17 research outputs found
Physiological, Biochemical, and Transcriptional Responses to Single and Combined Abiotic Stress in Stress-Tolerant and Stress-Sensitive Potato Genotypes
Potato production is often constrained by abiotic stresses such as drought and high temperatures which are often present in combination. In the present work, we aimed to identify key mechanisms and processes underlying single and combined abiotic stress tolerance by comparative analysis of tolerant and susceptible cultivars. Physiological data indicated that the cultivars Desiree and Unica were stress tolerant while Agria and Russett Burbank were stress susceptible. Abiotic stress caused a greater reduction of photosynthetic carbon assimilation in the susceptible cultivars which was associated with a lower leaf transpiration rate. Oxidative stress, as estimated by the accumulation of malondialdehyde was not induced by stress treatments in any of the genotypes with the exception of drought stress in Russett Burbank. Stress treatment resulted in increases in ascorbate peroxidase activity in all cultivars except Agria which increased catalase activity in response to stress. Transcript profiling highlighted a decrease in the abundance of transcripts encoding proteins associated with PSII light harvesting complex in stress tolerant cultivars. Furthermore, stress tolerant cultivars accumulated fewer transcripts encoding a type-1 metacaspase implicated in programmed cell death. Stress tolerant cultivars exhibited stronger expression of genes associated with plant growth and development, hormone metabolism and primary and secondary metabolism than stress susceptible cultivars. Metabolite profiling revealed accumulation of proline in all genotypes following drought stress that was partially suppressed in combined heat and drought. On the contrary, the sugar alcohols inositol and mannitol were strongly accumulated under heat and combined heat and drought stress while galactinol was most strongly accumulated under drought. Combined heat and drought also resulted in the accumulation of Valine, isoleucine, and lysine in all genotypes. These data indicate that single and multiple abiotic stress tolerance in potato is associated with a maintenance of CO2 assimilation and protection of PSII by a reduction of light harvesting capacity. The data further suggests that stress tolerant cultivars suppress cell death and maintain growth and development via fine tuning of hormone signaling, and primary and secondary metabolism. This study highlights potential targets for the development of stress tolerant potato cultivars
Multiple glacial refugia and contemporary dispersal shape the genetic structure of an endemic amphibian from the Pyrenees
Historical factors (colonization scenarios, demographic oscillations) and contemporary processes (population connectivity, current population size) largely contribute to shaping species’ present-day genetic diversity and structure. In this study, we use a combination of mitochondrial and nuclear DNA markers to understand the role of Quaternary climatic oscillations and present-day gene flow dynamics in determining the genetic diversity and structure of the newt Calotriton asper (Al. Dugès, 1852), endemic to the Pyrenees. Mitochondrial DNA did not show a clear phylogeographic pattern and presented low levels of variation. In contrast, microsatellites revealed five major genetic lineages with admixture patterns at their boundaries. Approximate Bayesian computation analyses and linear models indicated that the five lineages likely underwent separate evolutionary histories and can be tracked back to distinct glacial refugia. Lineage differentiation started around the Last Glacial Maximum at three focal areas (western, central and eastern Pyrenees) and extended through the end of the Last Glacial Period in the central Pyrenees, where it led to the formation of two more lineages. Our data revealed no evidence of recent dispersal between lineages, whereas borders likely represent zones of secondary contact following expansion from multiple refugia. Finally, we did not find genetic evidence of sex-biased dispersal. This work highlights the importance of integrating past evolutionary processes and present-day gene flow and dispersal dynamics, together with multilocus approaches, to gain insights into what shaped the current genetic attributes of amphibians living in montane habitats.info:eu-repo/semantics/publishedVersio
Multiple invasions, Wolbachia and human‑aided transport drive the genetic variability of Aedes albopictus in the Iberian Peninsula
Este artículo contiene 15 páginas, 7 figuras, 1 tabla.The Asian tiger mosquito, Aedes albopictus, is one of the most invasive species in the world. Native
to the tropical forests of Southeast Asia, over the past 30 years it has rapidly spread throughout
tropical and temperate regions of the world. Its dramatic expansion has resulted in public health
concerns as a consequence of its vector competence for at least 16 viruses. Previous studies showed
that Ae. albopictus spread has been facilitated by human-mediated transportation, but much remains
unknown about how this has affected its genetic attributes. Here we examined the factors that
contributed to shaping the current genetic constitution of Ae. albopictus in the Iberian Peninsula,
where the species was first found in 2004, by combining population genetics and Bayesian modelling.
We found that both mitochondrial and nuclear DNA markers showed a lack of genetic structure and
the presence of worldwide dominant haplotypes, suggesting regular introductions from abroad.
Mitochondrial DNA showed little genetic diversity compared to nuclear DNA, likely explained by
infection with maternally transmitted bacteria of the genus Wolbachia. Multilevel models revealed
that greater mosquito fluxes (estimated from commuting patterns and tiger mosquito population
distribution) and spatial proximity between sampling sites were associated with lower nuclear genetic
distance, suggesting that rapid short- and medium-distance dispersal is facilitated by humans through
vehicular traffic. This study highlights the significant role of human transportation in shaping the
genetic attributes of Ae. albopictus and promoting regional gene flow, and underscores the need for a
territorially integrated surveillance across scales of this disease-carrying mosquito.The research leading to these results has received funding from the Spanish
Ministry of Economy and Competitiveness (MINECO, Plan Estatal I+D+I CGL2013-43139-R), “la Caixa”
Foundation (ID 100010434) under agreement HR18-00336, and the European Research Council (ERC) under
the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 853271).Peer reviewe
A fast and inexpensive genotyping system for the simultaneous analysis of human and Aedes albopictus short tandem repeats
Abstract
Background: Determination of the interactions between hematophagous mosquitoes and their human hosts is of great importance for better understanding the transmission dynamics of mosquito-borne arboviruses and developing effective strategies to mitigate risk. Genetic analysis of human and mosquito DNA can play a key role in this but commercial kits for human short tandem repeat (STR) genotyping are expensive and do not allow for the simultaneous STR analysis of host and vector DNA. Here, we present an inexpensive and straightforward STR-loci multiplex system capable of simultaneously amplifying Ae. albopictus and human STRs from blood-fed mosquitoes. Additionally, we examine the effect of storage methods and post-feeding time on the integrity of host DNA.
Methods: Thirty-five STRs (16 human and 19 Ae. albopictus STRs) subdivided in three multiplexes were tested for amplification and scoring reliability. Under laboratory conditions we compared the efficacy of two preservation methods (absolute ethanol vs. lysis buffer) on the integrity of host DNA in Ae. albopictus blood meals. Furthermore, we evaluated the effect of post-feeding time by sacrificing blood-fed mosquitoes at different time intervals after feeding, and we assessed our ability to detect multiple feedings. To determine if the system can be employed successfully under field conditions, we carried out a preliminary study using field-collected Ae. albopictus.
Results: All 35 STRs amplified consistently in the laboratory. Lysis buffer performed better than absolute ethanol in terms of allele peak height and clarity of electropherograms. Complete human DNA profiles could be obtained up to 48h following the blood meal. Analysis of multiple feedings confirmed that peak heights can be used as a proxy to determine post-feeding time and thus derive the number of different people bitten by a mosquito. In the field trial, amplification was successful for 32 STRs. We found human DNA signal in 38 of the 61 field-collected mosquitoes (62%), of which 34 (89%) had ingested a single blood meal, while 4 (11%) contained double meals.
Conclusions: Our new genotyping system allows fast and reliable screening of both host and vector species, and can be further adapted to other mosquito species living in close contact with humans
Estat de conservació del cavilat (Cottus hispaniolensis) a la Val d’Aran
E. Carrillo, J. Ninot, T. Buchaca and M. Ventura. Blanes, LIFE+ LIMNOPIRINEUS Technical OfficeEl cavilat (Cottus hispaniolensis) és un dels peixos continentals
més amenaçats de Catalunya i Espanya. La seva
situació a la Val d’Aran va empitjorar dràsticament arran
de les riuades del 2013, fins al punt d’arribar pràcticament
a desaparèixer. Des d’aleshores, les poblacions s’han anat
recuperant progressivament, amb un lent increment de la
seva densitat mitjana i de les localitats ocupades. En part,
aquesta recuperació s’ha produït gràcies a actuacions emmarcades
en el projecte LIFE+ LimnoPirineus, que s’han
dissenyat específicament per a la recuperació d’aquesta
espècie dins l’espai de la xarxa Natura 2000 «Aigüestortes
» (ES0000022).Peer reviewe
A fast and inexpensive genotyping system for the simultaneous analysis of human and Aedes albopictus short tandem repeats
Background. Determination of the interactions between hematophagous mosquitoes and their human hosts is of great importance for better understanding the transmission dynamics of mosquito-borne arboviruses and developing effective strategies to mitigate risk. Genetic analysis of human and mosquito DNA can play a key role in this, but commercial kits for human short tandem repeat (STR) genotyping are expensive and do not allow for the simultaneous STR analysis of host and vector DNA. Here, we present an inexpensive and straightforward STR-loci multiplex system capable of simultaneously amplifying Aedes albopictus and human STRs from blood-fed mosquitoes. Additionally, we examine the effect of storage methods and post-feeding time on the integrity of host DNA. Methods. Thirty-five STRs (16 human and 19 Ae. albopictus STRs) subdivided in three multiplexes were tested for amplification and scoring reliability. Under laboratory conditions we compared the efficacy of two preservation methods (absolute ethanol vs lysis buffer) on the integrity of host DNA in Ae. albopictus blood meals. We also evaluated the effect of post-feeding time by sacrificing blood-fed mosquitoes at different time intervals after feeding, and we assessed our ability to detect multiple feedings. To determine if the system can be employed successfully under field conditions, we carried out a preliminary study using field-collected Ae. albopictus. Results. All 35 STRs amplified consistently in the laboratory. Lysis buffer performed better than absolute ethanol in terms of allele peak height and clarity of electropherograms. Complete human DNA profiles could be obtained up to 48 h following the blood meal. Analysis of multiple feedings confirmed that peak heights can be used as a proxy to determine post-feeding time and thus derive the number of different people bitten by a mosquito. In the field trial, amplification was successful for 32 STRs. We found human DNA signal in 38 of the 61 field-collected mosquitoes (62%), of which 34 (89%) had ingested a single blood meal, while four (11%) contained double meals. Conclusions. Our new genotyping system allows fast and reliable screening of both host and vector species, and can be further adapted to other mosquito species living in close contact with humans.This work was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 853271)
Estado de conservación del cavilat (Cottus hispaniolensis) en el valle de Arán
E. Carrillo, J. Ninot, T. Buchaca and M. Ventura. Blanes, LIFE+ LIMNOPIRINEUS Technical OfficeEl cavilat (Cottus hispaniolensis) es uno de los peces continentales
más amenazados de Cataluña y España. Su situación
en el valle de Arán empeoró drásticamente a raíz
de las riadas del 2013, hasta el punto de llegar a su práctica
desaparición. Desde entonces, sus poblaciones se han
ido recuperando progresivamente, con un lento incremento
de su densidad media y de las localidades ocupadas.
En parte, esta recuperación se ha producido gracias a
actuaciones enmarcadas dentro del proyecto LIFE+ LimnoPirineus,
que se han diseñado específicamente para la
recuperación de esta especie dentro del espacio de Red
Natura 2000 de Aigüestortes (ES0000022).Peer reviewe
Conservation status of the pyrenean sculpin (cottus hispaniolensis) in the Aran Valley
E. Carrillo, J. Ninot, T. Buchaca and M. Ventura. Blanes, LIFE+ LIMNOPIRINEUS Technical OfficeThe Pyrenean sculpin (Cottus hispaniolensis) is one of the
most threatened freshwater fish in Catalonia and Spain.
Its status in the Aran Valley drastically deteriorated as a
result of the floods of 2013, to the point of reaching its
practical disappearance. Since then, their populations
have been progressively recovering, with a slow increase
in their average density and occupied localities. In part,
this recovery has been produced thanks to actions framed
within the LIFE+ LimnoPirineus project, which have
been specifically designed for the recovery of this species
within the Natura 2000 network space “Aigüestortes”
(ES0000022).Peer reviewe
New insights on patterns of genetic admixture and phylogeographic history in Iberian high mountain populations of midwife toads
Este artículo contiene 25 páginas, 7 figuras, 1 tabla.Multiple Quaternary glacial refugia in the Iberian Peninsula, commonly known as “refugia
within refugia”, allowed diverging populations to come into contact and admix, potentially
boosting substantial mito-nuclear discordances. In this study, we employ a comprehensive
set of mitochondrial and nuclear markers to shed light onto the drivers of geographical differentiation
in Iberian high mountain populations of the midwife toads Alytes obstetricans and
A. almogavarii from the Pyrenees, Picos de Europa and Guadarrama Mountains. In the
three analysed mountain regions, we detected evidence of extensive mito-nuclear discordances
and/or admixture between taxa. Clustering analyses identified three major divergent
lineages in the Pyrenees (corresponding to the eastern, central and central-western Pyrenees),
which possibly recurrently expanded and admixed during the succession of glacialinterglacial
periods that characterised the Late Pleistocene, and that currently follow a ringshaped
diversification pattern. On the other hand, populations from the Picos de Europa
mountains (NW Iberian Peninsula) showed a mitochondrial affinity to central-western Pyrenean
populations and a nuclear affinity to populations from the central Iberian Peninsula,
suggesting a likely admixed origin for Picos de Europa populations. Finally, populations
from the Guadarrama Mountain Range (central Iberian Peninsula) were depleted of genetic
diversity, possibly as a consequence of a recent epidemic of chytridiomycosis. This work
highlights the complex evolutionary history that shaped the current genetic composition of
high mountain populations, and underscores the importance of using a multilocus approach
to better infer the dynamics of population divergence.This work was supported by the
European Commission projects LIFE+
LIMNOPIRINEUS (LIFE13 NAT/ES/001210, PI: M.
V.), LIFE RESQUE ALPYR (LIFE20 NAT/ES/00347,
PI: M.V.) and Biodiversa FISHME (BiodivRestor-
280, PI: M.V.) and by the Spanish Government
projects FUNBIO (RTI2018-096217-B-I00, PI: M.
V.), BIOOCULT (2413/2017, PI: M.V.), (Organismo
Auto´nomo Parques Nacionales 2399/2017; PI: J.B)
and Picos de Europa National Park grants for 2015
and 2016 (PI: J.B.). F.L. had a doctoral grant
funded by Fundac¸ão para a Ciência e a Tecnologia
(FCT, grant number PD/BD/52598/2014). M.J.J.
had an International collaboration grant (National
Institute of Ecology) and a postdoctoral grant
funded by FCT (grant number SFRH/BPD/109148/
2015).Peer reviewe
Additional file 1 of A fast and inexpensive genotyping system for the simultaneous analysis of human and Aedes albopictus short tandem repeats
Additional file 1: Figure S1. Map of the study area. Main map shows the Iberian Peninsula, with the Blanes study site marked just above Barcelona. Made with Natural Earth, free vector and raster map data from Natural Earth ( https://www.naturalearthdata.com ). Inset map shows orthophoto of Blanes, with the Marimurtra Botanical Garden field site marked in yellow and the CEAB laboratory marked in blue. Map derived from the Orthophoto of Catalonia 1:5.000 of the Institut Cartogràfic i Geològic de Catalunya (ICGC), used under a CC BY 4.0 license