Discovery of Hub Genes Involved in Seed Development and Lipid Biosynthesis in Sea Buckthorn (Hippophae rhamnoides L.)...

Area of Science:

• Plant Genetics and Breeding
• Biochemistry and Molecular Biology

Background:

• Sea buckthorn is a valuable woody oil species, important for soil conservation and rich in bioactive seed oil.
• Low seed oil content and small seed size are major limitations for sea buckthorn cultivation and utilization.

Purpose of the Study:

• To identify key genes and transcription factors regulating seed development and lipid biosynthesis in sea buckthorn.
• To discover sea buckthorn cultivars with superior seed oil content and seed size for breeding programs.

Main Methods:

• Evaluated seed oil content and seed size across 12 sea buckthorn cultivars.
• Integrated Unique Identifiers RNA-sequencing (UID RNA-seq), weighted gene co-expression network analysis (WGCNA), and quantitative real-time PCR (qRT-PCR).
• Analyzed gene expression patterns during two seed developmental stages (S1 and S2).

Main Results:

• Identified five cultivars with significantly higher oil content and five with significantly heavier seeds.
• Detected 10,873 differentially expressed genes between seed developmental stages.
• Screened 417 candidate genes from five WGCNA modules linked to seed oil and size, identifying hub genes (e.g., ATP synthase subunits, Acyl carrier protein 1) and transcription factors (e.g., DOF1.2, BHLH137, ERF4) involved in seed development, lipid biosynthesis, and enlargement.

Conclusions:

• This study provides critical insights into the genetic basis of seed traits in sea buckthorn.
• Identified specific genes and transcription factors offer promising targets for marker-assisted selection and breeding to enhance sea buckthorn oil yield and quality.