Biology subjects

Santiago-Alarcon, D.

Publications and source records attributed to Santiago-Alarcon, D..

3 recordsLinked to original sources

bioRxiv2024

A proposal for the quantum mechanical study of genomic mutations driven by environmental stressors

We propose a novel quantum statistical method to characterize DNA point mutations under the influence of UVC radiation, salinity, and temperature. We consider an open quantum system composed of an external environment -- high-energy photons -- coupled to the DNA molecule, and using energy considerations we estimate free parameters in a many-body Hamiltonian, to characterize critical behaviour in the system. The model presented here offers the advantage that one does not explicitly need to know each detail of the interaction between the base-pairs and the environment, by knowing whether the effect is to associate or dissociate the DNA molecule, one can incorporate it into the model. We show that by fine-tuning the free parameters, the model gives results that are within a biologically realistic range in the energetic scale. Importantly, specific heat values show that by coupling DNA to an external bath, the system dynamics leads to larger fluctuations at slightly lower temperatures. Following this research strategy, one could use experimental data to extract a correlation between specific heat and DNA changes, which would provide insight to predicting evolutionary changes.

evolutionary biology↗

bioRxiv2022

Great-tailed Grackles (Quiscalus mexicanus) as a tolerant host of avian malaria parasites

Great-tailed Grackles (Quiscalus mexicanus) are a social, polygamous bird species whose populations have rapidly expanded their geographic range across North America over the past century. Before 1865, Great-tailed Grackles were only documented in Central America, Mexico, and southern Texas in the USA. Given the rapid northern expansion of this species, it is relevant to study its role in the dynamics of avian blood parasites. Here, 87 Great-tailed grackles in Arizona (a population in the new center of the range) were screened for haemosporidian parasites using microscopy and PCR targeting the parasite mitochondrial cytochrome b gene. Individuals were caught in the wild from January 2018 until February 2020. Haemosporidian parasite prevalence was 60.9% (53/87). A high Plasmodium prevalence was found (59.8%, 52/87), and one grackle was infected with Haemoproteus (Parahaemoproteus) sp. (lineage SIAMEX01). Twenty-one grackles were infected with P. cathemerium, sixteen with P. homopolare, four with P. relictum (strain GRW04), and eleven with three different genetic lineages of Plasmodium spp. that have not been characterized to species level (MOLATE01, PHPAT01, and ZEMAC01). Gametocytes were observed in birds infected with three different Plasmodium lineages, revealing that grackles are competent hosts for some parasite species. This study also suggests that grackles are highly susceptible and develop chronic infections consistent with parasite tolerance, making them competent to transmit some generalist haemosporidian lineages. It can be hypothesized that, as the Great-tailed Grackle expands its geographic range, it may affect local bird communities by increasing the transmission of local parasites but not introducing new species into the parasite species pool.

zoology↗

bioRxiv2020

American mammals susceptibility to dengue according to geographical, environmental and phylogenetic distances

Many human emergent and re-emergent diseases have a sylvatic cycle. Yet, little effort has been put into discovering and modeling the wild mammal reservoirs of dengue (DENV), particularly in the Americas. Here, we show a species-level susceptibility prediction to dengue of wild mammals in the Americas as a function of the three most important biodiversity dimensions (ecological, geographical, and phylogenetic spaces), using machine learning protocols. Model predictions showed that different species of bats would be highly susceptible to DENV infections, where susceptibility mostly depended on phylogenetic relationships among hosts and their environmental requirement. Mammal species predicted as highly susceptible coincide with sets of species that have been reported infected in field studies, but it also suggests other species that have not been previously considered or that have been captured in low numbers. Also, the environment (i.e., the distance between the species optima in bioclimatic dimensions) in combination with geographic and phylogenetic distance is highly relevant in predicting susceptibility to DENV in wild mammals. Our results agree with previous modeling efforts indicating that temperature is an important factor determining DENV transmission, and provide novel insights regarding other relevant factors and the importance of considering wild reservoirs. This modeling framework will aid in the identification of potential DENV reservoirs for future surveillance efforts.

ecology↗