| Full text | |
| Author(s): |
Total Authors: 2
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| Affiliation: | [1] Univ Estadual Campinas, Dept Genet Evolut Microbiol & Immunol, Lab Evolutionary Genom, Campinas, SP - Brazil
Total Affiliations: 1
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| Document type: | Journal article |
| Source: | Molecular Immunology; v. 117, p. 131-138, JAN 2020. |
| Web of Science Citations: | 0 |
| Abstract | |
V(D)J recombination is a process of somatic recombination catalyzed by proteins encoded by RAG1 and RAG2 genes, both restricted to the genome of jawed vertebrates. Their proteins constitute the enzymatic core of V(D)J recombination machinery and are crucial for jawed vertebrate adaptive immunity. Mammals possess great ecological diversity, and their complex evolutionary history associated with radiation to different environments presented many distinct pathogenic challenges from these different habitats. Cetaceans comprise a mammalian order of fully aquatic mammals that have arisen from a complete terrestrial ancestor and, accordingly, was confronted with challenges from changing environmental pathogens while they transitioned from land to sea. In this study we undertook molecular evolutionary analyses of RAG1 and RAG2 genes, exploring the possible role of natural selection acting on these genes focusing on the cetacean lineage. We performed phylogenetic reconstructions on IQ-TREE, together with selection analyses in the codeml program of the PAML package, and in the FITMODEL program for codon evolution and switching on both the RAG1 and RAG2 genes. Our findings demonstrate that RAG1 and RAG2 remained fairly conserved among tetrapods, with purifying selection acting on both genes, with evidence for a few punctuated shifts in nucleotide substitution rates of both genes along tetrapod evolution. We demonstrate differential evolution in the closely linked genes RAG1 and RAG2 specifically in cetaceans. (AU) | |
| FAPESP's process: | 15/18269-1 - Using comparative genomics to understand convergent evolution of mammals: tracking the molecular footprints of the marine and riverine environment colonisation |
| Grantee: | Mariana Freitas Nery |
| Support Opportunities: | Research Grants - Young Investigators Grants |
| FAPESP's process: | 17/14831-2 - Molecular evolution of immune system genes in aquatic mammals: identifying molecular footprints of the colonization of new environment |
| Grantee: | Bruna Cristina Dias |
| Support Opportunities: | Scholarships in Brazil - Master |