Project description:Boana comprises a diverse genus of Neotropical treefrogs, currently rearranged into seven taxonomic species groups. Although cytogenetic studies have demonstrated diversity in its representatives, the chromosomal mapping of repetitive DNA sequences is still scarce. In this study, Boana albopunctata, Boana faber, and Boana prasina were subjected to in situ localization of different repetitive DNA units to evaluate trends of chromosomal evolution in this genus. Boana faber and B. prasina had 2n=24 chromosomes, while B. albopunctata has 2n=22 and an intra-individual variation related to the presence/absence of one B chromosome. The location of 45S rDNA sites was different in the analyzed karyotypes, corroborating with what was found in the distinct phylogenetic groups of Boana. We presented the first description of 5S rDNA in a Boana species, which showed markings resulting from transposition/translocation mechanisms. In situ localization of microsatellite loci proved to be a helpful marker for karyotype comparison in Boana, commonly with cis accumulation in the heterochromatin. On the other hand, genomic dispersion of microsatellites may be associated with hitchhiking effects during the spreading of transposable elements. The obtained results corroborated the independent diversification of these lineages of species from three distinct phylogenetic groups of Boana.
| S-EPMC9827724 | biostudies-literature
Project description:Symbiotic skin bacteria of Boana prasina
Project description:In order to combat bacterial and cancer resistance, we identified peptides (pugnins) with dual antibacterial l-anticancer activity from the Boana pugnax (B. pugnax) skin transcriptome through in silico analysis. Pugnins A and B were selected owing to their high similarity to the DS4.3 peptide, which served as a template for their alignment to the B. pugnax transcriptome, as well as their function as part of a voltage-dependent potassium channel protein. The secondary peptide structure stability in aqueous medium was evaluated as well, and after interaction with the Escherichia coli (E. coli) membrane model using molecular dynamics. These pugnins were synthesized via solid-phase synthesis strategy and verified by Reverse phase high-performance liquid chromatography (RP-HPLC) and mass spectrometry. Subsequently, their alpha-helix structure was determined by circular dichroism, after which antibacterial tests were then performed to evaluate their antimicrobial activity. Cytotoxicity tests against cancer cells also showed selectivity of pugnin A toward breast cancer (MFC7) cells, and pugnin B toward prostate cancer (PC3) cells. Alternatively, flow cytometry revealed necrotic cell damage with a major cytotoxic effect on human keratinocytes (HaCaT) control cells. Therefore, the pugnins found in the transcriptome of B. pugnax present dual antibacterial-anticancer activity with reduced selectivity to normal eukaryotic cells.
Project description:Increases in the prevalence of multiply resistant microbes have necessitated the search for new molecules with antimicrobial properties. One noteworthy avenue in this search is inspired by the presence of native antimicrobial peptides in the skin of amphibians. Having the second highest diversity of frogs worldwide, Colombian anurans represent an extensive natural reservoir that could be tapped in this search. Among this diversity, species such as Boana pugnax (the Chirique-Flusse Treefrog) are particularly notable, in that they thrive in a diversity of marginal habitats, utilize both aquatic and arboreal habitats, and are members of one of few genera that are known to mount a robust immunological response against the fungus Batrachochytrium dendrobatidis, which has decimated the population of frogs worldwide. To search for molecules with potential antimicrobial activity, we have assembled and annotated a reference transcriptome from the skin of four wild captured B. pugnax from Antioquia, Colombia. Analysis of potential antimicrobial and immunological components was performed using ontology analyses, we identified several antimicrobial chemokines with particularly strong potential for exhibiting broadscale antimicrobial activities, as well as several genes related to rapid alteration of transcriptional (KRAB zinc finger protein) and phosphorylation (MAPK) responses to exogenous stressors. We also found eight families of transmembrane transport proteins, including sodium, potassium and voltage-dependent calcium channels, which will be invaluable in future studies aimed at more precisely defining the diversity and function of cationic antimicrobial peptides with alpha-helical structures. These data highlight the utility of frogs such as Boana pugnax in the search of new antimicrobial molecules. Moreover, the molecular datasets presented here allow us to expand our knowledge of this species and illustrate the importance of preserving the vast potential of Colombian biodiversity for the identification of useful biomolecules.