Biology subjects

Opazo, J.

Publications and source records attributed to Opazo, J..

3 recordsLinked to original sources

bioRxiv2023

Evolution of ion channels in cetaceans a natural experiment in the tree of life

Cetaceans could be seen as a natural experiment within the tree of life in which a mammalian lineage changed from terrestrial to aquatic habitats. This shift involved extensive phenotypic modifications, which represent an opportunity to explore the genetic bases of phenotypic diversity. Furthermore, the availability of whole genome sequences in representative species of all main cetacean groups means that we are in a golden age for such studies. Among the different molecular systems that maintain cellular homeostasis, ion channels are crucial for the proper physiological functioning of all living species. This study aims to explore the evolution of ion channels during the evolutionary history of cetaceans. To do so, we created a bioinformatic pipeline to annotate the repertoire of ion channels in the genome of the species included in our sampling. Our main results show that cetaceans have on average, fewer protein-coding genes and a higher percentage of annotated ion channels than non-cetacean mammals. Signals of positive selection were detected in ion channels related to the heart, locomotion, visual and neurological phenotypes. Interestingly, we predict that the NaV1.5 ion channel of most toothed whales (odontocetes) is sensitive to tetrodotoxin (TTX), similar to NaV1.7, given the presence of tyrosine instead of cysteine, in a specific position of the ion channel. Finally, the gene turnover rate of the cetacean crown group is more than three times faster than non-cetacean mammals.

evolutionary biology↗

bioRxiv2021

Identification of multiple TAR DNA Binding Protein retropseudogene lineages during the evolution of primates

The TAR DNA Binding Protein (TARDBP) gene has gained attention in biomedicine after the discovery of several pathogenic mutations. The lack of knowledge about its evolutionary history contrasts with a large number of studies in the biomedical area. This study aimed to investigate the retrotransposition evolutionary dynamics associated with this gene in primates. We identified retropseudogenes that originated in the ancestors of anthropoids, catarrhines, and lemuriformes, i.e. the strepsirrhine clade that inhabit Madagascar. We also found species-specific retropseudogenes in the philippine tarsier, Bolivian squirrel monkey, capuchin monkey and vervet. Although retropseudogenes are not able to produce a functional protein, we can not rule out that they may represent genetic material upon which evolution acts on, especially with regulatory functions.

evolutionary biology↗

bioRxiv2017

Evolution of the α2-adrenoreceptors in vertebrates: ADRA2D is absent in mammals and crocodiles

Evolutionary studies of genes that have been functionally characterized and whose variation has been associated with pathological conditions represent an opportunity to understand the genetic basis of pathologies. 2-adrenoreceptors (ADRA2) are a class of G protein-coupled receptors that regulate several physiological processes including blood pressure, platelet aggregation, insulin secretion, lipolysis, and neurotransmitter release. This gene family has been extensively studied from a molecular/physiological perspective, yet much less is known about its evolutionary history. Accordingly, the goal of this study was to investigate the evolutionary history of 2-adrenoreceptors (ADRA2) in vertebrates. Our results show that in addition to the three well-recognized 2-adrenoreceptor genes (ADRA2A, ADRA2B and ADRA2C), we recovered a clade that corresponds to the fourth member of the 2-adrenoreceptor gene family (ADRA2D). We also recovered a clade that possesses two ADRA2 sequences found in two lamprey species. Furthermore, our results show that mammals and crocodiles are characterized by possessing three 2-adrenoreceptor genes, whereas all other vertebrate groups possess the full repertoire of 2-adrenoreceptor genes. Among vertebrates ADRA2D seems to be a dispensable gene, as it was lost two independent times during the evolutionary history of the group. Additionally, we found that most examined species possess the most common alleles described for humans; however, there are cases in which non-human mammals possess the alternative variant.

evolutionary biology↗