Dynamic transcriptome analysis of Bombyx mori embryonic development.

Area of Science:

• Developmental Biology
• Genomics
• Molecular Biology

Background:

• The gene expression control governing Bombyx mori embryonic development remains largely uncharacterized despite extensive research on the organism.
• Understanding these regulatory mechanisms is crucial for advancing insect developmental biology.

Purpose of the Study:

• To comprehensively profile the transcriptome of Bombyx mori during six distinct embryonic developmental stages.
• To identify stage-specific gene expression patterns and regulatory pathways involved in embryonic development.

Main Methods:

• RNA sequencing (RNA-seq) was employed to analyze gene expression across six embryonic stages: fertilized egg, blastoderm, germ-band, organogenesis, reversal period, and youth period.
• Weighted gene correlation network analysis and differential gene expression analysis were performed.
• Quantitative real-time polymerase chain reaction, dot blot, and western blot were used for validation.

Main Results:

• A total of 12,894 transcripts were identified, with 12,456 shared across all stages.
• Early embryos exhibited upregulated genes involved in DNA replication, transcription, protein synthesis, and epigenetic modifications.
• Late embryos showed increased abundance of cuticle proteins, chitin synthesis-related proteins, and neuropeptides.
• Hormonal pathways (juvenile hormone, 20-hydroxyecdysone) and transcription factors were present throughout, with heightened activity around organogenesis.

Conclusions:

• This study elucidates critical molecular mechanisms underlying Bombyx mori embryonic development.
• The findings provide valuable insights into the dynamic regulation of gene expression during insect embryogenesis.
• Validation experiments confirmed the RNA-seq results and epigenetic modifications.