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Larval RNA Interference in Silkworm Bombyx mori through Chitosan/dsRNA Nanoparticle Delivery
Published on: October 4, 2024
The genetic system controlling recombination in the silkworm.
1Laboratory of Sericultural Science, Faculty of Agriculture, University of Tokyo, Bunkyo-ku, Tokyo, 113 Japan.
Genetics
|October 1, 1981
Summary
Recombination modifiers in Bombyx mori influence recombination rates between specific loci on chromosome 2, acting as polygenic factors rather than chromosomal aberrations, particularly in low recombination lines.
Area of Science:
- Genetics
- Molecular Biology
- Evolutionary Biology
Background:
- Recombination frequency is a critical factor in genetic diversity and evolution.
- Understanding the genetic basis of recombination rate variation is essential for genetic studies.
- Bombyx mori serves as a model organism for studying insect genetics and development.
Purpose of the Study:
- To investigate the nature of recombination modifiers in Bombyx mori.
- To determine the genetic basis of high and low recombination rates between specific loci.
- To differentiate between chromosomal aberrations and polygenic factors influencing recombination.
Main Methods:
- Selection of Bombyx mori lines with high (H) and low (L) recombination rates.
- Analysis of F(1) crosses and backcrosses to assess genetic effects (additive, dominance).
- Measurement of recombination rates in cis and trans configurations, and assessment of viability.
Main Results:
- Recombination modifiers affected recombination frequency between p(S) and Y loci on chromosome 2, but not between pe and re loci on chromosome 5.
- No cytoplasmic maternal effects or differences in modifier activity between marked and unmarked chromosomes were detected.
- In the low recombination line, modifiers acted as polygenic factors, not gross chromosomal aberrations, with no impact on viability.
Conclusions:
- Recombination modifiers in Bombyx mori are primarily polygenic, localized on chromosome 2.
- These modifiers specifically alter recombination frequencies at certain loci without affecting overall viability.
- The genetic architecture of recombination rate variation is complex and locus-specific.
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