Transcriptomic and Metabolic Insight Into Flavonoid Biosynthesis Underlying Black and Yellow Seed Coat Color...

Area of Science:

• Plant Biology
• Molecular Genetics
• Biochemistry

Background:

• Soybean seed coat color variation is a key agronomic trait.
• The molecular basis of flavonoid pigment accumulation in soybean seed coats is not fully understood.

Purpose of the Study:

• To investigate the genetic and metabolic regulation of black and yellow soybean seed coat coloration.
• To identify candidate genes involved in pigment biosynthesis and transport.

Main Methods:

• Integrated RNA sequencing (RNA-Seq) and high-performance liquid chromatography (HPLC) metabolite profiling.
• Comparative analysis of gene expression and metabolite content between black and yellow soybean seed coats.

Main Results:

• Black seed coats showed higher total phenolic, flavonoid, anthocyanin, and proanthocyanidin content, along with greater antioxidant activity.
• Yellow seed coats exhibited elevated total isoflavone content.
• Differential gene expression revealed upregulation of anthocyanin biosynthesis genes (F3H, ANS) and regulatory genes (R2R3-MYB, sHSPs) in black seed coats.
• Leucoanthocyanidin reductase (LAR) and Cytochrome P450 genes were preferentially expressed in yellow seed coats.

Conclusions:

• Distinct metabolic profiles correlate with differential gene expression in soybean seed coat pigmentation.
• Identified candidate genes provide insights into the genetic control of soybean seed color and potential targets for breeding.