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Gonzalez-Montelongo, R.

Publications and source records attributed to Gonzalez-Montelongo, R..

7 recordsLinked to original sources

Taming Darwin's conundrum: On the role of phylogenetic and functional differentiation in plant naturalization on oceanic islands

O_LIBiological invasions are a major threat to global biodiversity, particularly on oceanic islands and their unique and fragile biotas. However, the complexity of the processes underlying invasions has prevented the identification of general patterns explaining why some plant species successfully establish and spread beyond their native ranges. C_LIO_LIWe investigated Darwins naturalization conundrum in the most species-rich angiosperm family of the Canary Islands, considering two invasion stages across two spatial scales. Using a high-resolution phylogeny covering the Asteraceae species from the archipelago and functional traits measured from fresh specimens, we calculated phylogenetic and functional distances of invasive and noninvasive introduced species to natives. C_LIO_LIOur findings reveal that successful introduced Asteraceae species were phylogenetically distant from native relatives, with invasive species even more distantly related than noninvasive introduced species to their closest native relative. Functionally, noninvasive species were distinct, while invasive species showed unexpected similarity to native species. These patterns were consistent across spatial scales. C_LIO_LIThis study underscores the importance of a multidimensional approach to understanding plant invasion success. Identifying key patterns driving biological invasions is crucial for developing effective strategies against future ecological disruptions on islands. C_LI

ecology↗

Benchmarking of bioinformatics tools for the hybrid de novo assembly of human whole-genome sequencing data

Accurate and complete de novo assembled genomes sustain variant identification and catalyze the discovery of new genomic features and biological functions. However, accurate and precise de novo assemblies of large and complex genomes remains a challenging task. Long-read sequencing data alone or in hybrid mode combined with more accurate short-read sequences facilitate the de novo assembly of genomes. A number of software exists for de novo genome assembly from long-read data although specific performance comparisons to assembly human genomes are lacking. Here we benchmarked 11 different pipelines including four long-read only assemblers and three hybrid assemblers, combined with four polishing schemes for de novo genome assembly of a human reference material sequenced with Oxford Nanopore Technologies and Illumina. In addition, the best performing choice was validated in a non-reference routine laboratory sample. Software performance was evaluated by assessing the quality of the assemblies with QUAST, BUSCO, and Merqury metrics, and the computational costs associated with each of the pipelines were also assessed. We found that Flye was superior to all other assemblers, especially when relying on Ratatosk error-corrected long-reads. Polishing improved the accuracy and continuity of the assemblies and the combination of two rounds of Racon and Pilon achieved the best results. The assembly of the non-reference sample showed comparable assembly metrics as those of the reference material. Based on the results, a complete optimal analysis pipeline for the assembly, polishing, and contig curation developed on Nextflow is provided to enable efficient parallelization and built-in dependency management to further advance in the generation of high-quality and chromosome-level human assemblies.

bioinformatics↗

A benchmarking of human Y-chromosomal haplogroup classifiers from whole-genome and whole-exome sequence data

The non-recombinant region of the Y chromosome (NRY) contains a great number of polymorphic markers that allows to accurately reconstruct pedigree relationships and retrieve ancestral information from study samples. The analysis of NRY is typically implemented in anthropological, medical, and forensic studies. High-throughput sequencing (HTS) has profoundly increased the identification of genetic markers in the NRY genealogy and has prompted the development of automated NRY haplogroup classification tools. Here, we present a benchmarking study of five command-line tools for NRY haplogroup classification. The evaluation was done using empirical short-read HTS data from 50 unrelated donors using paired data from whole-genome sequencing (WGS) and whole-exome sequencing (WES) experiments. Besides, we evaluate the performance of the top-ranked tool in the classification of data of third generation HTS obtained from a subset of donors. Our findings demonstrate that WES can be an efficient approach to infer the NRY haplogroup, albeit generally providing a lower level of genealogical resolution than that recovered by WGS. Among the tools evaluated, YLeaf offers the best performance for both WGS and WES applications. Finally, we demonstrate that YLeaf is able to correctly classify all samples sequenced with nanopore technology from long noisy reads.

genomics↗

Transactive response DNA-binding Protein (TDP-43) regulates early HIV-1 entry and infection.

The transactive response DNA-binding protein (TDP-43) is an important regulator of mRNA, being reported to stabilize the anti-HIV factor, histone deacetylase 6 (HDAC6). However, little is known about the role of TDP-43 in HIV infection. In this work, we seek for the TDP-43 function on regulating CD4+ T cell permissibility to HIV infection. We observed that over-expression of wt-TDP-43 in CD4+ T cells stabilized HDAC6, increasing mRNA and the protein levels of this antiviral enzyme. Under this experimental condition, HIV-1 infection was impaired, independently of the viral envelope glycoprotein (Env) complex tropism. The results obtained by using an HIV-1 Env-mediated cell-to-cell fusion model, under the same experimental conditions, suggest that the increase in TDP-43 levels negatively affects the viral Env fusion capacity. Moreover, the specific siRNA silencing of endogenous TDP-43 in target cells lead to a significant decrease in the levels of HDAC6 which consistently induces an increase in the fusogenic and infection activities of the HIV-1 Env. These observations were confirmed by using primary viral Envs from HIV+ individuals with different clinical phenotypes. An increase in the level of expression of wt-TDP-43 strongly reduced the Envs infection activity of viremic non-progressors (VNP) and rapid progressors (RP) HIV+ individuals down to the levels of the inefficient HIV-1 Envs from long-term non-progressor elite controllers (LTNP-EC) individuals. On the contrary, low levels of endogenous TDP-43, obtained after specific siRNA-TDP-43 knocking-down, significantly favors the infection activity of primary HIV-1 Envs of VNP and RP individuals, leading to an increase in the infection ability of the primary HIV-1/LTNP-EC Envs. Based on this evidence, we interpret that TDP-43 conditions cell permissibility to HIV infection by affecting viral Env fusion and infection capacities, at least by altering the cellular levels of the antiviral enzyme HDAC6.

immunology↗

A benchmarking of human mitochondrial DNA haplogroup classifiers from whole-genome and whole-exome sequence data

The mitochondrial genome (mtDNA) is of interest for a range of fields including evolutionary, forensic, and medical genetics. Human mitogenomes can be classified into evolutionary related haplogroups that provide ancestral information and pedigree relationships. Because of this and the advent of high-throughput sequencing (HTS) technology, there is a diversity of bioinformatic tools for haplogroup classification. We present a benchmarking of the 11 most salient tools for human mtDNA classification using empirical whole-genome (WGS) and whole-exome (WES) short-read sequencing data from 36 unrelated donors. Besides, because of its relevance, we also assess the best performing tool in third-generation long noisy read WGS data obtained with nanopore technology for a subset of the donors. We found that, for short-read WGS, most of the tools exhibit high accuracy for haplogroup classification irrespective of the input file used for the analysis. However, for short-read WES, Haplocheck and MixEmt were the most accurate tools. Based on the performance shown for WGS and WES, and the accompanying qualitative assessment, Haplocheck stands out as the most complete tool. For third-generation HTS data, we also showed that Haplocheck was able to accurately retrieve mtDNA haplogroups for all samples assessed, although only after following assembly-based approaches (either based on a referenced-based assembly or a hybrid de novo assembly). Taken together, our results provide guidance for researchers to select the most suitable tool to conduct the mtDNA analyses from HTS data.

genomics↗

Shallow MinION sequencing to assist de novo assembly of the Streptococcus agalactiae genome

Despite the reduced read length, the so-called Next-Generation Sequencing (NGS) of second-generation has allowed rapid and complete genome characterization of many species. MinION (Oxford Nanopore Technologies), a portable third-generation NGS device, enables sequencing of long DNA fragments at low cost. Here we used a low-coverage MinION sequencing in combination with short-read NGS to improve genome assembly. We tested this possibility by using MinION R9.0 with Rapid 1D kit and MiSeq with >300X paired-end 300 bp reads (Illumina, Inc.) for the genome assembly of a Streptococcus agalactiae clinical isolate (2.2 Mb). With as few as 1,171 MinION reads that covered the genome at 2.4X (the longest read being 186 Kb long), the hybrid assembly combining MinION and Illumina reads increased the N50 by 4.9-fold compared to the assembly using Illumina data alone. Almost 50% of the genome was represented into a single contig (1.02 Mb). Besides, this allowed the full reconstruction of mobile elements, including a plasmid, and improved gene annotation. Taken together, our results support that shallow MinION sequencing combined with high-throughput second-generation NGS constitutes a cost-efficient strategy for the assembly of whole genomes.

genomics↗

Mitogenomes illuminate the origin and migration patterns of the indigenous people of the Canary Islands

The Canary Islands indigenous people have been the subject of substantial archaeological, anthropological, linguistic and genetic research pointing to a most probable North African Berber source. However, neither agreement about the exact point of origin nor a model for the indigenous colonization of the islands has been established. To shed light on these questions, we analyzed 48 ancient mitogenomes from 25 archaeological sites from the seven main islands. Most lineages observed in the ancient samples have a Mediterranean distribution, and belong to lineages associated with the Neolithic expansion in the Near East and Europe (T2c, J2a, X3a...). This phylogeographic analysis of Canarian indigenous mitogenomes, the first of its kind, shows that some lineages are restricted to Central North Africa (H1cf, J2a2d and T2c1d3), while others have a wider distribution, including both West and Central North Africa, and, in some cases, Europe and the Near East (U6a1a1, U6a7a1, U6b, X3a, U6c1). In addition, we identify four new Canarian-specific lineages (H1e1a9, H4a1e, J2a2d1a and L3b1a12) whose coalescence dates correlate with the estimated time for the colonization of the islands (1st millennia CE). Additionally, we observe an asymmetrical distribution of mtDNA haplogroups in the ancient population, with certain haplogroups appearing more frequently in the islands closer to the continent. This reinforces results based on modern mtDNA and Y-chromosome data, and archaeological evidence suggesting the existence of two distinct migrations. Comparisons between insular populations show that some populations had high genetic diversity, while others were probably affected by genetic drift and/or bottlenecks. In spite of observing interinsular differences in the survival of indigenous lineages, modern populations, with the sole exception of La Gomera, are homogenous across the islands, supporting the theory of extensive human mobility after the European conquest.

genetics↗