Mitochondrial Genomics and Phylogenetics in Teleost Fishes

Mitochondrial genomes of teleost fishes have long served as fundamental markers for unravelling evolutionary history and population structure. Typically comprising 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs and a non-coding control region, mitogenomes exhibit conserved gene order interspersed with lineage-specific rearrangements that inform phylogenetic inference. High mutation rates, maternal inheritance and relatively compact organisation facilitate large-scale comparative analyses across thousands of species. Advances in sequencing – in particular the adoption of long-read technologies – have revealed unexpected duplications, inversions and heteroplasmic variants that underpin adaptive traits, from cold tolerance in polar species to speciation events driven by ocean currents. Time-calibrated mitogenome phylogenies are refining the timing of major radiations, while comprehensive reference libraries are enhancing fisheries management, conservation genetics and species identification. Together, these developments underscore the central role of mitochondrial genomics in charting teleost diversity, biogeography and the genetic basis of adaptation.

Research from Nature Portfolio

Recent long-read assemblies of Antarctic notothenioid mitogenomes have uncovered extensive structural variation previously hidden by short-read methods. Within five species of icefish and related cold-adapted taxa, researchers discovered novel duplications of key protein-coding genes (notably ND6), transfer RNAs and control regions, alongside pervasive heteroplasmy within individual specimens. Inversion events and tandem repeats were documented in temperate relatives, signalling dynamic architectural evolution. These findings implicate mitogenome rearrangements and copy-number variants in the physiological adaptations required for survival in subzero environments, illustrating the power of high-resolution mitochondrial mapping for understanding the genomic underpinnings of thermal tolerance.

Mitochondrial Genomics and Phylogenetics in Teleost Fishes publication trend

The graph below shows the total number of articles in mitochondrial genomics and phylogenetics in teleost fishes across all publications each year (not limited to Nature Index journals).

Technical terms

Mitogenome: The complete mitochondrial DNA sequence, typically including 13 protein-coding genes, 22 tRNAs, two rRNAs and a control region.

Heteroplasmy: The presence of more than one mitochondrial DNA variant within an individual, often revealed by long-read sequencing.

Purifying selection: Evolutionary pressure that removes deleterious mutations from protein-coding genes, maintaining functional integrity.

Control region: A non-coding segment of the mitogenome involved in replication and transcriptional regulation, often rich in conserved sequence blocks.

Phylogenetics: The study of evolutionary relationships among species or lineages, often inferred from genetic sequence comparisons.

References

1. Mitogenomic Characterization and Phylogenetic Placement of African Hind, Cephalopholis taeniops: Shedding Light on the Evolution of Groupers (Serranidae: Epinephelinae). International Journal of Molecular Sciences (2024).
2. Endemic Radiation of African Moonfish, Selene dorsalis (Gill 1863), in the Eastern Atlantic: Mitogenomic Characterization and Phylogenetic Implications of Carangids (Teleostei: Carangiformes). Biomolecules (2024).
3. Novel mitochondrial genome rearrangements including duplications and extensive heteroplasmy could underlie temperature adaptations in Antarctic notothenioid fishes. Scientific Reports (2023).
4. Mitochondrial genome structure and composition in 70 fishes: a key resource for fisheries management in the South Atlantic. BMC Genomics (2024).
5. Structure and variation of the mitochondrial genome of fishes. BMC Genomics (2016).