Transcriptomic Reprogramming in Leaves During Floral Bud Morphogenesis in Blueberry

Area of Science:

• Plant Biology
• Molecular Genetics
• Developmental Biology

Background:

• Floral bud morphogenesis in blueberry is vital for yield but poorly understood at the molecular level in leaves.
• Leaf gene expression dynamics during this critical phase remain largely unelucidated.

Purpose of the Study:

• To investigate leaf gene expression patterns during floral bud morphogenesis in rabbiteye blueberry using a time-series transcriptomic approach.
• To identify key regulatory genes and pathways involved in floral bud development in blueberry leaves.

Main Methods:

• Employed time-series RNA-sequencing (RNA-seq) on blueberry leaves sampled across six developmental time points.
• Utilized weighted gene co-expression network analysis (WGCNA) to identify stage-specific gene modules and hub genes.

Main Results:

• Identified four stage-specific gene modules associated with distinct morphogenetic phases, enriched in photosynthesis, hormone signaling, and metabolism.
• Observed dynamic expression of flowering-related genes (FT, AP2, COL9) and extensive involvement of brassinosteroid signaling.
• Discovered hub genes (FT, COL9, AP2, ERF1, SR160, LOX3-1, MYB-related) as potential central regulators of floral bud development.

Conclusions:

• Blueberry leaves transition from photosynthetic organs to signaling hubs supporting reproductive development.
• This functional shift involves complex gene regulatory networks and hormone signaling pathways.
• Findings offer insights into flowering regulation in woody plants and support marker-assisted breeding and crop management.