reproductive development in wheat.
• This study enhances understanding of the genetic control of tapetum and Ubisch body development, crucial for wheat fertility.