Studying sleep orthologs in Epsilonproteobacteria through an evolutionary lens: investigating sleep mysteries through phylogenomics

The current study employed phylogenomic methods to examine sleep-related genes’ evolutionary role and significance in Sulfurimonas paralvinellae of the Epsilonproteobacteria class. This has facilitated the identification of conserved sleep orthologs, including DnaK (Hsp70), serine hydroxymethyltransferase (SHMT), and potassium channel family proteins, exhibiting sequence similarities ranging from 39.13% to 61.45%. These findings align with prior research indicating that chaperones and ion channels are conserved during sleep. This was demonstrated by the observation that proteins with fewer domains exhibited more significant conservation than others, such as adenylate kinase (AK). Distinct adaptations in bifunctional protein—serine/threonine kinases and phosphatases were linked to S. paralvinellae, an extremophilic organism adapted to high-pressure and/or high-temperature conditions, indicating functional divergence influenced by the organism’s environment. The Gene Ontology study results indicated catalytic activity, potassium channel function, and cellular processes, underscoring the significance of ion channels in regulating the sleep–wake cycle. Furthermore, the categories not recognized as particularly significant for the over-represented genes encompassed metabolic and signal transduction categories, suggesting enhanced functional flexibility within this protein subfamily. The findings emphasize that orthologous interactions are complex and influenced by subfunctionalization and neofunctionalization of ecology and evolution. These findings enhance the existing understanding of the evolution of sleep-related genes and their association with metabolic and environmental changes, providing a foundation for subsequent experimental investigations and cross-taxonomic comparisons.