Biology subjects

Ferreira, M.

Publications and source records attributed to Ferreira, M..

23 records · Page 2Linked to original sources

bioRxiv2021

Harbor porpoise losing its edges: genetic time series suggests a rapid population decline in Iberian waters over the last 30 years

Impact of climate changes on species is expected to be especially visible at the extremities of the species distribution, where they meet sub-optimal conditions. In Mauritania and Iberia, two genetically isolated populations of harbor porpoises form a distinct ecotype and are presumably locally adapted to the upwelling waters. By analyzing the evolution of mitochondrial genetic variation in the Iberian population between two temporal cohorts (1990-2002 vs. 2012-2015), we report a dramatic decrease in genetic diversity. Phylogenetic analyses including neighboring populations identified two porpoises in southern Iberia carrying a divergent haplotype close to the Mauritanian population, yet forming a distinctive lineage. This suggests that Iberian porpoises may not be as isolated as previously thought with immigration from Mauritania or an unknown population in between, but none from the northern ecotype. The rapid decline in the Iberian mitochondrial diversity may be driven by either genetic drift, or by a dramatic decline in census population size possibly resulting from environmental stochasticity, prey depletion, or acute fishery bycatches. These results illustrate the value of genetics time series to inform demographic trends and emphasize the urgent need for conservation measures to ensure the viability of this small harbor porpoise population in Iberia.

evolutionary biology↗

bioRxiv2021

Integration of differential gene expression with weighted gene correlation network analysis identifies genes whose expression is remodeled throughout physiological aging in mouse tissues

Gene expression alterations occur in all mouse tissues during aging, but recent works highlight minor rather than major dysregulation amplitude for most genes, questioning whether differentially expressed genes on their own provide deep insight into aging biology. To clarify this issue, we have combined differential gene expression with weighted gene correlation network analysis (WGCNA) to identify expression signatures accounting for the pairwise relations between gene expression profiles and the cumulative effect of genes with small fold- changes during aging in the brain, heart, liver, skeletal muscle, and pancreas of C57BL/6 mice. Functional enrichment analysis of the overlap of genes identified in both approaches showed that immunity-related responses, mitochondrial energy metabolism, tissue regeneration and detoxification are prominently altered in the brain, heart, muscle, and liver, respectively, reflecting an age-related global loss of tissue function. While data showed little overlap among the age-dysregulated genes between tissues, aging triggered common biological processes in distinct tissues, particularly proteostasis-related pathways, which we highlight as important features of murine tissue physiological aging.

genetics↗

bioRxiv2020

Computationally efficient whole genome regression for quantitative and binary traits

Genome-wide association analysis of cohorts with thousands of phenotypes is computationally expensive, particularly when accounting for sample relatedness or population structure. Here we present a novel machine learning method called REGENIE for fitting a whole genome regression model that is orders of magnitude faster than alternatives, while maintaining statistical efficiency. The method naturally accommodates parallel analysis of multiple phenotypes, and only requires local segments of the genotype matrix to be loaded in memory, in contrast to existing alternatives which must load genomewide matrices into memory. This results in substantial savings in compute time and memory usage. The method is applicable to both quantitative and binary phenotypes, including rare variant analysis of binary traits with unbalanced case-control ratios where we introduce a fast, approximate Firth logistic regression test. The method is ideally suited to take advantage of distributed computing frameworks. We demonstrate the accuracy and computational benefits of this approach compared to several existing methods using quantitative and binary traits from the UK Biobank dataset with up to 407,746 individuals.

genetics↗

bioRxiv2019

Evolutionary history of the porpoises (Phocoenidae) across the speciation continuum: a mitogenome phylogeographic perspective

Historical changes affecting food resources are a major driver of cetacean evolution. Small cetaceans like porpoises (Phocoenidae) are among the most metabolically challenged marine mammals and are particularly sensitive to changes in their food resources. The seven species of this family inhabit mostly temperate waters and constitute a textbook example of antitropical distribution. Yet, their evolutionary history remains poorly known despite major conservation issues threatening the survival of some porpoises (e.g., vaquita and Yangzte finless porpoises). Here, we reconstructed their evolutionary history across the speciation continuum, from intraspecific subdivisions to species divergence. Phylogenetic analyses of 63 mitochondrial genomes suggest that, like other toothed whales, porpoises radiated during the Pliocene in response to deep environmental changes. However, all intra-specific phylogeographic patterns were shaped during the Quaternary Glaciations. We observed analogous evolutionary patterns in both hemispheres associated with convergent adaptations to coastal versus oceanic environments. This result suggests that the mechanism(s) driving species diversification in the relatively well-known species from the northern hemisphere may apply also to the poorly-known southern species. In contrast to previous studies, we showed that the spectacled and Burmeisters porpoises share a more recent common ancestor than with the vaquita that diverged from southern species during the Pliocene. The low genetic diversity observed in the vaquita carried signatures of a very low population size throughout at least the last 5,000 years, leaving one single relict mitochondrial lineage. Finally, we observed unreported subspecies level divergence within Dalls, spectacled and Pacific harbor porpoises, suggesting a richer evolutionary history than previously suspected. These results provide a new perspective on the mechanism driving the adaptation and speciation processes involved in the diversification of cetacean species. This knowledge can illuminate their demographic trends and provide an evolutionary framework for their conservation.

evolutionary biology↗

bioRxiv2019

Genetic Diversity and Phylogenetic Relationships of Annual and Perennial Glycine Species

We estimated average genetic diversity of two Glycine annual and six perennial species based upon 76 orthologous gene sets and performed phylogenetic analysis, divergence analysis and tests for departure from neutrality of the eight species using 52 orthologous gene sets. In addition, 367 orthologous gene sets were used to estimate the relationships of 11 G. canescens accessions. Among the perennials, G. canescens showed the highest nucleotide diversity and the other perennials except G. tomentella had higher nucleotide diversity than the two annuals. Phylogenetic analysis of the Glycine showed a similar genome grouping with the previous report except G. cyrtoloba and G. stenophita formed a sister clade in the study. Divergence analysis supported the phylogenetic relationships, G. falcata was the most divergent from G. max, followed by G. cyrtoloba, G. syndetika, G. tomentella D3, G. stenophita and G. canescens. Neutrality selection tests within species showed that most genes were subjected to a recent directional selection due to a selective sweep or rapid population expansion. Although most gene sequence had negative and significant Tajimas D, the sequences were homogeneous in the levels of polymorphism and divergence between G. max and other Glycine species based on the HKA test, thus, Glycine perennials may have experienced very similar evolutionary selection as inferred by trans-specific mutation analysis. The greater genetic diversity of most perennial Glycine species and their origins from the warmer and drier climates of Australia suggested the perennials as potential sources of heat and drought resistance that will be of value in the face of climate change.

genetics↗