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1.
Microbiol Spectr ; 12(2): e0340023, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38193680

RESUMO

Fungal secondary metabolites (SMs) contribute to the diversity of fungal ecological communities, niches, and lifestyles. Many fungal SMs have one or more medically and industrially important activities (e.g., antifungal, antibacterial, and antitumor). The genes necessary for fungal SM biosynthesis are typically located right next to each other in the genome and are known as biosynthetic gene clusters (BGCs). However, whether fungal SM bioactivity can be predicted from specific attributes of genes in BGCs remains an open question. We adapted machine learning models that predicted SM bioactivity from bacterial BGC data with accuracies as high as 80% to fungal BGC data. We trained our models to predict the antibacterial, antifungal, and cytotoxic/antitumor bioactivity of fungal SMs on two data sets: (i) fungal BGCs (data set comprised of 314 BGCs) and (ii) fungal (314 BGCs) and bacterial BGCs (1,003 BGCs). We found that models trained on fungal BGCs had balanced accuracies between 51% and 68%, whereas training on bacterial and fungal BGCs had balanced accuracies between 56% and 68%. The low prediction accuracy of fungal SM bioactivities likely stems from the small size of the data set; this lack of data, coupled with our finding that including bacterial BGC data in the training data did not substantially change accuracies currently limits the application of machine learning approaches to fungal SM studies. With >15,000 characterized fungal SMs, millions of putative BGCs in fungal genomes, and increased demand for novel drugs, efforts that systematically link fungal SM bioactivity to BGCs are urgently needed.IMPORTANCEFungi are key sources of natural products and iconic drugs, including penicillin and statins. DNA sequencing has revealed that there are likely millions of biosynthetic pathways in fungal genomes, but the chemical structures and bioactivities of >99% of natural products produced by these pathways remain unknown. We used artificial intelligence to predict the bioactivities of diverse fungal biosynthetic pathways. We found that the accuracies of our predictions were generally low, between 51% and 68%, likely because the natural products and bioactivities of only very few fungal pathways are known. With >15,000 characterized fungal natural products, millions of putative biosynthetic pathways present in fungal genomes, and increased demand for novel drugs, our study suggests that there is an urgent need for efforts that systematically identify fungal biosynthetic pathways, their natural products, and their bioactivities.


Assuntos
Antifúngicos , Produtos Biológicos , Inteligência Artificial , Genoma Fúngico , Vias Biossintéticas/genética , Família Multigênica , Aprendizado de Máquina , Antibacterianos
2.
bioRxiv ; 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37745539

RESUMO

Fungal secondary metabolites (SMs) play a significant role in the diversity of ecological communities, niches, and lifestyles in the fungal kingdom. Many fungal SMs have medically and industrially important properties including antifungal, antibacterial, and antitumor activity, and a single metabolite can display multiple types of bioactivities. The genes necessary for fungal SM biosynthesis are typically found in a single genomic region forming biosynthetic gene clusters (BGCs). However, whether fungal SM bioactivity can be predicted from specific attributes of genes in BGCs remains an open question. We adapted previously used machine learning models for predicting SM bioactivity from bacterial BGC data to fungal BGC data. We trained our models to predict antibacterial, antifungal, and cytotoxic/antitumor bioactivity on two datasets: 1) fungal BGCs (dataset comprised of 314 BGCs), and 2) fungal (314 BGCs) and bacterial BGCs (1,003 BGCs); the second dataset was our control since a previous study using just the bacterial BGC data yielded prediction accuracies as high as 80%. We found that the models trained only on fungal BGCs had balanced accuracies between 51-68%, whereas training on bacterial and fungal BGCs yielded balanced accuracies between 61-74%. The lower accuracy of the predictions from fungal data likely stems from the small number of BGCs and SMs with known bioactivity; this lack of data currently limits the application of machine learning approaches in studying fungal secondary metabolism. However, our data also suggest that machine learning approaches trained on bacterial and fungal data can predict SM bioactivity with good accuracy. With more than 15,000 characterized fungal SMs, millions of putative BGCs present in fungal genomes, and increased demand for novel drugs, efforts that systematically link fungal SM bioactivity to BGCs are urgently needed.

3.
Proc Natl Acad Sci U S A ; 120(10): e2214076120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36848567

RESUMO

Lentinula is a broadly distributed group of fungi that contains the cultivated shiitake mushroom, L. edodes. We sequenced 24 genomes representing eight described species and several unnamed lineages of Lentinula from 15 countries on four continents. Lentinula comprises four major clades that arose in the Oligocene, three in the Americas and one in Asia-Australasia. To expand sampling of shiitake mushrooms, we assembled 60 genomes of L. edodes from China that were previously published as raw Illumina reads and added them to our dataset. Lentinula edodes sensu lato (s. lat.) contains three lineages that may warrant recognition as species, one including a single isolate from Nepal that is the sister group to the rest of L. edodes s. lat., a second with 20 cultivars and 12 wild isolates from China, Japan, Korea, and the Russian Far East, and a third with 28 wild isolates from China, Thailand, and Vietnam. Two additional lineages in China have arisen by hybridization among the second and third groups. Genes encoding cysteine sulfoxide lyase (lecsl) and γ-glutamyl transpeptidase (leggt), which are implicated in biosynthesis of the organosulfur flavor compound lenthionine, have diversified in Lentinula. Paralogs of both genes that are unique to Lentinula (lecsl 3 and leggt 5b) are coordinately up-regulated in fruiting bodies of L. edodes. The pangenome of L. edodes s. lat. contains 20,308 groups of orthologous genes, but only 6,438 orthogroups (32%) are shared among all strains, whereas 3,444 orthogroups (17%) are found only in wild populations, which should be targeted for conservation.


Assuntos
Lentinula , Filogenia , Ásia Oriental , Tailândia
4.
mBio ; 13(2): e0329721, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35311535

RESUMO

Unique DNA repair enzymes that provide self-resistance against therapeutically important, genotoxic natural products have been discovered in bacterial biosynthetic gene clusters (BGCs). Among these, the DNA glycosylase AlkZ is essential for azinomycin B production and belongs to the HTH_42 superfamily of uncharacterized proteins. Despite their widespread existence in antibiotic producers and pathogens, the roles of these proteins in production of other natural products are unknown. Here, we determine the evolutionary relationship and genomic distribution of all HTH_42 proteins from Streptomyces and use a resistance-based genome mining approach to identify homologs associated with known and uncharacterized BGCs. We find that AlkZ-like (AZL) proteins constitute one distinct HTH_42 subfamily and are highly enriched in BGCs and variable in sequence, suggesting each has evolved to protect against a specific secondary metabolite. As a validation of the approach, we show that the AZL protein, HedH4, associated with biosynthesis of the alkylating agent hedamycin, excises hedamycin-DNA adducts with exquisite specificity and provides resistance to the natural product in cells. We also identify a second, phylogenetically and functionally distinct subfamily whose proteins are never associated with BGCs, are highly conserved with respect to sequence and genomic neighborhood, and repair DNA lesions not associated with a particular natural product. This work delineates two related families of DNA repair enzymes-one specific for complex alkyl-DNA lesions and involved in self-resistance to antimicrobials and the other likely involved in protection against an array of genotoxins-and provides a framework for targeted discovery of new genotoxic compounds with therapeutic potential. IMPORTANCE Bacteria are rich sources of secondary metabolites that include DNA-damaging genotoxins with antitumor/antibiotic properties. Although Streptomyces produce a diverse number of therapeutic genotoxins, efforts toward targeted discovery of biosynthetic gene clusters (BGCs) producing DNA-damaging agents is lacking. Moreover, work on toxin-resistance genes has lagged behind our understanding of those involved in natural product synthesis. Here, we identified over 70 uncharacterized BGCs producing potentially novel genotoxins through resistance-based genome mining using the azinomycin B-resistance DNA glycosylase AlkZ. We validate our analysis by characterizing the enzymatic activity and cellular resistance of one AlkZ ortholog in the BGC of hedamycin, a potent DNA alkylating agent. Moreover, we uncover a second, phylogenetically distinct family of proteins related to Escherichia coli YcaQ, a DNA glycosylase capable of unhooking interstrand DNA cross-links, which differs from the AlkZ-like family in sequence, genomic location, proximity to BGCs, and substrate specificity. This work defines two families of DNA glycosylase for specialized repair of complex genotoxic natural products and generalized repair of a broad range of alkyl-DNA adducts and provides a framework for targeted discovery of new compounds with therapeutic potential.


Assuntos
Produtos Biológicos , DNA Glicosilases , Streptomyces , Alquilantes , Antibacterianos/metabolismo , Produtos Biológicos/metabolismo , DNA , Adutos de DNA , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , Mutagênicos , Streptomyces/genética , Streptomyces/metabolismo
5.
Genome Biol Evol ; 13(10)2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34554246

RESUMO

The DNA mismatch repair (MMR) pathway corrects mismatched bases produced during DNA replication and is highly conserved across the tree of life, reflecting its fundamental importance for genome integrity. Loss of function in one or a few MMR genes can lead to increased mutation rates and microsatellite instability, as seen in some human cancers. Although loss of MMR genes has been documented in the context of human disease and in hypermutant strains of pathogens, examples of entire species and species lineages that have experienced substantial MMR gene loss are lacking. We examined the genomes of 1,107 species in the fungal phylum Ascomycota for the presence of 52 genes known to be involved in the MMR pathway of fungi. We found that the median ascomycete genome contained 49/52 MMR genes. In contrast, four closely related species of obligate plant parasites from the powdery mildew genera Erysiphe and Blumeria, have lost between five and 21 MMR genes, including MLH3, EXO1, and DPB11. The lost genes span MMR functions, include genes that are conserved in all other ascomycetes, and loss of function of any of these genes alone has been previously linked to increased mutation rate. Consistent with the hypothesis that loss of these genes impairs MMR pathway function, we found that powdery mildew genomes with higher levels of MMR gene loss exhibit increased numbers of mononucleotide runs, longer microsatellites, accelerated sequence evolution, elevated mutational bias in the A|T direction, and decreased GC content. These results identify a striking example of macroevolutionary loss of multiple MMR pathway genes in a eukaryotic lineage, even though the mutational outcomes of these losses appear to resemble those associated with detrimental MMR dysfunction in other organisms.


Assuntos
Ascomicetos , Reparo de Erro de Pareamento de DNA , Ascomicetos/genética , Reparo de Erro de Pareamento de DNA/genética , Replicação do DNA , Humanos , Mutação , Taxa de Mutação
6.
Microbiol Resour Announc ; 9(49)2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33273000

RESUMO

Aspergillus flavus is an agriculturally and medically important filamentous fungus that produces mycotoxins, including aflatoxins, which are potent carcinogens. Here, we generated short- and long-read transcript sequence data from the growth of A. flavus strain NRRL 3357 under both typical and stress conditions to produce a new annotation of its genome.

7.
mBio ; 11(5)2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051372

RESUMO

G-protein coupled receptors (GPCRs) are extracellular signaling receptors that sense environmental cues. Fungi sense their environment primarily through GPCR-mediated signaling pathways, which, in turn, regulate fungal development, metabolism, virulence, and mycotoxin biosynthesis. Aspergillus fumigatus is an important human pathogen that causes aspergillosis, a heterogeneous group of diseases that present a wide range of clinical manifestations. Here, we investigate in detail the role of the GPCRs GprM and GprJ in growth and gene expression. GprM and GprJ are important for melanin production and the regulation of the cell wall integrity (CWI) pathway. Overexpression of gprM and gprJ causes a 20 and 50% reduction in growth rate compared to the wild-type (WT) strain and increases sensitivity to cell wall-damaging agents. Phosphorylation of the CWI protein kinase MpkA is increased in the ΔgprM and ΔgprJ strains and decreased in the overexpression mutants compared to the WT strain. Furthermore, differences in cell wall polysaccharide concentrations and organization were observed in these strains. Transcriptome sequencing suggests that GprM and GprJ negatively regulate genes encoding secondary metabolites (SMs). Mass spectrometry analysis confirmed that the production of fumagillin, pyripyropene, fumigaclavine C, fumiquinazoline, and fumitremorgin is reduced in the ΔgprM and ΔgprJ strains, at least partially through the activation of MpkA. Overexpression of grpM also resulted in the regulation of many transcription factors, with AsgA predicted to function downstream of GprM and MpkA signaling. Finally, we show that the ΔgprM and ΔgprJ mutants are reduced in virulence in the Galleria mellonella insect model of invasive aspergillosis.IMPORTANCEA. fumigatus is the main etiological agent of invasive pulmonary aspergillosis, a life-threatening fungal disease that occurs in severely immunocompromised humans. Withstanding the host environment is essential for A. fumigatus virulence, and sensing of extracellular cues occurs primarily through G-protein coupled receptors (GPCRs) that activate signal transduction pathways, which, in turn, regulate fungal development, metabolism, virulence, and mycotoxin biosynthesis. The A. fumigatus genome encodes 15 putative classical GPCRs, with only three having been functionally characterized to date. In this work, we show that the two GPCRs GprM and GprJ regulate the phosphorylation of the mitogen-activated protein kinase MpkA and thus control the regulation of the cell wall integrity pathway. GprM and GprJ are also involved in the regulation of the production of the secondary metabolites fumagillin, pyripyropene, fumigaclavine C, fumiquinazoline, melanin, and fumitremorgin, and this regulation partially occurs through the activation of MpkA. Furthermore, GprM and GprJ are important for virulence in the insect model Galleria mellonella This work therefore functionally characterizes two GPCRs and shows how they regulate several intracellular pathways that have been shown to be crucial for A. fumigatus virulence.


Assuntos
Aspergillus fumigatus/genética , Aspergillus fumigatus/patogenicidade , Parede Celular/metabolismo , Proteínas Fúngicas/genética , Receptores Acoplados a Proteínas G/genética , Metabolismo Secundário , Animais , Aspergillus fumigatus/química , Regulação Fúngica da Expressão Gênica , Larva/microbiologia , Macrófagos/microbiologia , Masculino , Melaninas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mariposas/microbiologia , Fagocitose , Fosforilação , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
mSphere ; 5(2)2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32269156

RESUMO

Aspergillus nidulans is an opportunistic fungal pathogen in patients with immunodeficiency, and virulence of A. nidulans isolates has mainly been studied in the context of chronic granulomatous disease (CGD), with characterization of clinical isolates obtained from non-CGD patients remaining elusive. This study therefore carried out a detailed biological characterization of two A. nidulans clinical isolates (CIs), obtained from a patient with breast carcinoma and pneumonia and from a patient with cystic fibrosis that underwent lung transplantation, and compared them to the reference, nonclinical FGSC A4 strain. Both CIs presented increased growth in comparison to that of the reference strain in the presence of physiologically relevant carbon sources. Metabolomic analyses showed that the three strains are metabolically very different from each other in these carbon sources. Furthermore, the CIs were highly susceptible to cell wall-perturbing agents but not to other physiologically relevant stresses. Genome analyses identified several frameshift variants in genes encoding cell wall integrity (CWI) signaling components. Significant differences in CWI signaling were confirmed by Western blotting among the three strains. In vivo virulence studies using several different models revealed that strain MO80069 had significantly higher virulence in hosts with impaired neutrophil function than the other strains. In summary, this study presents detailed biological characterization of two A. nidulanssensu stricto clinical isolates. Just as in Aspergillus fumigatus, strain heterogeneity exists in A. nidulans clinical strains that can define virulence traits. Further studies are required to fully characterize A. nidulans strain-specific virulence traits and pathogenicity.IMPORTANCE Immunocompromised patients are susceptible to infections with opportunistic filamentous fungi from the genus Aspergillus Although A. fumigatus is the main etiological agent of Aspergillus species-related infections, other species, such as A. nidulans, are prevalent in a condition-specific manner. A. nidulans is a predominant infective agent in patients suffering from chronic granulomatous disease (CGD). A. nidulans isolates have mainly been studied in the context of CGD although infection with A. nidulans also occurs in non-CGD patients. This study carried out a detailed biological characterization of two non-CGD A. nidulans clinical isolates and compared the results to those with a reference strain. Phenotypic, metabolomic, and genomic analyses highlight fundamental differences in carbon source utilization, stress responses, and maintenance of cell wall integrity among the strains. One clinical strain had increased virulence in models with impaired neutrophil function. Just as in A. fumigatus, strain heterogeneity exists in A. nidulans clinical strains that can define virulence traits.


Assuntos
Aspergilose/microbiologia , Aspergillus nidulans/genética , Aspergillus nidulans/patogenicidade , Carbono/metabolismo , Metabolômica , Adulto , Animais , Parede Celular/genética , Feminino , Genômica , Doença Granulomatosa Crônica/microbiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neutropenia , Fagocitose , Virulência , Peixe-Zebra/microbiologia
9.
Org Lett ; 22(5): 1878-1882, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32096649

RESUMO

Wheldone (1) was isolated and elucidated from a coculture of Aspergillus fischeri (NRRL 181) and Xylaria flabelliformis (G536), where secondary metabolite biosynthesis was stimulated by antagonism between these fungi. First observed via in situ analysis between these competing fungal cultures, the conditions were scaled to reproducibly generate 1, whose novel structure was elucidated by one- and two-dimensional NMR and mass spectrometry. Compound 1 displayed cytotoxic activity against breast, ovarian, and melanoma cancer cell lines.


Assuntos
Antineoplásicos/química , Ascomicetos/química , Aspergillus/química , Xylariales/química , Antineoplásicos/metabolismo , Técnicas de Cocultura , Espectrometria de Massas , Estrutura Molecular , Metabolismo Secundário , Xylariales/metabolismo
10.
Bioessays ; 41(9): e1900072, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31373044

RESUMO

Novel regulatory elements that enabled expression of pre-existing immune genes in reproductive tissues and novel immune genes with pregnancy-specific roles in eutherians have shaped the evolution of mammalian pregnancy by facilitating the emergence of novel mechanisms for immune regulation over its course. Trade-offs arising from conflicting fitness effects on reproduction and host defenses have further influenced the patterns of genetic variation of these genes. These three mechanisms (novel regulatory elements, novel immune genes, and trade-offs) played a pivotal role in refining the regulation of maternal immune systems during pregnancy in eutherians, likely facilitating the establishment of prolonged direct maternal-fetal contact in eutherians without causing immunological rejection of the genetically distinct fetus.


Assuntos
Eutérios/genética , Eutérios/imunologia , Prenhez/imunologia , Animais , Evolução Biológica , Feminino , Duplicação Gênica , Regulação da Expressão Gênica , Variação Genética , Haplótipos , Humanos , Nascido Vivo , Gravidez , Prenhez/genética , Sequências Reguladoras de Ácido Nucleico , Retroviridae/genética , Seleção Genética
11.
mSphere ; 4(4)2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391280

RESUMO

The genetic stability of every living organism depends on accurate DNA replication and repair systems. Here, we investigated the Aspergillus fumigatusMSH2 mismatch repair (MMR) gene MshA and how it impacts virulence and the evolution of azole resistance. We examined mshA gene variation in 62 environmental and clinical A. fumigatus strains. We have observed 12 strains with variants (18.2%), and 8 strains among them showed missense variants. We demonstrated that A. fumigatusmshA null mutants are haploid and have conserved karyotypes with discrete gross chromosomal rearrangements. The ΔmshA strains are not sensitive to several DNA-damaging agents. The lack of mshA caused a significant reduction of virulence of A. fumigatus in a neutropenic murine model of invasive pulmonary aspergillosis and in the invertebrate alternative model Galleria mellonella Wild-type and ΔmshA populations did not show any significant changes in drug resistance acquisition after they were transferred 10 times in minimal medium in the absence of any stress. However, these populations rapidly acquired virulence in the ΔmshA background and high levels of resistance to posaconazole in the presence of this drug (at least 200-fold-higher levels of resistance than those derived from the wild-type strain). Taken together, these results suggest that genetic instability caused by ΔmshA mutations can confer an adaptive advantage, mainly increasing posaconazole resistance and virulence acquisition.IMPORTANCE Invasive aspergillosis (IA) has emerged as one of the most common life-threatening fungal diseases in immunocompromised patients, with mortality rates as high as 90%. Systemic fungal infections such as IA are usually treated with triazoles; however, epidemiological research has shown that the prevalence of azole-resistant Aspergillus fumigatus isolates has increased significantly over the last decade. There is very little information about the importance of genomic stability for A. fumigatus population structure, azole resistance, and virulence. Here, we decided to investigate whether the mismatch repair system could influence A. fumigatus azole resistance and virulence, focusing on one of the components of this system, MSH2 Although the mutation frequency of mshA (the A. fumigatusMSH2 homologue) is low in environmental and clinical isolates, our results indicate that loss of mshA function can provide increased azole resistance and virulence when selected for. These results demonstrate the importance of genetic instability in A. fumigatus as a possible mechanism of evolving azole resistance and establishing fitness in the host.


Assuntos
Antifúngicos/farmacologia , Aspergillus fumigatus/genética , Aspergillus fumigatus/patogenicidade , Azóis/farmacologia , Farmacorresistência Fúngica , Proteína 2 Homóloga a MutS/genética , Animais , Aspergilose/microbiologia , Aspergillus fumigatus/efeitos dos fármacos , Reparo de Erro de Pareamento de DNA , Feminino , Proteínas Fúngicas/genética , Larva/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Mariposas/microbiologia , Neutropenia , Homologia de Sequência , Virulência
12.
Curr Opin Microbiol ; 51: 22-29, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31071615

RESUMO

Natural products have drastically improved our lives by providing an excellent source of molecules to fight cancer, pathogens, and cardiovascular diseases that have revolutionized medicine. Fungi are prolific producers of diverse natural products and several recent advances in synthetic biology, genetics, bioinformatics, and natural product chemistry have greatly enhanced our ability to efficiently mine their genomes for the discovery of novel drugs. In this article, we provide an overview of improved heterologous expression platforms for targeted production of fungal secondary metabolites, of advances in chemical and bioinformatics dereplication, and of novel bioinformatic platforms to discover biosynthetic genes involved in the production of metabolites with specific bioactivities. These advances, coupled with the presence of vast numbers of biosynthetic gene clusters in fungal genomes whose natural products remain unknown, have revitalized efforts to mine the fungal treasure chest and renewed the promise of discovering new drugs.


Assuntos
Produtos Biológicos/metabolismo , Fungos/metabolismo , Produtos Biológicos/química , Vias Biossintéticas , Descoberta de Drogas , Fungos/química , Fungos/genética , Genoma Fúngico
13.
PLoS Genet ; 14(7): e1007394, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30001343

RESUMO

Preterm birth is a leading cause of morbidity and mortality in infants. Genetic and environmental factors play a role in the susceptibility to preterm birth, but despite many investigations, the genetic basis for preterm birth remain largely unknown. Our objective was to identify rare, possibly damaging, nucleotide variants in mothers from families with recurrent spontaneous preterm births (SPTB). DNA samples from 17 Finnish mothers who delivered at least one infant preterm were subjected to whole exome sequencing. All mothers were of northern Finnish origin and were from seven multiplex families. Additional replication samples of European origin consisted of 93 Danish sister pairs (and two sister triads), all with a history of a preterm delivery. Rare exonic variants (frequency <1%) were analyzed to identify genes and pathways likely to affect SPTB susceptibility. We identified rare, possibly damaging, variants in genes that were common to multiple affected individuals. The glucocorticoid receptor signaling pathway was the most significant (p<1.7e-8) with genes containing these variants in a subgroup of ten Finnish mothers, each having had 2-4 SPTBs. This pathway was replicated among the Danish sister pairs. A gene in this pathway, heat shock protein family A (Hsp70) member 1 like (HSPA1L), contains two likely damaging missense alleles that were found in four different Finnish families. One of the variants (rs34620296) had a higher frequency in cases compared to controls (0.0025 vs. 0.0010, p = 0.002) in a large preterm birth genome-wide association study (GWAS) consisting of mothers of general European ancestry. Sister pairs in replication samples also shared rare, likely damaging HSPA1L variants. Furthermore, in silico analysis predicted an additional phosphorylation site generated by rs34620296 that could potentially affect chaperone activity or HSPA1L protein stability. Finally, in vitro functional experiment showed a link between HSPA1L activity and decidualization. In conclusion, rare, likely damaging, variants in HSPA1L were observed in multiple families with recurrent SPTB.


Assuntos
Predisposição Genética para Doença , Proteínas de Choque Térmico HSP70/genética , Nascimento Prematuro/genética , Difosfato de Adenosina/química , Difosfato de Adenosina/metabolismo , Estudos de Casos e Controles , Linhagem Celular , Exoma/genética , Feminino , Fibroblastos , Finlândia , Estudo de Associação Genômica Ampla , Proteínas de Choque Térmico HSP70/química , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Recém-Nascido , Masculino , Modelos Moleculares , Fosforilação/genética , Polimorfismo de Nucleotídeo Único , Gravidez , Receptores de Glucocorticoides/metabolismo , Recidiva , Fatores de Risco , Transdução de Sinais/genética , Sequenciamento do Exoma
14.
RNA ; 18(5): 915-29, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22408181

RESUMO

During early vertebrate development, a large number of noncoding RNAs are maternally inherited or expressed upon activation of zygotic transcription. The exact identity, expression levels, and function for most of these noncoding RNAs remain largely unknown. miRNAs (microRNAs) and piRNAs (piwi-interacting RNAs) are two classes of small noncoding RNAs that play important roles in gene regulation during early embryonic development. Here, we utilized next-generation sequencing technology to determine temporal expression patterns for both miRNAs and piRNAs during four distinct stages of early vertebrate development using zebrafish as a model system. For miRNAs, the expression patterns for 198 known miRNAs within 122 different miRNA families and eight novel miRNAs were determined. Significant sequence variation was observed at the 5' and 3'ends of miRNAs, with most extra nucleotides added at the 3' end in a nontemplate directed manner. For the miR-430 family, the addition of adenosine and uracil residues is developmentally regulated and may play a role in miRNA stability during the maternal zygotic transition. Similar modification at the 3' ends of a large number of miRNAs suggests widespread regulation of stability during early development. Beside miRNAs, we also identified a large and unexpectedly diverse set of piRNAs expressed during early development.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , MicroRNAs/metabolismo , RNA Interferente Pequeno/metabolismo , Transcriptoma , Peixe-Zebra/genética , Animais , Sequência de Bases , Análise por Conglomerados , Expressão Gênica , Perfilação da Expressão Gênica , MicroRNAs/química , Polimorfismo Genético , RNA Interferente Pequeno/química , RNA de Transferência/química , Análise de Sequência de RNA , Peixe-Zebra/metabolismo
15.
Proc Natl Acad Sci U S A ; 105(8): 3100-5, 2008 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-18287045

RESUMO

One of the hallmarks of the Gram-negative bacterium Pseudomonas aeruginosa is its ability to thrive in diverse environments that includes humans with a variety of debilitating diseases or immune deficiencies. Here we report the complete sequence and comparative analysis of the genomes of two representative P. aeruginosa strains isolated from cystic fibrosis (CF) patients whose genetic disorder predisposes them to infections by this pathogen. The comparison of the genomes of the two CF strains with those of other P. aeruginosa presents a picture of a mosaic genome, consisting of a conserved core component, interrupted in each strain by combinations of specific blocks of genes. These strain-specific segments of the genome are found in limited chromosomal locations, referred to as regions of genomic plasticity. The ability of P. aeruginosa to shape its genomic composition to favor survival in the widest range of environmental reservoirs, with corresponding enhancement of its metabolic capacity is supported by the identification of a genomic island in one of the sequenced CF isolates, encoding enzymes capable of degrading terpenoids produced by trees. This work suggests that niche adaptation is a major evolutionary force influencing the composition of bacterial genomes. Unlike genome reduction seen in host-adapted bacterial pathogens, the genetic capacity of P. aeruginosa is determined by the ability of individual strains to acquire or discard genomic segments, giving rise to strains with customized genomic repertoires. Consequently, this organism can survive in a wide range of environmental reservoirs that can serve as sources of the infecting organisms.


Assuntos
Fibrose Cística/complicações , Meio Ambiente , Evolução Molecular , Genoma Bacteriano , Filogenia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/genética , Sequência de Bases , Genômica , Humanos , Dados de Sequência Molecular , Infecções por Pseudomonas/etiologia , Alinhamento de Sequência , Análise de Sequência de DNA
16.
Mol Ecol ; 16(10): 2103-14, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17498235

RESUMO

The oak gallwasp Andricus coriarius is distributed across the Western Palaearctic from Morocco to Iran. It belongs to a clade of host-alternating Andricus species that requires host oaks in two sections of Quercus subgenus Quercus to complete its lifecycle, a requirement that has restricted the historic distribution and dispersal of members of this clade. Here we present nuclear and mitochondrial sequence evidence from the entire geographic range of A. coriarius to investigate the genetic legacy of longitudinal range expansion. We show A. coriarius as currently understood to be para- or polyphyletic, with three evolutionarily independent (but partially sympatric) lineages that diverged c. 10 million years ago (mya). The similarities in gall structure that have justified recognition of single species to date thus represent either strong conservation of an ancestral state or striking convergence. All three lineages originated in areas to the east of Europe, underlining the significance of Turkey, Iran and the Levant as 'cradles' of gallwasp evolution. One of the three lineages gave rise to all European populations, and range expansion from a putative Eastern origin to the present distribution is predicted to have occurred around 1.6 mya.


Assuntos
Demografia , Filogenia , Quercus/parasitologia , Vespas/genética , Animais , Sequência de Bases , Teorema de Bayes , Primers do DNA , DNA Mitocondrial/genética , Europa (Continente) , Geografia , Haplótipos/genética , Interações Hospedeiro-Parasita , Oriente Médio , Modelos Genéticos , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de DNA , Vespas/classificação
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