Regulatory logic and transposable element dynamics in nematode worm genomes

Area of Science:

• Evolutionary biology
• Genomics
• Molecular evolution

Background:

• Transposable elements (TEs) exhibit vast diversity in eukaryotes, yet evolutionary drivers remain unclear.
• Non-autonomous TEs depend on autonomous TEs for transposition machinery, creating complex regulatory interactions.

Purpose of the Study:

• To investigate how TE regulatory relationships influence TE diversity and population dynamics.
• To model the evolutionary consequences of different TE regulatory strategies.

Main Methods:

• Developed and simulated two mathematical models of TE regulation: shared regulation and parasitic regulation.
• Analyzed transposable element annotation in Caenorhabditis genomes, focusing on LINE/SINE and Mutator families.

Main Results:

• Parasitic TE regulation in outcrossing populations led to stable TE maintenance.
• Observed significant variation in autonomous-non-autonomous TE interactions within Caenorhabditis.
• Identified rapid mutational decay in non-autonomous TE sequences essential for transposition.

Conclusions:

• TE regulatory logic significantly impacts TE evolution and stability.
• Disparate regulatory rules govern individual TE families, particularly during early invasion stages.