Related Experiment Video
Updated: Jan 30, 2026

Immunofluorescent Staining for Visualization of Heterochromatin Associated Proteins in Drosophila Salivary Glands
Published on: August 21, 2021
Evolution of salivary glue genes in Drosophila species
Jean-Luc Da Lage1, Gregg W C Thomas2, Magalie Bonneau3
1UMR 9191 Évolution, Génomes, Comportement, Écologie. CNRS, IRD, Université Paris-Sud. Université Paris-Saclay, F-91198, Gif-sur-Yvette, France. jean-luc.da-lage@egce.cnrs-gif.fr.
Background:
At the very end of the larval stage Drosophila expectorate a glue secreted by their salivary glands to attach themselves to a substrate while pupariating. The glue is a mixture of apparently unrelated proteins, some of which are highly glycosylated and possess internal repeats. Because species adhere to distinct substrates (i.e. leaves, wood, rotten fruits), glue genes are expected to evolve rapidly.
Results:
We used available genome sequences and PCR-sequencing of regions of interest to investigate the glue genes in 20 Drosophila species. We discovered a new gene in addition to the seven glue genes annotated in D. melanogaster. We also identified a phase 1 intron at a conserved position present in five of the eight glue genes of D. melanogaster, suggesting a common origin for those glue genes. A slightly significant rate of gene turnover was inferred. Both the number of repeats and the repeat sequence were found to diverge rapidly, even between closely related species. We also detected high repeat number variation at the intrapopulation level in D. melanogaster.
Conclusion:
Most conspicuous signs of accelerated evolution are found in the repeat regions of several glue genes.
More Related Videos
07:09A Bioinformatics Pipeline for Investigating Molecular Evolution and Gene Expression using RNA-seq
Published on: May 28, 2021
10:31The Drosophila Imaginal Disc Tumor Model: Visualization and Quantification of Gene Expression and Tumor Invasiveness Using Genetic Mosaics
Published on: October 6, 2016
Related Concept Videos
Genome Size and the Evolution of New Genes
Genome Size and the Evolution of New Genes
Gene Evolution - Fast or Slow?
In contrast, regions which code...
Gene Evolution - Fast or Slow?
The Evidence for Evolution
Convergent Evolution