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1.
Evol Appl ; 17(6): e13693, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38828055

ABSTRACT

The adaptation of Anopheles malaria vectors to domestic settings is directly linked to their ability to feed on humans. The strength of this species-habitat association is unequal across the species within the genus, with the major vectors being particularly dependent on humans. However, our understanding of how blood-feeding behavior interacts with and adapts to environmental settings, including the presence of humans, remains limited. Using a field-based approach, we first investigated Anopheles community structure and feeding behavior patterns in domestic and sylvatic settings in La Lopé National Park in Gabon, Central Africa. We characterized the preference indices using a dual-host choice sampling approach across mosquito species, habitats, and seasons. We then quantified the plastic biting behavior of mosquito species in each habitat. We collected individuals from 16 Anopheles species that exhibited significant differences in species composition and abundance between sylvatic and domestic settings. The host-seeking behavior also varied among the seven most abundant species. The general attractiveness to each host, human or animal, remained relatively constant for each species, but with significant variations between habitats across species. These variations, to more generalist and to more anthropophilic behavior, were related to seasonal changes and distance from the village, respectively. Finally, we pointed out that the host choice of major malaria vectors changed in the absence of humans, revealing a plastic feeding behavior of these species. This study highlights the effect of humans on Anopheles distribution and feeding evolution. The characterization of feeding behavior in wild and domestic settings provides opportunities to better understand the interplay between genetic determinants of host preference and ecological factors. Our findings suggest that protected areas may offer alternative thriving conditions to major malaria vectors.

2.
bioRxiv ; 2024 May 29.
Article in English | MEDLINE | ID: mdl-38854026

ABSTRACT

A major mechanism of insecticide resistance in insect pests is knock-down resistance (kdr) caused by mutations in the voltage-gated sodium channel (Vgsc) gene. Despite being common in most malaria Anopheles vector species, kdr mutations have never been observed in Anopheles funestus, the principal malaria vector in Eastern and Southern Africa. While monitoring 10 populations of An. funestus in Tanzania, we unexpectedly found resistance to DDT, a banned insecticide, in one location. Through whole-genome sequencing of 333 An. funestus samples from these populations, we found 8 novel amino acid substitutions in the Vgsc gene, including the kdr variant, L976F (L1014F in An. gambiae), in tight linkage disequilibrium with another (P1842S). The mutants were found only at high frequency in one region, with a significant decline between 2017 and 2023. Notably, kdr L976F was strongly associated with survivorship to the exposure to DDT insecticide, while no clear association was noted with a pyrethroid insecticide (deltamethrin). Further study is necessary to identify the origin and spread of kdr in An. funestus, and the potential threat to current insecticide-based vector control in Africa.

3.
Science ; 384(6695): eadj4088, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38696552

ABSTRACT

The developmental decision made by malaria parasites to become sexual underlies all malaria transmission. Here, we describe a rich atlas of short- and long-read single-cell transcriptomes of over 37,000 Plasmodium falciparum cells across intraerythrocytic asexual and sexual development. We used the atlas to explore transcriptional modules and exon usage along sexual development and expanded it to include malaria parasites collected from four Malian individuals naturally infected with multiple P. falciparum strains. We investigated genotypic and transcriptional heterogeneity within and among these wild strains at the single-cell level, finding differential expression between different strains even within the same host. These data are a key addition to the Malaria Cell Atlas interactive data resource, enabling a deeper understanding of the biology and diversity of transmission stages.


Subject(s)
Erythrocytes , Malaria, Falciparum , Plasmodium falciparum , Sexual Development , Humans , Erythrocytes/parasitology , Malaria, Falciparum/parasitology , Malaria, Falciparum/transmission , Plasmodium falciparum/genetics , Plasmodium falciparum/growth & development , Sexual Development/genetics , Single-Cell Analysis , Transcriptome , Atlases as Topic
4.
Microbiol Spectr ; 12(2): e0366923, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38214524

ABSTRACT

Microsporidia are obligate intracellular eukaryotic parasites with an extremely broad host range. They have both economic and public health importance. Ploidy in microsporidia is variable, with a few species formally identified as diploid and one as polyploid. Given the increase in the number of studies sequencing microsporidian genomes, it is now possible to assess ploidy levels across all currently explored microsporidian diversity. We estimate ploidy for all microsporidian data sets available on the Sequence Read Archive using k-mer-based analyses, indicating that polyploidy is widespread in Microsporidia and that ploidy change is dynamic in the group. Using genome-wide heterozygosity estimates, we also show that polyploid microsporidian genomes are relatively homozygous, and we discuss the implications of these findings on the timing of polyploidization events and their origin.IMPORTANCEMicrosporidia are single-celled intracellular parasites, distantly related to fungi, that can infect a broad range of hosts, from humans all the way to protozoans. Exploiting the wealth of microsporidian genomic data available, we use k-mer-based analyses to assess ploidy status across the group. Understanding a genome's ploidy is crucial in order to assemble it effectively and may also be relevant for better understanding a parasite's behavior and life cycle. We show that tetraploidy is present in at least six species in Microsporidia and that these polyploidization events are likely to have occurred independently. We discuss why these findings may be paradoxical, given that Microsporidia, like other intracellular parasites, have extremely small, reduced genomes.


Subject(s)
Microsporidia , Humans , Phylogeny , Evolution, Molecular , Genome, Fungal , Polyploidy
5.
ACS Macro Lett ; 12(10): 1416-1422, 2023 Oct 17.
Article in English | MEDLINE | ID: mdl-37793066

ABSTRACT

With synthetic ease and tunable degradation lifetimes, poly(ß-amino ester)s (PBAEs) have found use in increasingly diverse applications, from gene therapy to thermosets. Protonatable amines in each repeating unit impart pH-dependent solution behavior and lifetimes, with acidic conditions favoring solubility, yet slowing hydrolysis. Due in part to these interconnected phenomena governing pH-dependent PBAE degradation, predictive degradation models, which would enable user-defined lifetimes, remain elusive. To separate the effects of charge state and solution pH on PBAE degradation, we synthesized poly(ß-quaternary ammonium ester)s (PBQAEs), which differ from their parent PBAEs only by an additional methyl group, generating polymers with pH-independent cationic charge. Like PBAEs, PBQAE hydrolysis accelerates with increasing pH, although at a given pH, PBAE degradation outpaces PBQAE degradation. This difference is more pronounced in basic solutions, suggesting that deprotonated PBAE amines accelerate hydrolysis, providing an additional tuning parameter to PBAE lifetime and informing the degradation of PBAEs and other pH-responsive polymers.

6.
Polym Chem ; 14(4): 421-431, 2023 Jan 28.
Article in English | MEDLINE | ID: mdl-37842180

ABSTRACT

As hydrolytically-labile, traditionally-cationic polymers, poly(ß-amino ester)s (PBAEs) adeptly complex anionic compounds such as nucleic acids, and release their cargo as the polymer degrades. To engineer fully-degradable polyelectrolyte complexes and delivery vehicles for cationic therapeutics, we sought to invert PBAE net charge to generate net anionic PBAEs. Since PBAEs can carry up to a net charge of +1 per tertiary amine, we synthesized a series of alkyne-functionalized PBAEs that allowed installation of 2 anionic thiol-containing molecules per tertiary amine via a radical thiol-yne reaction. Finding dialysis in aqueous solution to lead to PBAE degradation, we developed a preparative size exclusion chromatography method to remove unreacted thiol from the net anionic PBAEs without triggering hydrolysis. The net anionic PBAEs display non-monotonic solution behavior as a function of pH, being more soluble at pH 4 and 10 than in intermediate pH ranges. Like cationic PBAEs, these net anionic PBAEs degrade in aqueous environments with hydrophobic content-dependent hydrolysis, as determined by 1H NMR spectroscopy. Further, these net anionic PBAEs form complexes with the cationic peptide (GR)10, which disintegrate over time as the polymer hydrolyzes. Together, these studies outline a synthesis and purification route to make previously inaccessible net anionic PBAEs with tunable solution and degradation behavior, allowing for user-determined complexation and release rates and providing opportunities for degradable polyelectrolyte complexes and cationic therapeutic delivery.

7.
J Voice ; 2023 Oct 12.
Article in English | MEDLINE | ID: mdl-37838586

ABSTRACT

OBJECTIVE: Verify the results from intensive short-term vocal therapy using the Finger Kazoo technique about the spectrographic vocal measurements of teachers. METHODS: Controlled and randomized trial. Spectrographic vocal assessment was performed by judges before and after intensive short-term vocal therapy with Finger Kazoo. Sample was composed of 41 female teachers. There were two study groups (with vocal nodules and without structural affection of the vocal folds) and the respective control groups. For the statistical analysis of the data, nonparametric tests were used (Mann-Whitney test and Wilcoxon test). RESULTS: After intensive short-term vocal therapy with Finger Kazoo, improvement in voice spectral parameters, such as improvement in tracing (color intensity and regularity), greater definition of formants and harmonics, increased replacement of harmonics by noise, and a greater number of harmonics, mainly in the group without structural affection of the vocal folds. CONCLUSION: There was an improvement in the spectrographic vocal parameters, showing greater stability, quality, and projection of the emission, especially in female teachers without structural affection of the vocal folds.

8.
Wellcome Open Res ; 8: 74, 2023.
Article in English | MEDLINE | ID: mdl-37424773

ABSTRACT

We present a genome assembly from an individual female Anopheles gambiae (the malaria mosquito; Arthropoda; Insecta; Diptera; Culicidae), Ifakara strain. The genome sequence is 264 megabases in span. Most of the assembly is scaffolded into three chromosomal pseudomolecules with the X sex chromosome assembled. The complete mitochondrial genome was also assembled and is 15.4 kilobases in length.

9.
Curr Top Dev Biol ; 154: 245-283, 2023.
Article in English | MEDLINE | ID: mdl-37100520

ABSTRACT

Mammary gland development and breast cancer progression are associated with extensive remodeling of epithelial tissue architecture. Apical-basal polarity is a key feature of epithelial cells that coordinates key elements of epithelial morphogenesis including cell organization, proliferation, survival, and migration. In this review we discuss advances in our understanding of how apical-basal polarity programs are used in breast development and cancer. We describe cell lines, organoids, and in vivo models commonly used for studying apical-basal polarity in breast development and disease and discuss advantages and limitations of each. We also provide examples of how core polarity proteins regulate branching morphogenesis and lactation during development. We describe alterations to core polarity genes in breast cancer and their associations with patient outcomes. The impact of up- or down-regulation of key polarity proteins in breast cancer initiation, growth, invasion, metastasis, and therapeutic resistance are discussed. We also introduce studies demonstrating that polarity programs are involved in regulating the stroma, either through epithelial-stroma crosstalk, or through signaling of polarity proteins in non-epithelial cell types. Overall, a key concept is that the function of individual polarity proteins is highly contextual, depending on developmental or cancer stage and cancer subtype.


Subject(s)
Breast Neoplasms , Epithelial Cells , Female , Humans , Epithelium/metabolism , Epithelial Cells/metabolism , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Signal Transduction/genetics , Morphogenesis/genetics , Cell Polarity/genetics
10.
Trends Genet ; 39(7): 531-544, 2023 07.
Article in English | MEDLINE | ID: mdl-36907721

ABSTRACT

Insects are crucial for ecosystem health but climate change and pesticide use are driving massive insect decline. To mitigate this loss, we need new and effective monitoring techniques. Over the past decade there has been a shift to DNA-based techniques. We describe key emerging techniques for sample collection. We suggest that the selection of tools should be broadened, and that DNA-based insect monitoring data need to be integrated more rapidly into policymaking. We argue that there are four key areas for advancement, including the generation of more complete DNA barcode databases to interpret molecular data, standardisation of molecular methods, scaling up of monitoring efforts, and integrating molecular tools with other technologies that allow continuous, passive monitoring based on images and/or laser imaging, detection, and ranging (LIDAR).


Subject(s)
Biodiversity , Ecosystem , Animals , DNA Barcoding, Taxonomic/methods , DNA/genetics , Insecta/genetics
11.
Cell Host Microbe ; 31(2): 305-319.e10, 2023 02 08.
Article in English | MEDLINE | ID: mdl-36634679

ABSTRACT

Malaria transmission to mosquitoes requires a developmental switch in asexually dividing blood-stage parasites to sexual reproduction. In Plasmodium berghei, the transcription factor AP2-G is required and sufficient for this switch, but how a particular sex is determined in a haploid parasite remains unknown. Using a global screen of barcoded mutants, we here identify genes essential for the formation of either male or female sexual forms and validate their importance for transmission. High-resolution single-cell transcriptomics of ten mutant parasites portrays the developmental bifurcation and reveals a regulatory cascade of putative gene functions in the determination and subsequent differentiation of each sex. A male-determining gene with a LOTUS/OST-HTH domain as well as the protein interactors of a female-determining zinc-finger protein indicate that germ-granule-like ribonucleoprotein complexes complement transcriptional processes in the regulation of both male and female development of a malaria parasite.


Subject(s)
Culicidae , Malaria , Parasites , Animals , Female , Male , Parasites/metabolism , Malaria/parasitology , Plasmodium berghei/genetics , Sexual Development/genetics , Culicidae/parasitology , Protozoan Proteins/genetics , Protozoan Proteins/metabolism
12.
Wellcome Open Res ; 8: 379, 2023.
Article in English | MEDLINE | ID: mdl-38533437

ABSTRACT

We present a genome assembly from an individual male Bombylius major (the dark-edged bee fly; Arthropoda; Insecta; Diptera; Bombyliidae). The genome sequence is 304.3 megabases in span. The whole assembly is scaffolded into 7 chromosomal pseudomolecules, including the X and Y sex chromosomes. The mitochondrial genome has also been assembled and is 17.8 kilobases in length. Gene annotation of this assembly on Ensembl identified 10,852 protein coding genes.

13.
Elife ; 112022 Oct 12.
Article in English | MEDLINE | ID: mdl-36222650

ABSTRACT

The ANOSPP amplicon panel is a genus-wide targeted sequencing panel to facilitate large-scale monitoring of Anopheles species diversity. Combining information from the 62 nuclear amplicons present in the ANOSPP panel allows for a more senstive and specific species assignment than single gene (e.g. COI) barcoding, which is desirable in the light of permeable species boundaries. Here, we present NNoVAE, a method using Nearest Neighbours (NN) and Variational Autoencoders (VAE), which we apply to k-mers resulting from the ANOSPP amplicon sequences in order to hierarchically assign species identity. The NN step assigns a sample to a species-group by comparing the k-mers arising from each haplotype's amplicon sequence to a reference database. The VAE step is required to distinguish between closely related species, and also has sufficient resolution to reveal population structure within species. In tests on independent samples with over 80% amplicon coverage, NNoVAE correctly classifies to species level 98% of samples within the An. gambiae complex and 89% of samples outside the complex. We apply NNoVAE to over two thousand new samples from Burkina Faso and Gabon, identifying unexpected species in Gabon. NNoVAE presents an approach that may be of value to other targeted sequencing panels, and is a method that will be used to survey Anopheles species diversity and Plasmodium transmission patterns through space and time on a large scale, with plans to analyse half a million mosquitoes in the next five years.


Subject(s)
Anopheles , Animals , Anopheles/genetics , Burkina Faso , Gabon
14.
Contraception ; 114: 6-9, 2022 10.
Article in English | MEDLINE | ID: mdl-35753404

ABSTRACT

Abortion and contraception are essential components of reproductive healthcare. As 26 states are likely to severely restrict access to abortion following the Supreme Court decision in Dobbs v. Jackson Women's Health Organization, access to emergency contraception will be more important than ever. Existing barriers to emergency contraception - including cost, obstacles to over-the-counter purchase, low awareness and availability of the most effective options, myths about safety and mechanism of action - already substantially limit access. Proactive solutions include public information campaigns; healthcare provider education about all emergency contraceptive options, including IUDs and advance provision of emergency contraceptive pills; innovative service delivery options such as vending machines and community distribution programs; and policy initiatives to ensure insurance coverage, eliminate pharmacy refusals, and support all service delivery options. In addition, we urge the U.S. Food and Drug Administration to approve updated labeling to align with the best available evidence that oral contraceptive pills work before ovulation and do not prevent implantation of a fertilized egg, as this language contributes to public confusion and access barriers. In the face of extreme limits on reproductive healthcare, now is the time to expand and protect access to emergency contraception so that everyone has the possibility of preventing pregnancy after unprotected sex or sexual assault.


Subject(s)
Abortion, Induced , Contraception, Postcoital , Contraceptives, Postcoital , Intrauterine Devices , Contraception , Contraceptives, Oral , Female , Humans , Pregnancy , United States
16.
PLoS Pathog ; 18(3): e1010346, 2022 03.
Article in English | MEDLINE | ID: mdl-35255094

ABSTRACT

Early diverging lineages such as trypanosomes can provide clues to the evolution of sexual reproduction in eukaryotes. In Trypanosoma brucei, the pathogen that causes Human African Trypanosomiasis, sexual reproduction occurs in the salivary glands of the insect host, but analysis of the molecular signatures that define these sexual forms is complicated because they mingle with more numerous, mitotically-dividing developmental stages. We used single-cell RNA-sequencing (scRNAseq) to profile 388 individual trypanosomes from midgut, proventriculus, and salivary glands of infected tsetse flies allowing us to identify tissue-specific cell types. Further investigation of salivary gland parasite transcriptomes revealed fine-scale changes in gene expression over a developmental progression from putative sexual forms through metacyclics expressing variant surface glycoprotein genes. The cluster of cells potentially containing sexual forms was characterized by high level transcription of the gamete fusion protein HAP2, together with an array of surface proteins and several genes of unknown function. We linked these expression patterns to distinct morphological forms using immunofluorescence assays and reporter gene expression to demonstrate that the kinetoplastid-conserved gene Tb927.10.12080 is exclusively expressed at high levels by meiotic intermediates and gametes. Further experiments are required to establish whether this protein, currently of unknown function, plays a role in gamete formation and/or fusion.


Subject(s)
Trypanosoma brucei brucei , Trypanosoma , Trypanosomiasis, African , Tsetse Flies , Animals , Transcriptome , Trypanosoma/genetics , Trypanosoma brucei brucei/genetics , Trypanosomiasis, African/parasitology , Tsetse Flies/genetics , Tsetse Flies/parasitology
17.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Article in English | MEDLINE | ID: mdl-35042801

ABSTRACT

Life on Earth has evolved from initial simplicity to the astounding complexity we experience today. Bacteria and archaea have largely excelled in metabolic diversification, but eukaryotes additionally display abundant morphological innovation. How have these innovations come about and what constraints are there on the origins of novelty and the continuing maintenance of biodiversity on Earth? The history of life and the code for the working parts of cells and systems are written in the genome. The Earth BioGenome Project has proposed that the genomes of all extant, named eukaryotes-about 2 million species-should be sequenced to high quality to produce a digital library of life on Earth, beginning with strategic phylogenetic, ecological, and high-impact priorities. Here we discuss why we should sequence all eukaryotic species, not just a representative few scattered across the many branches of the tree of life. We suggest that many questions of evolutionary and ecological significance will only be addressable when whole-genome data representing divergences at all of the branchings in the tree of life or all species in natural ecosystems are available. We envisage that a genomic tree of life will foster understanding of the ongoing processes of speciation, adaptation, and organismal dependencies within entire ecosystems. These explorations will resolve long-standing problems in phylogenetics, evolution, ecology, conservation, agriculture, bioindustry, and medicine.


Subject(s)
Base Sequence/genetics , Eukaryota/genetics , Genomics/ethics , Animals , Biodiversity , Biological Evolution , Ecology , Ecosystem , Genome , Genomics/methods , Humans , Phylogeny
18.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Article in English | MEDLINE | ID: mdl-35042802

ABSTRACT

A global international initiative, such as the Earth BioGenome Project (EBP), requires both agreement and coordination on standards to ensure that the collective effort generates rapid progress toward its goals. To this end, the EBP initiated five technical standards committees comprising volunteer members from the global genomics scientific community: Sample Collection and Processing, Sequencing and Assembly, Annotation, Analysis, and IT and Informatics. The current versions of the resulting standards documents are available on the EBP website, with the recognition that opportunities, technologies, and challenges may improve or change in the future, requiring flexibility for the EBP to meet its goals. Here, we describe some highlights from the proposed standards, and areas where additional challenges will need to be met.


Subject(s)
Base Sequence/genetics , Eukaryota/genetics , Genomics/standards , Animals , Biodiversity , Genomics/methods , Humans , Reference Standards , Reference Values , Sequence Analysis, DNA/methods , Sequence Analysis, DNA/standards
19.
Wellcome Open Res ; 7: 126, 2022.
Article in English | MEDLINE | ID: mdl-36874573

ABSTRACT

We present a genome assembly from an individual Patella pellucida (the blue-rayed limpet; Mollusca; Gastropoda; Patellidae). The genome sequence is 712 megabases in span. The majority of the assembly (99.85%) is scaffolded into 9 chromosomal pseudomolecules. The mitochondrial genome was assembled and is 14.9 kilobases in length.

20.
Mol Ecol Resour ; 22(1): 28-44, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34053186

ABSTRACT

Anopheles is a diverse genus of mosquitoes comprising over 500 described species, including all known human malaria vectors. While a limited number of key vector species have been studied in detail, the goal of malaria elimination calls for surveillance of all potential vector species. Here, we develop a multilocus amplicon sequencing approach that targets 62 highly variable loci in the Anopheles genome and two conserved loci in the Plasmodium mitochondrion, simultaneously revealing both the mosquito species and whether that mosquito carries malaria parasites. We also develop a cheap, nondestructive, and high-throughput DNA extraction workflow that provides template DNA from single mosquitoes for the multiplex PCR, which means specimens producing unexpected results can be returned to for morphological examination. Over 1000 individual mosquitoes can be sequenced in a single MiSeq run, and we demonstrate the panel's power to assign species identity using sequencing data for 40 species from Africa, Southeast Asia, and South America. We also show that the approach can be used to resolve geographic population structure within An. gambiae and An. coluzzii populations, as the population structure determined based on these 62 loci from over 1000 mosquitoes closely mirrors that revealed through whole genome sequencing. The end-to-end approach is quick, inexpensive, robust, and accurate, which makes it a promising technique for very large-scale mosquito genetic surveillance and vector control.


Subject(s)
Anopheles , Plasmodium , Africa , Animals , Anopheles/genetics , Humans , Mosquito Vectors/genetics , Plasmodium/genetics
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