Plant transposons: contributors to evolution?

Area of Science:

• Genetics
• Evolutionary Biology
• Plant Science

Background:

• Plant transposable elements (TEs) are debated as either evolutionary drivers or genetic burdens.
• Hypotheses range from TEs as major evolutionary agents to them being primarily selfish DNA.

Purpose of the Study:

• To review the dual assessment of transposable elements (TEs) in species origin (selfish vs. useful DNA).
• To examine the role of gene function hierarchy and redundancy in TE activity.
• To explore TE-induced species formation in angiosperms, considering systematic and genetic species concepts.

Main Methods:

• Literature review and synthesis of existing research on transposable elements.
• Analysis of case studies from Zea mays and Antirrhinum majus.
• Discussion of theoretical frameworks for TE-driven evolution.

Main Results:

• TEs exhibit context-dependent roles, acting as selfish DNA in non-redundant genomic regions and sources of variation elsewhere.
• Research in Zea mays and Antirrhinum majus highlights the contrast between artificial and natural selection in TE activity.
• Potential synthesis areas include regressive evolution, ecotype, and cultivated plant origins.

Conclusions:

• Transposable elements significantly contribute to genetic variability and species formation.
• TE activity, particularly loss-of-function mutations, may explain the origin of many angiosperm morphospecies.
• Reconciling systematic and genetic species concepts is crucial for understanding TE-induced speciation.