MiR396 regulatory network and its expression during grain development in wheat.

Area of Science:

• Plant molecular biology
• Genomics
• Agricultural science

Background:

• The miR396 family is abundant in Poaceae, with wheat having the most members (17).
• The regulatory network of miR396 in wheat grain development remains largely unexplored.
• Understanding miR396's role is crucial for improving wheat yield and quality.

Purpose of the Study:

• To comprehensively explore the miR396 regulatory network in wheat grain development.
• To investigate the evolutionary conservation and diversification of the miR396 family in Poaceae, particularly in wheat.
• To identify the target genes and functional pathways regulated by miR396 during wheat grain filling.

Main Methods:

• Bioinformatic analysis of miR396 precursor sequences and haplotypes in Poaceae and wheat.
• Gene Ontology (GO) enrichment analysis of predicted miR396 target genes.
• Functional annotation of shared target genes, focusing on growth-regulating factor (GRF) genes.

Main Results:

• The miR396 family in Poaceae shows both conservation and diversification, with wheat possessing unique haplotypes (Hap-4 and Hap-5).
• miR396a and miR396n target genes exhibit distinct GO enrichment functions, differing from other miR396 members.
• miR396 regulates wheat grain development by targeting GRF genes (GRF1, GRF6, GRF9) during grain filling.

Conclusions:

• Wheat's polyploidization has enriched the diversity of the miR396 family, its target genes, and associated functional networks.
• The miR396 family plays a significant role in wheat grain development through the regulation of GRF genes.
• This study provides a foundation for further research into the function of the miR396 gene family in wheat.