Comparison of Mitochondrial Genome Arrangement of Labeorohita with Some Selected Vertebrae Species.

Abstract

The mitochondrial genome of Labeorohita serves as a microcosm for exploring genetic diversity and evolutionary relationships within vertebrates. Through comprehensive analysis of the mitochondrial genome, encompassing 37 genes including protein-coding genes (PCGs), transfer RNA (tRNA), and ribosomal RNA (rRNA), we elucidated its organization and compared it with other vertebrate taxa. Our investigation revealed a compact mitochondrial genome of approximately 16 kb, comprising 13 PCGs, 22 tRNA genes, and 2 rRNA genes, with a distinctive dispersed loop region (D-loop). Notably, the arrangement of PCGs formed three distinct clusters, shared across Labeo species, suggesting evolutionary conservation within the genus. Comparative analyses with other osteichthyes species corroborated this conservation, underscoring L. rohita‘s representative status within the class. Furthermore, comparisons with chondrichthyes, lungfish, amphibians, reptiles, birds, and mammals unveiled evolutionary trends in mitochondrial genome organization. Noteworthy findings include the unique replication origin in lungfish and amphibians, and transposition events in birds. Phylogenetic reconstructions based on mitochondrial gene sequences affirmed the close relationship between lungfish and amphibians, supporting lungfish as the closest relatives of class Amphibia. In summary, our study provides comprehensive insights into the mitochondrial genome organization of L. rohita and its implications for vertebrate evolution. The findings contribute to a deeper understanding of genetic diversity and evolutionary relationships within vertebrates, with potential applications in taxonomy, conservation, and evolutionary biology.