Mitochondrial Phylogenomics and Genome Evolution in Anura: Insights From Structure and Gene Order Rearrangements

Area of Science:

• Evolutionary Biology
• Genomics
• Zoology

Background:

• Mitochondrial genomes (mitogenomes) are valuable for phylogenetic studies due to their inheritance patterns and evolutionary rates.
• Anurans (frogs and toads) display significant mitogenome variability, but its evolutionary implications are not well understood.

Purpose of the Study:

• To reconstruct the anuran phylogeny using mitogenomic data.
• To investigate the evolution of gene order within anuran mitogenomes.
• To establish a robust mitogenomic framework for anuran evolutionary studies.

Main Methods:

• Phylogenomic reconstruction using 277 anuran mitogenomes.
• Comparative analysis of gene arrangement patterns (CREx).
• Divergence time estimation.

Main Results:

• Phylogenetic analyses resolved five major clades and confirmed Neobatrachia as monophyletic.
• Archaeobatrachians were found to be paraphyletic.
• Fifty-eight distinct gene arrangement patterns were identified, with some being lineage-specific.
• Anuran origins were dated to the Early-Late Triassic boundary, with major radiations in the Late Cretaceous to Early Neogene.

Conclusions:

• The study provides a robust mitogenomic framework for anuran phylogeny, resolving deep phylogenetic discordance.
• Novel patterns of mitogenomic gene order evolution were discovered.
• Findings lay the groundwork for investigating mechanisms of mitogenomic diversification and its role in anuran evolutionary success.