Transposable-element associated small RNAs in Bombyx mori genome

Area of Science:

• Genomics
• Molecular Biology
• RNA Biology

Background:

• Eukaryotic gene expression is regulated by small RNAs.
• The silkworm (Bombyx mori) genome contains abundant repetitive sequences from transposable elements (TEs).
• TEs provide a rich source for small RNA biogenesis.

Purpose of the Study:

• To systematically discover TE-associated small RNAs in the Bombyx mori genome.
• To analyze the diversity and functional significance of these small RNAs.
• To investigate the contribution of specific TEs to small RNA generation.

Main Methods:

• Deep RNA sequencing of Bombyx mori.
• Bioinformatic analysis to identify TE-associated small RNAs.
• Comparative analysis of small RNA species and TE families.

Main Results:

• Discovery of 182,788 miRNA, 4,990 siRNA, and 788 piRNA species associated with TEs.
• Identification of preferential association between small RNA species and different TEs.
• Significant contribution of the Bombyx non-LTR retrotransposon, bm1645, to TE-associated small RNA production.
• Evidence of overlapping bm1645-associated small RNAs, suggesting diverse generation mechanisms.

Conclusions:

• Expanded understanding of the small RNA repertoire in the Bombyx mori genome.
• New insights into the diversity and functional roles of TE-associated small RNAs.
• Highlighting the significant role of specific TEs, like bm1645, in small RNA biogenesis and regulation.