New records of freshwater Algae and Cyanobacteria from mountain streams of Córdoba (Argentina)

Constant collection surveys of freshwater Algae and Cyanobacteria in central Argentinastreams have revealed new identities. This study reports for the first time six species for Córdoba Province and five for Argentina. Biodiversity description of the streams of central Argentina is crucial for the development of conservation activities. In this study the record of new species for this region and for Argentina highlights the relevance of further research to help improving knowledge of the diversity andecology in this hydrographic system.Fil: Daga, Ines Claudia. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Diversidad Biológica y Ecológica; ArgentinaFil: Soteras, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Daniele, Graciela María. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Diversidad Biológica y Ecológica; ArgentinaFil: Dominguez, Laura Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

Comunidad de cianobacterias edáficas de suelos post-incendios en Sierras Chicas de la provincia de Córdoba, Argentina

Cyanobacteria are oxygenic phototrophic organisms that possess a high adaptive capacity to different environments, allowing them to pioneer terrestrial ecosystems. The objective of this study was to compare the cyanobacterial community in two areas of secondary mountain forest: one seven days after a fire (post-fire soil) and another nearby without fire (control soil). The collected samples were cultivated for 8 weeks under controlled conditions. A total of 35 taxa were identified: 2 unicellular, 24 filamentous without heterocytous, and 9 with heterocytous cyanobacteria; 13 of them represent the first record for soils in Córdoba. Microcoleus vaginatus was the most frequent taxon, along with Scytonema hoffmannii, Desmonostoc muscorum, and Nostoc commune, which persisted until the end of the experiment. The presence of exclusive organisms such as Calothrix brevissima, Chlorogloeopsis fritschii, and Cylindrospermum muscicola in the control soils highlights their sensitivity to this type of disruptive event in the community. The availability of nitrogen, CO content, and pH are the physicochemical soil variables that define the community structure. This work is contributing to increase our knowledge of soil restoration after forest fires.Las cianobacterias son los organismos fototróficos oxigénicos que poseen una alta capacidad adaptativa a diferentes ambientes, lo cual les permite ser pioneros en los ecosistemas terrestres. El objetivo del trabajo fue comparar la comunidad de cianobacterias en dos zonas de bosque serrano secundario, uno a siete días de ocurrido un incendio (suelo postfuego) y otra próxima sin incendio (suelo testigo). Las muestras extraídas se cultivaron durante 8 semanas en condiciones controladas. Se identificaron un total de 35 taxones: 2 unicelulares, 24 filamentosas sin heterocitos y 9 con heterocitos; 13 de ellos constituyen primera cita para suelos de Córdoba. Microcoleus vaginatus fue el taxón más frecuente, junto con Scytonema hoffmannii, Desmonostoc muscorum y Nostoc commune permanecieron hasta finalizar el ensayo. Se destaca la presencia de organismos exclusivos tales como: Calothrix brevissima, Chlorogloeopsis fritschii y Cylindrospermum muscicola en los suelos testigos, serían los taxones sensibles a este tipo de eventos disruptivos en la comunidad. La disponibilidad de nitrógeno, contenido de CO y pH son las variables físico-químicas del suelo que definen la estructura de la comunidad. Se considera que este trabajo aporta valiosa información para el avance del conocimiento de la restauración de suelos luego de los incendios forestales

Algae and cyanobacteria in the rhizosphere of lead accumulator plants

Las especies de algas y cyanobacteria que crecen en sitios contaminados pueden acumular altas concentraciones de metales pesados.En este trabajo se propuso a) caracterizar la comunidad de algas y cyanobacteria y b) evaluar el efecto del plomo (Pb) sobre la composición de algas presentes en la rizosfera de plantas capaces de acumular Pb en la provincia de Córdoba. Se tomaron muestras de suelo de la rizosfera de Sorghum halepense, Bidenspilosa y Tagetes minuta en sitios con diferentes niveles de Pb. En el laboratorio,el suelo se sembró en cápsulas con medio de Watanabe esterilizado. Los cultivos crecieron 9 semanas. Se identificó en el tiempo y analizó la frecuencia relativa final de las algas y cyanobacteria. En suelos contaminados se identificaron 24 especies de Cyanobacteria,Chloroplastida y Xanthophyceae. Las cyanobacteria con heterocitos Cylindrospermum muscicola, Nostoc commune y Calothrix clavata registraron una frecuencia media relativa (entre 21 y 60%). Trebouxia parmeliae (Chloroplastida)y Vaucheria sp. (Xanthophyceae) estuvieron presentes en los suelos con mayor nivel de Pb. La mayor parte de las especies se concentraron en los niveles más bajos de Pb. Se observó un efecto negativo del Pb sobre la riqueza de especies de algas y cyanobacteria en la rizosfera de las plantas evaluadas. En base a la composición de la comunidad de algas y cyanobacteria del suelo se determinaron grandes grupos que podrían ser considerados como comunidades tolerantes y no tolerantes a la contaminación de Pb.Fil: Becerra, Alejandra Gabriela. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Daga, Ines Claudia. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Diversidad Biológica y Ecológica; ArgentinaFil: Murialdo, Raquel Carmen. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Hidráulica; ArgentinaFil: Faggioli, Valeria Soledad. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Menoyo, Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; ArgentinaFil: Salazar, María Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

Desafíos alimentarios para un mundo que envejece

N/

An explainable model of host genetic interactions linked to COVID-19 severity

We employed a multifaceted computational strategy to identify the genetic factors contributing to increased risk of severe COVID-19 infection from a Whole Exome Sequencing (WES) dataset of a cohort of 2000 Italian patients. We coupled a stratified k-fold screening, to rank variants more associated with severity, with the training of multiple supervised classifiers, to predict severity based on screened features. Feature importance analysis from tree-based models allowed us to identify 16 variants with the highest support which, together with age and gender covariates, were found to be most predictive of COVID-19 severity. When tested on a follow-up cohort, our ensemble of models predicted severity with high accuracy (ACC = 81.88%; AUCROC = 96%; MCC = 61.55%). Our model recapitulated a vast literature of emerging molecular mechanisms and genetic factors linked to COVID-19 response and extends previous landmark Genome-Wide Association Studies (GWAS). It revealed a network of interplaying genetic signatures converging on established immune system and inflammatory processes linked to viral infection response. It also identified additional processes cross-talking with immune pathways, such as GPCR signaling, which might offer additional opportunities for therapeutic intervention and patient stratification. Publicly available PheWAS datasets revealed that several variants were significantly associated with phenotypic traits such as "Respiratory or thoracic disease", supporting their link with COVID-19 severity outcome.A multifaceted computational strategy identifies 16 genetic variants contributing to increased risk of severe COVID-19 infection from a Whole Exome Sequencing dataset of a cohort of Italian patients

The polymorphism L412F in TLR3 inhibits autophagy and is a marker of severe COVID-19 in males

The polymorphism L412F in TLR3 has been associated with several infectious diseases. However, the mechanism underlying this association is still unexplored. Here, we show that the L412F polymorphism in TLR3 is a marker of severity in COVID-19. This association increases in the sub-cohort of males. Impaired macroautophagy/autophagy and reduced TNF/TNFα production was demonstrated in HEK293 cells transfected with TLR3L412F-encoding plasmid and stimulated with specific agonist poly(I:C). A statistically significant reduced survival at 28 days was shown in L412F COVID-19 patients treated with the autophagy-inhibitor hydroxychloroquine (p = 0.038). An increased frequency of autoimmune disorders such as co-morbidity was found in L412F COVID-19 males with specific class II HLA haplotypes prone to autoantigen presentation. Our analyses indicate that L412F polymorphism makes males at risk of severe COVID-19 and provides a rationale for reinterpreting clinical trials considering autophagy pathways. Abbreviations: AP: autophagosome; AUC: area under the curve; BafA1: bafilomycin A1; COVID-19: coronavirus disease-2019; HCQ: hydroxychloroquine; RAP: rapamycin; ROC: receiver operating characteristic; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2; TLR: toll like receptor; TNF/TNF-α: tumor necrosis factor

SARS-CoV-2 susceptibility and COVID-19 disease severity are associated with genetic variants affecting gene expression in a variety of tissues

Variability in SARS-CoV-2 susceptibility and COVID-19 disease severity between individuals is partly due to genetic factors. Here, we identify 4 genomic loci with suggestive associations for SARS-CoV-2 susceptibility and 19 for COVID-19 disease severity. Four of these 23 loci likely have an ethnicity-specific component. Genome-wide association study (GWAS) signals in 11 loci colocalize with expression quantitative trait loci (eQTLs) associated with the expression of 20 genes in 62 tissues/cell types (range: 1:43 tissues/gene), including lung, brain, heart, muscle, and skin as well as the digestive system and immune system. We perform genetic fine mapping to compute 99% credible SNP sets, which identify 10 GWAS loci that have eight or fewer SNPs in the credible set, including three loci with one single likely causal SNP. Our study suggests that the diverse symptoms and disease severity of COVID-19 observed between individuals is associated with variants across the genome, affecting gene expression levels in a wide variety of tissue types

Pom1 regulates the assembly of Cdr2-Mid1 cortical nodes for robust spatial control of cytokinesis

Proper division plane positioning is essential to achieve faithful DNA segregation and to control daughter cell size, positioning, or fate within tissues. In Schizosaccharomyces pombe, division plane positioning is controlled positively by export of the division plane positioning factor Mid1/anillin from the nucleus and negatively by the Pom1/DYRK (dual-specificity tyrosine-regulated kinase) gradients emanating from cell tips. Pom1 restricts to the cell middle cortical cytokinetic ring precursor nodes organized by the SAD-like kinase Cdr2 and Mid1/anillin through an unknown mechanism. In this study, we show that Pom1 modulates Cdr2 association with membranes by phosphorylation of a basic region cooperating with the lipid-binding KA-1 domain. Pom1 also inhibits Cdr2 interaction with Mid1, reducing its clustering ability, possibly by down-regulation of Cdr2 kinase activity. We propose that the dual regulation exerted by Pom1 on Cdr2 prevents Cdr2 assembly into stable nodes in the cell tip region where Pom1 concentration is high, which ensures proper positioning of cytokinetic ring precursors at the cell geometrical center and robust and accurate division plane positioning

A first update on mapping the human genetic architecture of COVID-19

peer reviewe