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The Sex Determination Cascade in the Silkworm
Xu Yang1,2, Kai Chen1,2, Yaohui Wang1
1Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.
Genes
|March 6, 2021
Summary
In Lepidoptera (moths and butterflies), sex determination involves unique regulators like Fem and Masc, bypassing transformer (tra). The doublesex (dsx) gene
Area of Science:
- Entomology
- Developmental Biology
- Genetics
Background:
- Insect sex determination involves primary signals, transducers, and executors.
- The doublesex (dsx) gene is a conserved executor across insect orders.
- Lepidoptera exhibit unique sex determination mechanisms, lacking the transformer (tra) gene found in other insects.
Purpose of the Study:
- To review recent findings on feminization and masculinization genes in Lepidoptera.
- To elucidate the molecular mechanisms of sex determination in Lepidoptera.
- To identify future research directions for silkworm sex determination.
Main Methods:
- Literature review of genetic and molecular studies on Lepidopteran sex determination.
- Analysis of gene functions and regulatory pathways.
- Comparative genomics and molecular mechanism investigation.
Main Results:
- Lepidoptera utilize a distinct primary signal pathway involving Fem and Masc.
- The transformer (tra) gene is absent in Lepidoptera.
- A PSI protein in Bombyx mori directly regulates dsx splicing, acting as a transducer.
Conclusions:
- Lepidopteran sex determination is orchestrated by unique genetic components.
- Understanding these pathways is crucial for insect developmental biology.
- Further research is needed to fully map the regulatory networks in Lepidoptera.
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