Modular cis-regulatory logic of yellow gene expression in silkmoth larvae

Area of Science:

• Developmental biology
• Genetics
• Evolutionary biology

Background:

• Pigmentation patterns in Lepidoptera are vital for adaptation.
• Genes like yellow and ebony are known to control pigmentation, but their regulation in Lepidoptera is unclear.
• Cis-regulatory modularity has been observed in dipteran pigmentation gene regulation.

Purpose of the Study:

• To investigate the cis-regulatory mechanisms controlling the tissue-specific expression of the yellow gene in Bombyx mori.
• To identify regulatory elements responsible for pigmentation in different larval regions.
• To compare the trans-regulatory landscapes of the yellow gene between Lepidoptera and Diptera.

Main Methods:

• Utilized transgenic techniques in Bombyx mori.
• Identified body parts regulated by the yellow gene for black pigmentation.
• Isolated three distinct cis-regulatory elements driving tissue-specific expression.
• Performed cross-species comparisons of cis-regulatory regions with Drosophila melanogaster.

Main Results:

• Demonstrated cis-regulatory modularity controls tissue-specific expression of the yellow gene in B. mori.
• Identified three regulatory elements controlling expression in specific larval regions.
• Found no sequence conservation in cis-regulatory regions between B. mori and D. melanogaster.
• Observed no cross-species expression when regulatory regions were introduced into the other species.

Conclusions:

• Lepidopteran species utilize cis-regulatory modules for pigmentation gene expression.
• Significant differences exist in the trans-regulatory landscapes of the yellow gene between Lepidoptera and Diptera.
• Transgenic tools in B. mori are valuable for studying evolutionary developmental mechanisms of pigmentation.