Abstract
In-Silico Investigation of Fungal Sequences in Myxozoan and Cnidarian Genomes: Evidence of Horizontal Gene Transfer and Evolutionary Implications
Introduction
Horizontal gene transfer (HGT) is increasingly recognized as a significant driver of evolutionary innovation across diverse taxa, including eukaryotes. Notably, fungal sequences detected within the genomes of myxozoans, specialized metazoan parasites within Cnidaria, suggest complex evolutionary interactions between these organisms. This study systematically investigates fungal-derived genes within myxozoan genomes, examining potential transfer mechanisms, evolutionary implications, and functional significance, providing insights relevant to parasite-host interactions and adaptive metabolic strategies.
Materials and Methods
Genome assemblies for multiple myxozoan species were retrieved from the GenBank database, and fungal genomes from extensive GenBank datasets were employed to identify homologous sequences via BLAST searches. Comparative genomics and phylogenetic analyses (maximum likelihood and Bayesian inference) were performed using MEGA and MrBayes to assess phylogenetic incongruence indicative of HGT. Alien Index calculations and genomic context analyses (codon usage bias, GC content, association with mobile elements) supported candidate validation. Functional annotations, structural modeling, and interaction network analyses provided deeper insights into gene functionality.
Results
Multiple fungal-origin genes were confirmed in myxozoan genomes, including carbohydrate-active enzymes, 6-phosphofructokinase, aquaporins, and ABC transporter ATP-binding proteins, implicating diverse metabolic and physiological roles. Transfer mechanisms identified included HGT mediated by environmental uptake and symbiotic interactions. Structural modeling and network analyses indicated functional integration and potential evolutionary advantages in metabolic adaptation and host-parasite interactions. These findings underscore the extensive role of fungal genetic material in myxozoan evolution, highlighting intricate evolutionary dynamics facilitated by horizontal gene transfers.
Conclusion
Through horizontal gene transfer (HGT), fungal-origin genes in myxozoan genomes appear to play a significant evolutionary role.
Funded by São Paulo Research Foundation – FAPESP (Thematic Project #2018/24980-8; Postdoctoral fellowship # 2023/12298-6 – A.G.A. Ibrahim).