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Updated: Sep 29, 2025
15:27
Extracting DNA from the Gut Microbes of the Termite Zootermopsis Angusticollis and Visualizing Gut Microbes
Published on: May 28, 2007
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Differential Selection on Caste-Associated Genes in a Subterranean Termite.
Julianne M Radford1, David Chen1, Anna M Chernyshova1
1Department of Biology, Western University, London, ON N6A 5B7, Canada.
Insects
|March 24, 2022
Summary
RNA analysis reveals caste-specific advantages in termites. Soldier genes show high selection, suggesting kin selection, while invasion impacts on diversity are unclear.
Area of Science:
- Evolutionary biology
- Social insect genetics
- Molecular evolution
Background:
- RNA content analysis can reveal genetic events in social insects.
- Eastern subterranean termites (Reticulitermes flavipes) exhibit distinct castes and populations.
Purpose of the Study:
- To analyze RNA content for caste-specific genetic advantages in Reticulitermes flavipes.
- To investigate the impact of invasion and unicoloniality on genetic diversity at the RNA level.
Main Methods:
- Utilized cDNA libraries from different castes (nymph, worker, soldier) and populations (Toronto, Raleigh, Boston).
- Analyzed single nucleotide variants (SNVs) and calculated the dN/dS ratio (ratio of nonsynonymous to synonymous substitutions).
Main Results:
- SNV counts were similar across castes but dN/dS ratios varied, indicating caste-specific advantages.
- Soldier caste genes exhibited a high dN/dS ratio (~4.3), suggesting positive selection, higher than other castes (~1.7–1.8).
- Population SNV counts differed, but not as expected; the invasive Toronto population showed no unique patterns, obscuring bottleneck effects.
Conclusions:
- Soldier-biased gene selection is likely indirect, mediated by kin selection.
- Behavioral changes in urban-invading termites (unicoloniality) may be independent of diversity loss expected from invasion bottlenecks.
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