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1.
Invertebr Syst ; 382024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38744526

RESUMEN

Despite discovery more than 100years ago and documented global occurrence from shallow waters to the deep sea, the life cycle of the enigmatic crustacean y-larvae isincompletely understood and adult forms remain unknown. To date, only 2 of the 17 formally described species, all based on larval stages, have been investigated using an integrative taxonomic approach. This approach provided descriptions of the morphology of the naupliar and cyprid stages, and made use of exuvial voucher material and DNA barcodes. To improve our knowledge about the evolutionary history and ecological importance of y-larvae, we developed a novel protocol that maximises the amount of morpho-ecological and molecular data that can be harvested from single larval specimens. This includes single-specimen DNA barcoding and daily imaging of y-nauplii reared in culture dishes, mounting of the last naupliar exuviae on a slide as a reference voucher, live imaging of the y-cyprid instar that follows, and fixation, DNA extraction, amplification and sequencing of the y-cyprid specimen. Through development and testing of a suite of new primers for both nuclear and mitochondrial protein-coding and ribosomal genes, we showcase how new sequence data can be used to estimate the phylogeny of Facetotecta. We expect that our novel procedure will help to unravel the complex systematics of y-larvae and show how these fascinating larval forms have evolved. Moreover, we posit that our protocols should work on larval specimens from a diverse array of moulting marine invertebrate taxa.


Asunto(s)
Código de Barras del ADN Taxonómico , Larva , Animales , Código de Barras del ADN Taxonómico/métodos , Larva/genética , Larva/anatomía & histología , Larva/crecimiento & desarrollo , Crustáceos/genética , Crustáceos/clasificación , Crustáceos/anatomía & histología , Especificidad de la Especie , Filogenia
2.
Parasit Vectors ; 17(1): 216, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734639

RESUMEN

BACKGROUND: Mosquitoes pose a risk to human health worldwide, and correct species identification and detection of cryptic species are the most important keys for surveillance and control of mosquito vectors. In addition to traditional identification based on morphology, DNA barcoding has recently been widely used as a complementary tool for reliable identification of mosquito species. The main objective of this study was to create a reference DNA barcode library for the Croatian mosquito fauna, which should contribute to more accurate and faster identification of species, including cryptic species, and recognition of relevant vector species. METHODS: Sampling was carried out in three biogeographical regions of Croatia over six years (2017-2022). The mosquitoes were morphologically identified; molecular identification was based on the standard barcoding region of the mitochondrial COI gene and the nuclear ITS2 region, the latter to identify species within the Anopheles maculipennis complex. The BIN-RESL algorithm assigned the COI sequences to the corresponding BINs (Barcode Index Number clusters) in BOLD, i.e. to putative MOTUs (Molecular Operational Taxonomic Units). The bPTP and ASAP species delimitation methods were applied to the genus datasets in order to verify/confirm the assignment of specimens to specific MOTUs. RESULTS: A total of 405 mosquito specimens belonging to six genera and 30 morphospecies were collected and processed. Species delimitation methods assigned the samples to 31 (BIN-RESL), 30 (bPTP) and 28 (ASAP) MOTUs, with most delimited MOTUs matching the morphological identification. Some species of the genera Culex, Aedes and Anopheles were assigned to the same MOTUs, especially species that are difficult to distinguish morphologically and/or represent species complexes. In total, COI barcode sequences for 34 mosquito species and ITS2 sequences for three species of the genus Anopheles were added to the mosquito sequence database for Croatia, including one individual from the Intrudens Group, which represents a new record for the Croatian mosquito fauna. CONCLUSION: We present the results of the first comprehensive study combining morphological and molecular identification of most mosquito species present in Croatia, including several invasive and vector species. With the exception of some closely related species, this study confirmed that DNA barcoding based on COI provides a reliable basis for the identification of mosquito species in Croatia.


Asunto(s)
Culicidae , Código de Barras del ADN Taxonómico , Complejo IV de Transporte de Electrones , Mosquitos Vectores , Animales , Croacia , Mosquitos Vectores/genética , Mosquitos Vectores/clasificación , Mosquitos Vectores/anatomía & histología , Culicidae/clasificación , Culicidae/genética , Complejo IV de Transporte de Electrones/genética , Anopheles/genética , Anopheles/clasificación , Filogenia , Biblioteca de Genes
3.
PLoS One ; 19(5): e0301605, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38739592

RESUMEN

Oxygen minimum zones (OMZ) represent ~8% of the ocean, with the Pacific as the largest and top expanding area. These regions influence marine ecosystems, promoting anaerobic microbial communities. Nevertheless, only a fraction of microbial diversity has been studied, with fungi being the less explored component. So, herein we analyzed fungal diversity patterns in surface and subsurface sediments along a bathymetric transect using metabarcoding of the ITS1 region in the OMZ of the Mexican Pacific off Mazatlán. We identified 353 amplicon sequence variants (ASV), within the Ascomycota, Basidiomycota, and Rozellomycota. Spatial patterns evidenced higher alpha diversity in nearshore and subsurface subsamples, probably due to temporal fluctuations in organic matter inputs. Small-scale heterogeneity characterized the community with the majority of ASV (269 ASV) occurring in a single subsample, hinting at the influence of local biogeochemical conditions. This baseline data evidenced a remarkable fungal diversity presenting high variation along a bathymetric and vertical transects.


Asunto(s)
Biodiversidad , Código de Barras del ADN Taxonómico , Hongos , Sedimentos Geológicos , Oxígeno , Sedimentos Geológicos/microbiología , Oxígeno/metabolismo , Oxígeno/análisis , Hongos/genética , Hongos/clasificación , Hongos/aislamiento & purificación , Océano Pacífico , Filogenia
4.
Mol Biol Rep ; 51(1): 639, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38727924

RESUMEN

BACKGROUND: Peucedani Radix, also known as "Qian-hu" is a traditional Chinese medicine derived from Peucedanum praeruptorum Dunn. It is widely utilized for treating wind-heat colds and coughs accompanied by excessive phlegm. However, due to morphological similarities, limited resources, and heightened market demand, numerous substitutes and adulterants of Peucedani Radix have emerged within the herbal medicine market. Moreover, Peucedani Radix is typically dried and sliced for sale, rendering traditional identification methods challenging. MATERIALS AND METHODS: We initially examined and compared 104 commercial "Qian-hu" samples from various Chinese medicinal markets and 44 species representing genuine, adulterants or substitutes, utilizing the mini barcode ITS2 region to elucidate the botanical origins of the commercial "Qian-hu". The nucleotide signature specific to Peucedani Radix was subsequently developed by analyzing the polymorphic sites within the aligned ITS2 sequences. RESULTS: The results demonstrated a success rate of 100% and 93.3% for DNA extraction and PCR amplification, respectively. Forty-five samples were authentic "Qian-hu", while the remaining samples were all adulterants, originating from nine distinct species. Peucedani Radix, its substitutes, and adulterants were successfully identified based on the neighbor-joining tree. The 24-bp nucleotide signature (5'-ATTGTCGTACGAATCCTCGTCGTC-3') revealed distinct differences between Peucedani Radix and its common substitutes and adulterants. The newly designed specific primers (PR-F/PR-R) can amplify the nucleotide signature region from commercial samples and processed materials with severe DNA degradation. CONCLUSIONS: We advocate for the utilization of ITS2 and nucleotide signature for the rapid and precise identification of herbal medicines and their adulterants to regulate the Chinese herbal medicine industry.


Asunto(s)
Código de Barras del ADN Taxonómico , ADN de Plantas , ADN de Plantas/genética , Código de Barras del ADN Taxonómico/métodos , Medicamentos Herbarios Chinos/normas , Apiaceae/genética , Apiaceae/clasificación , Medicina Tradicional China/normas , ADN Espaciador Ribosómico/genética , Contaminación de Medicamentos , Plantas Medicinales/genética , Filogenia , Análisis de Secuencia de ADN/métodos , Reacción en Cadena de la Polimerasa/métodos , Nucleótidos/genética , Nucleótidos/análisis
5.
BMC Ecol Evol ; 24(1): 67, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773413

RESUMEN

BACKGROUND: The ecology and biology of oysters (Ostreidae) across the tropics is poorly understood. Morphological plasticity and shared characteristics among oysters have resulted in the misidentification of species, creating challenges for understanding basic species-specific biological information that is required for restoration and aquaculture. Genetic barcoding has proven essential for accurate species identification and understanding species geographic ranges. To reduce the costs of molecular species identification we developed multiplex assays using the cytochrome c oxidase subunit I (COI or cox1) barcoding gene for the rapid identification of five species of oysters within the genus Saccostrea that are commonly found in Queensland, Australia: Saccostrea glomerata, Saccostrea lineage B, Saccostrea lineage F, Saccostrea lineage G, and Saccostrea spathulata (lineage J). RESULTS: Multiplex assays were successful in species-specific amplification of targeted species. The practical application of these primers was tested on wild spat collected from a pilot restoration project in Moreton Bay, Queensland, with identified species (S. glomerata, lineage B and lineage G) validated by Sanger sequencing. DNA sampling by extraction of oyster pallial fluid was also tested on adult oysters collected from the Noosa estuary in Queensland to assess whether oysters were able to be identified non-destructively. DNA concentrations as low as 1 ng/ µL still amplified in most cases, allowing for identification, and mortality at 6 weeks post pallial fluid collection was low (3 out of 104 sampled oysters). CONCLUSION: These multiplex assays will be essential tools for species identification in future studies, and we successfully demonstrate their practical application in both restoration and aquaculture contexts in Queensland. The multiplex assays developed in this study outline easily replicable methods for the development of additional species-specific primer sets for the rapid identification of other species of Saccostrea found across the Indo-Pacific, which will be instrumental in unravelling the taxonomic ambiguities within this genus in tropical regions.


Asunto(s)
Acuicultura , Código de Barras del ADN Taxonómico , Complejo IV de Transporte de Electrones , Reacción en Cadena de la Polimerasa Multiplex , Ostreidae , Animales , Reacción en Cadena de la Polimerasa Multiplex/métodos , Acuicultura/métodos , Código de Barras del ADN Taxonómico/métodos , Complejo IV de Transporte de Electrones/genética , Ostreidae/genética , Queensland , Especificidad de la Especie , Conservación de los Recursos Naturales/métodos
6.
Environ Int ; 187: 108706, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38696978

RESUMEN

Environmental DNA (eDNA) technology has revolutionized biomonitoring, but challenges remain regarding water sample processing. The passive eDNA sampler (PEDS) represents a viable alternative to active, water filtration-based eDNA enrichment methods, but the effectiveness of PEDS for surveying biodiverse and complex natural water bodies is unknown. Here, we collected eDNA using filtration and glass fiber filter-based PEDS (submerged in water for 1 d) from 27 sites along the final reach of the Yangtze River and the coast of the Yellow Sea, followed by eDNA metabarcoding analysis of fish biodiversity and quantitative PCR (qPCR) for a critically endangered aquatic mammal, the Yangtze finless porpoise. We ultimately detected 98 fish species via eDNA metabarcoding. Both eDNA sampling methods captured comparable local species richness and revealed largely similar spatial variation in fish assemblages and community partitions between the river and sea sites. Notably, the Yangtze finless porpoise was detected only in the metabarcoding of eDNA collected by PEDS at five sites. Also, species-specific qPCR revealed that the PEDS captured porpoise eDNA at more sites (7 vs. 2), in greater quantities, and with a higher detection probability (0.803 vs. 0.407) than did filtration. Our results demonstrate the capacity of PEDS for surveying fish biodiversity, and support that continuous eDNA collection by PEDS can be more effective than instantaneous water sampling at capturing low abundance and ephemeral species in natural waters. Thus, the PEDS approach can facilitate more efficient and convenient eDNA-based biodiversity surveillance and rare species detection.


Asunto(s)
Biodiversidad , ADN Ambiental , Monitoreo del Ambiente , Peces , Animales , ADN Ambiental/análisis , Monitoreo del Ambiente/métodos , Peces/genética , Ríos/química , Código de Barras del ADN Taxonómico/métodos , Marsopas/genética , China
7.
Parasitol Res ; 123(5): 201, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38698272

RESUMEN

Gastrointestinal nematodes (GINs) are a common threat faced by pastoral livestock. Since their major introduction to the UK in the early 1990s, South American camelids have been cograzed with sheep, horses, and other livestock, allowing exposure to a range of GIN species. However, there have been no molecular-based studies to investigate the GIN populations present in these camelids. In the current study, we sampled nine alpaca herds from northern England and southern Scotland and used high-throughput metabarcoded sequencing to describe their GIN species composition. A total of 71 amplicon sequence variants (ASVs) were identified representing eight known GIN species. Haemonchus contortus was the most prevalent species found in almost all herds in significant proportions. The identification of H. contortus in other livestock species is unusual in the northern UK, implying that alpacas may be suitable hosts and potential reservoirs for infection in other hosts. In addition, the camelid-adapted GIN species Camelostrongylus mentulatus was identified predominantly in herds with higher faecal egg counts. These findings highlight the value of applying advanced molecular methods, such as nemabiome metabarcoding to describe the dynamics of gastrointestinal nematode infections in novel situations. The results provide a strong base for further studies involving cograzing animals to confirm the potential role of alpacas in transmitting GIN species between hosts.


Asunto(s)
Camélidos del Nuevo Mundo , Hemoncosis , Haemonchus , Animales , Camélidos del Nuevo Mundo/parasitología , Haemonchus/genética , Haemonchus/clasificación , Haemonchus/aislamiento & purificación , Prevalencia , Hemoncosis/veterinaria , Hemoncosis/parasitología , Hemoncosis/epidemiología , Código de Barras del ADN Taxonómico , Reino Unido/epidemiología , Infecciones por Strongylida/veterinaria , Infecciones por Strongylida/parasitología , Infecciones por Strongylida/epidemiología , Heces/parasitología , Inglaterra/epidemiología , Escocia/epidemiología
8.
Philos Trans R Soc Lond B Biol Sci ; 379(1904): 20230123, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38705177

RESUMEN

Arthropods contribute importantly to ecosystem functioning but remain understudied. This undermines the validity of conservation decisions. Modern methods are now making arthropods easier to study, since arthropods can be mass-trapped, mass-identified, and semi-mass-quantified into 'many-row (observation), many-column (species)' datasets, with homogeneous error, high resolution, and copious environmental-covariate information. These 'novel community datasets' let us efficiently generate information on arthropod species distributions, conservation values, uncertainty, and the magnitude and direction of human impacts. We use a DNA-based method (barcode mapping) to produce an arthropod-community dataset from 121 Malaise-trap samples, and combine it with 29 remote-imagery layers using a deep neural net in a joint species distribution model. With this approach, we generate distribution maps for 76 arthropod species across a 225 km2 temperate-zone forested landscape. We combine the maps to visualize the fine-scale spatial distributions of species richness, community composition, and site irreplaceability. Old-growth forests show distinct community composition and higher species richness, and stream courses have the highest site-irreplaceability values. With this 'sideways biodiversity modelling' method, we demonstrate the feasibility of biodiversity mapping at sufficient spatial resolution to inform local management choices, while also being efficient enough to scale up to thousands of square kilometres. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.


Asunto(s)
Artrópodos , Biodiversidad , ADN Ambiental , Tecnología de Sensores Remotos , Artrópodos/clasificación , Animales , ADN Ambiental/análisis , Tecnología de Sensores Remotos/métodos , Bosques , Distribución Animal , Código de Barras del ADN Taxonómico/métodos
9.
Philos Trans R Soc Lond B Biol Sci ; 379(1904): 20230124, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38705180

RESUMEN

DNA-based identification is vital for classifying biological specimens, yet methods to quantify the uncertainty of sequence-based taxonomic assignments are scarce. Challenges arise from noisy reference databases, including mislabelled entries and missing taxa. PROTAX addresses these issues with a probabilistic approach to taxonomic classification, advancing on methods that rely solely on sequence similarity. It provides calibrated probabilistic assignments to a partially populated taxonomic hierarchy, accounting for taxa that lack references and incorrect taxonomic annotation. While effective on smaller scales, global application of PROTAX necessitates substantially larger reference libraries, a goal previously hindered by computational barriers. We introduce PROTAX-GPU, a scalable algorithm capable of leveraging the global Barcode of Life Data System (>14 million specimens) as a reference database. Using graphics processing units (GPU) to accelerate similarity and nearest-neighbour operations and the JAX library for Python integration, we achieve over a 1000 × speedup compared with the central processing unit (CPU)-based implementation without compromising PROTAX's key benefits. PROTAX-GPU marks a significant stride towards real-time DNA barcoding, enabling quicker and more efficient species identification in environmental assessments. This capability opens up new avenues for real-time monitoring and analysis of biodiversity, advancing our ability to understand and respond to ecological dynamics. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.


Asunto(s)
Algoritmos , Código de Barras del ADN Taxonómico , Código de Barras del ADN Taxonómico/métodos , Clasificación/métodos , Gráficos por Computador , Animales
10.
Philos Trans R Soc Lond B Biol Sci ; 379(1904): 20230120, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38705187

RESUMEN

Holistic insect monitoring needs scalable techniques to overcome taxon biases, determine species abundances, and gather functional traits for all species. This requires that we address taxonomic impediments and the paucity of data on abundance, biomass and functional traits. We here outline how these data deficiencies could be addressed at scale. The workflow starts with large-scale barcoding (megabarcoding) of all specimens from mass samples obtained at biomonitoring sites. The barcodes are then used to group the specimens into molecular operational taxonomic units that are subsequently tested/validated as species with a second data source (e.g. morphology). New species are described using barcodes, images and short diagnoses, and abundance data are collected for both new and described species. The specimen images used for species discovery then become the raw material for training artificial intelligence identification algorithms and collecting trait data such as body size, biomass and feeding modes. Additional trait data can be obtained from vouchers by using genomic tools developed by molecular ecologists. Applying this pipeline to a few samples per site will lead to greatly improved insect monitoring regardless of whether the species composition of a sample is determined with images, metabarcoding or megabarcoding. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.


Asunto(s)
Código de Barras del ADN Taxonómico , Insectos , Insectos/fisiología , Insectos/clasificación , Insectos/genética , Animales , Código de Barras del ADN Taxonómico/métodos , Biodiversidad
11.
Philos Trans R Soc Lond B Biol Sci ; 379(1904): 20230118, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38705189

RESUMEN

Molecular methods are currently some of the best-suited technologies for implementation in insect monitoring. However, the field is developing rapidly and lacks agreement on methodology or community standards. To apply DNA-based methods in large-scale monitoring, and to gain insight across commensurate data, we need easy-to-implement standards that improve data comparability. Here, we provide three recommendations for how to improve and harmonize efforts in biodiversity assessment and monitoring via metabarcoding: (i) we should adopt the use of synthetic spike-ins, which will act as positive controls and internal standards; (ii) we should consider using several markers through a multiplex polymerase chain reaction (PCR) approach; and (iii) we should commit to the publication and transparency of all protocol-associated metadata in a standardized fashion. For (i), we provide a ready-to-use recipe for synthetic cytochrome c oxidase spike-ins, which enable between-sample comparisons. For (ii), we propose two gene regions for the implementation of multiplex PCR approaches, thereby achieving a more comprehensive community description. For (iii), we offer guidelines for transparent and unified reporting of field, wet-laboratory and dry-laboratory procedures, as a key to making comparisons between studies. Together, we feel that these three advances will result in joint quality and calibration standards rather than the current laboratory-specific proof of concepts. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.


Asunto(s)
Biodiversidad , Código de Barras del ADN Taxonómico , Insectos , Animales , Código de Barras del ADN Taxonómico/métodos , Código de Barras del ADN Taxonómico/normas , Insectos/genética , Reacción en Cadena de la Polimerasa Multiplex/métodos , Reacción en Cadena de la Polimerasa Multiplex/normas
12.
Sci Rep ; 14(1): 10154, 2024 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698067

RESUMEN

In the face of global ecosystem changes driven by anthropogenic activities, effective biomonitoring strategies are crucial for mitigating impacts on vulnerable aquatic habitats. Time series analysis underscores a great significance in understanding the dynamic nature of marine ecosystems, especially amidst climate change disrupting established seasonal patterns. Focusing on Norway's Oslo fjord, our research utilises eDNA-based monitoring for temporal analysis of aquatic biodiversity during a one year period, with bi-monthly sampling along a transect. To increase the robustness of the study, a taxonomic assignment comparing BLAST+ and SINTAX approaches was done. Utilising MiFish and Elas02 primer sets, our study detected 63 unique fish species, including several commercially important species. Our findings reveal a substantial increase in read abundance during specific migratory cycles, highlighting the efficacy of eDNA metabarcoding for fish composition characterization. Seasonal dynamics for certain species exhibit clear patterns, emphasising the method's utility in unravelling ecological complexities. eDNA metabarcoding emerges as a cost-effective tool with considerable potential for fish community monitoring for conservation purposes in dynamic marine environments like the Oslo fjord, contributing valuable insights for informed management strategies.


Asunto(s)
Biodiversidad , Código de Barras del ADN Taxonómico , Estuarios , Peces , Estaciones del Año , Animales , Peces/genética , Peces/clasificación , Noruega , Código de Barras del ADN Taxonómico/métodos , Ecosistema , Monitoreo del Ambiente/métodos , ADN Ambiental/genética , ADN Ambiental/análisis
13.
PeerJ ; 12: e17091, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38708339

RESUMEN

Monitoring the diversity and distribution of species in an ecosystem is essential to assess the success of restoration strategies. Implementing biomonitoring methods, which provide a comprehensive assessment of species diversity and mitigate biases in data collection, holds significant importance in biodiversity research. Additionally, ensuring that these methods are cost-efficient and require minimal effort is crucial for effective environmental monitoring. In this study we compare the efficiency of species detection, the cost and the effort of two non-destructive sampling techniques: Baited Remote Underwater Video (BRUV) and environmental DNA (eDNA) metabarcoding to survey marine vertebrate species. Comparisons were conducted along the Sussex coast upon the introduction of the Nearshore Trawling Byelaw. This Byelaw aims to boost the recovery of the dense kelp beds and the associated biodiversity that existed in the 1980s. We show that overall BRUV surveys are more affordable than eDNA, however, eDNA detects almost three times as many species as BRUV. eDNA and BRUV surveys are comparable in terms of effort required for each method, unless eDNA analysis is carried out externally, in which case eDNA requires less effort for the lead researchers. Furthermore, we show that increased eDNA replication yields more informative results on community structure. We found that using both methods in conjunction provides a more complete view of biodiversity, with BRUV data supplementing eDNA monitoring by recording species missed by eDNA and by providing additional environmental and life history metrics. The results from this study will serve as a baseline of the marine vertebrate community in Sussex Bay allowing future biodiversity monitoring research projects to understand community structure as the ecosystem recovers following the removal of trawling fishing pressure. Although this study was regional, the findings presented herein have relevance to marine biodiversity and conservation monitoring programs around the globe.


Asunto(s)
Biodiversidad , ADN Ambiental , Monitoreo del Ambiente , ADN Ambiental/análisis , ADN Ambiental/genética , Animales , Monitoreo del Ambiente/métodos , Organismos Acuáticos/genética , Grabación en Video/métodos , Ecosistema , Código de Barras del ADN Taxonómico/métodos
14.
Nat Cell Biol ; 26(5): 710-718, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38714853

RESUMEN

During brain development, neural progenitors expand through symmetric divisions before giving rise to differentiating cell types via asymmetric divisions. Transition between those modes varies among individual neural stem cells, resulting in clones of different sizes. Imaging-based lineage tracing allows for lineage analysis at high cellular resolution but systematic approaches to analyse clonal behaviour of entire tissues are currently lacking. Here we implement whole-tissue lineage tracing by genomic DNA barcoding in 3D human cerebral organoids, to show that individual stem cell clones produce progeny on a vastly variable scale. By using stochastic modelling we find that variable lineage sizes arise because a subpopulation of lineages retains symmetrically dividing cells. We show that lineage sizes can adjust to tissue demands after growth perturbation via chemical ablation or genetic restriction of a subset of cells in chimeric organoids. Our data suggest that adaptive plasticity of stem cell populations ensures robustness of development in human brain organoids.


Asunto(s)
Linaje de la Célula , Células-Madre Neurales , Organoides , Organoides/citología , Organoides/metabolismo , Humanos , Células-Madre Neurales/metabolismo , Células-Madre Neurales/citología , Encéfalo/citología , Encéfalo/crecimiento & desarrollo , Encéfalo/metabolismo , Diferenciación Celular , Proliferación Celular , Células Clonales , Neurogénesis/genética , Código de Barras del ADN Taxonómico , Animales
15.
Nat Commun ; 15(1): 4234, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762544

RESUMEN

Interactions between genetic perturbations and segregating loci can cause perturbations to show different phenotypic effects across genetically distinct individuals. To study these interactions on a genome scale in many individuals, we used combinatorial DNA barcode sequencing to measure the fitness effects of 8046 CRISPRi perturbations targeting 1721 distinct genes in 169 yeast cross progeny (or segregants). We identified 460 genes whose perturbation has different effects across segregants. Several factors caused perturbations to show variable effects, including baseline segregant fitness, the mean effect of a perturbation across segregants, and interacting loci. We mapped 234 interacting loci and found four hub loci that interact with many different perturbations. Perturbations that interact with a given hub exhibit similar epistatic relationships with the hub and show enrichment for cellular processes that may mediate these interactions. These results suggest that an individual's response to perturbations is shaped by a network of perturbation-locus interactions that cannot be measured by approaches that examine perturbations or natural variation alone.


Asunto(s)
Epistasis Genética , Genoma Fúngico , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Variación Genética , Aptitud Genética , Sistemas CRISPR-Cas , Fenotipo , Código de Barras del ADN Taxonómico
16.
PLoS One ; 19(4): e0301197, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38557776

RESUMEN

Dams and weirs impede the continuity of rivers and transit of migratory fish. To overcome this obstacle, fishways are installed worldwide; however, management after installation is important. The Miyanaka Intake Dam has three fish ladders with different flow velocities and discharges and has been under adaptive management since 2012. Fish catch surveys, conducted as an adaptive management strategy, place a heavy burden on fish. Furthermore, a large number of investigators must be mobilized during the 30-day investigation period. Thus, a monitoring method using environmental DNA that exerts no burden on fish and requires only a few surveyors (to obtain water samples) and an in-house analyst was devised; however, its implementation in a fishway away from the point of analysis and with limited flow space and its effective water sampling frequency have not been reported. Therefore, in 2019, we started a trial aiming to evaluate the methods and application conditions of environmental DNA surveys for the continuous and long-term monitoring of various fish fauna upstream and downstream of the Miyanaka Intake Dam. To evaluate the fish fauna, the results of an environmental DNA survey (metabarcoding method) for 2019 to 2022 were compared to those of a catch survey in the fishway from 2012 to 2022. The results confirmed the use of environmental DNA surveys in evaluating the contribution of fishways to biodiversity under certain conditions and introduced a novel method for sample collection.


Asunto(s)
ADN Ambiental , Animales , Peces/genética , Biodiversidad , Ríos , Agua , Monitoreo del Ambiente/métodos , Código de Barras del ADN Taxonómico/métodos , Ecosistema
17.
Parasit Vectors ; 17(1): 171, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566239

RESUMEN

BACKGROUND: Identification of mosquitoes greatly relies on morphological specification. Since some species cannot be distinguished reliably by morphological methods, it is important to incorporate molecular techniques into the diagnostic pipeline. DNA barcoding using Sanger sequencing is currently widely used for identification of mosquito species. However, this method does not allow detection of multiple species in one sample, which would be important when analysing mosquito eggs. Detection of container breeding Aedes is typically performed by collecting eggs using ovitraps. These traps consist of a black container filled with water and a wooden spatula inserted for oviposition support. Aedes mosquitoes of different species might lay single or multiple eggs on the spatula. In contrast to Sanger sequencing of specific polymerase chain reaction (PCR) products, multiplex PCR protocols targeting specific species of interest can be of advantage for detection of multiple species in the same sample. METHODS: For this purpose, we adapted a previously published PCR protocol for simultaneous detection of four different Aedes species that are relevant for Austrian monitoring programmes, as they can be found in ovitraps: Aedes albopictus, Aedes japonicus, Aedes koreicus, and Aedes geniculatus. For evaluation of the multiplex PCR protocol, we analysed 2271 ovitrap mosquito samples from the years 2021 and 2022, which were collected within the scope of an Austrian nationwide monitoring programme. We compared the results of the multiplex PCR to the results of DNA barcoding. RESULTS: Of 2271 samples, the multiplex PCR could identify 1990 samples, while species determination using DNA barcoding of the mitochondrial cytochrome c oxidase subunit I gene was possible in 1722 samples. The multiplex PCR showed a mixture of different species in 47 samples, which could not be detected with DNA barcoding. CONCLUSIONS: In conclusion, identification of Aedes species in ovitrap samples was more successful when using the multiplex PCR protocol as opposed to the DNA barcoding protocol. Additionally, the multiplex PCR allowed us to detect multiple species in the same sample, while those species might have been missed when using DNA barcoding with Sanger sequencing alone. Therefore, we propose that the multiplex PCR protocol is highly suitable and of great advantage when analysing mosquito eggs from ovitraps.


Asunto(s)
Aedes , Código de Barras del ADN Taxonómico , Femenino , Animales , Reacción en Cadena de la Polimerasa Multiplex , Óvulo , Aedes/genética , Mosquitos Vectores/genética
18.
PLoS One ; 19(4): e0300811, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38568891

RESUMEN

Multi-locus genetic data for phylogeographic studies is generally limited in geographic and taxonomic scope as most studies only examine a few related species. The strong adoption of DNA barcoding has generated large datasets of mtDNA COI sequences. This work examines the butterfly fauna of Canada and United States based on 13,236 COI barcode records derived from 619 species. It compiles i) geographic maps depicting the spatial distribution of haplotypes, ii) haplotype networks (minimum spanning trees), and iii) standard indices of genetic diversity such as nucleotide diversity (π), haplotype richness (H), and a measure of spatial genetic structure (GST). High intraspecific genetic diversity and marked spatial structure were observed in the northwestern and southern North America, as well as in proximity to mountain chains. While species generally displayed concordance between genetic diversity and spatial structure, some revealed incongruence between these two metrics. Interestingly, most species falling in this category shared their barcode sequences with one at least other species. Aside from revealing large-scale phylogeographic patterns and shedding light on the processes underlying these patterns, this work also exposed cases of potential synonymy and hybridization.


Asunto(s)
Mariposas Diurnas , Animales , Estados Unidos , Mariposas Diurnas/genética , Filogeografía , ADN Mitocondrial/genética , ADN Mitocondrial/química , Mitocondrias/genética , Haplotipos , Variación Genética , Código de Barras del ADN Taxonómico , Filogenia
19.
PLoS One ; 19(4): e0300903, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38598453

RESUMEN

The order Hymenoptera holds great significance for humans, particularly in tropical and subtropical regions, due to its role as a pollinator of wild and cultivated flowering plants, parasites of destructive insects and honey producers. Despite this importance, limited attention has been given to the genetic diversity and molecular identification of Hymenopteran insects in most protected areas. This study provides insights into the first DNA barcode of Hymenopteran insects collected from Hazarganji Chiltan National Park (HCNP) and contributes to the global reference library of DNA barcodes. A total of 784 insect specimens were collected using Malaise traps, out of which 538 (68.62%) specimens were morphologically identified as Hymenopteran insects. The highest abundance of species of Hymenoptera (133/538, 24.72%) was observed during August and least in November (16/538, 2.97%). Genomic DNA extraction was performed individually from 90/538 (16.73%) morphologically identified specimens using the standard phenol-chloroform method, which were subjected separately to the PCR for their molecular confirmation via the amplification of cytochrome c oxidase subunit 1 (cox1) gene. The BLAST analyses of obtained sequences showed 91.64% to 100% identities with related sequences and clustered phylogenetically with their corresponding sequences that were reported from Australia, Bulgaria, Canada, Finland, Germany, India, Israel, and Pakistan. Additionally, total of 13 barcode index numbers (BINs) were assigned by Barcode of Life Data Systems (BOLD), out of which 12 were un-unique and one was unique (BOLD: AEU1239) which was assigned for Anthidium punctatum. This indicates the potential geographical variation of Hymenopteran population in HCNP. Further comprehensive studies are needed to molecularly confirm the existing insect species in HCNP and evaluate their impacts on the environment, both as beneficial (for example, pollination, honey producers and natural enemies) and detrimental (for example, venomous stings, crop damage, and pathogens transmission).


Asunto(s)
Himenópteros , Parques Recreativos , Humanos , Animales , Abejas/genética , Pakistán , Código de Barras del ADN Taxonómico/métodos , Insectos/genética , Himenópteros/genética , Plantas/genética
20.
Mol Biol Rep ; 51(1): 528, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637345

RESUMEN

BACKGROUND: Catfishes (order Siluriformes) are among the most diverse and widely distributed fish groups in the world. They are not only used for human consumption but are also a major part of the ornamental fish trade. Being a Biodiversity Hotspot, the North Eastern Region of India is home to a diverse population of ornamental fishes. Catfishes contain a humongous number of species; in this study, the authors have tried to elucidate the phylogenetic relationship of some important ornamental catfishes found in North East India using DNA barcodes. METHODS AND RESULTS: In this study, we have tried to explore the phylogenetic history of 13 species (41 specimens) of ornamental catfishes spanning 12 genera and 9 families of Siluriformes using DNA barcoding. Pairwise genetic distances using Kimura 2-Parameter (K2P) were calculated at intra-specific and inter-specific levels. A Neighbor-Joining tree was constructed to understand the phylogenetic relationship among the nine different catfish families. All the specimens under this study clustered with their respective species under the same family and formed three sub-clades. However, Olyra longicaudata, belonging to the Bagridae family, did not cluster with other species from the same family. In this study, the authors have suggested a revision of the classification of O. longicaudata back to its original family, Olyridae. CONCLUSIONS: In this study, the maximum intraspecific genetic distance of 0.03 and the minimum interspecific genetic distance of 0.14 were observed among the species. Therefore, it is evident that there is a barcoding gap among the species, which helped in the correct identification of the species. Thus, DNA barcoding helped complement the phenetic approach and also revealed a different phylogenetic relationship among the catfishes belonging to the Bagridae family.


Asunto(s)
Bagres , Animales , Humanos , Bagres/genética , Código de Barras del ADN Taxonómico/métodos , Filogenia , ADN , India
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