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1.
Nature ; 584(7821): 403-409, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32760000

RESUMEN

The tuatara (Sphenodon punctatus)-the only living member of the reptilian order Rhynchocephalia (Sphenodontia), once widespread across Gondwana1,2-is an iconic species that is endemic to New Zealand2,3. A key link to the now-extinct stem reptiles (from which dinosaurs, modern reptiles, birds and mammals evolved), the tuatara provides key insights into the ancestral amniotes2,4. Here we analyse the genome of the tuatara, which-at approximately 5 Gb-is among the largest of the vertebrate genomes yet assembled. Our analyses of this genome, along with comparisons with other vertebrate genomes, reinforce the uniqueness of the tuatara. Phylogenetic analyses indicate that the tuatara lineage diverged from that of snakes and lizards around 250 million years ago. This lineage also shows moderate rates of molecular evolution, with instances of punctuated evolution. Our genome sequence analysis identifies expansions of proteins, non-protein-coding RNA families and repeat elements, the latter of which show an amalgam of reptilian and mammalian features. The sequencing of the tuatara genome provides a valuable resource for deep comparative analyses of tetrapods, as well as for tuatara biology and conservation. Our study also provides important insights into both the technical challenges and the cultural obligations that are associated with genome sequencing.


Asunto(s)
Evolución Molecular , Genoma/genética , Filogenia , Reptiles/genética , Animales , Conservación de los Recursos Naturales/tendencias , Femenino , Genética de Población , Lagartos/genética , Masculino , Anotación de Secuencia Molecular , Nueva Zelanda , Caracteres Sexuales , Serpientes/genética , Sintenía
3.
Lancet Oncol ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38944050

RESUMEN

BACKGROUND: There are limited data on the risks of obstetric complications among survivors of adolescent and young adult cancer with most previous studies only reporting risks for all types of cancers combined. The aim of this study was to quantify deficits in birth rates and risks of obstetric complications for female survivors of 17 specific types of adolescent and young adult cancer. METHODS: The Teenage and Young Adult Cancer Survivor Study (TYACSS)-a retrospective, population-based cohort of 200 945 5-year survivors of cancer diagnosed at age 15-39 years from England and Wales-was linked to the English Hospital Episode Statistics (HES) database from April 1, 1997, to March 31, 2022. The cohort included 17 different types of adolescent and young adult cancers. We ascertained 27 specific obstetric complications through HES among 96 947 women in the TYACSS cohort. Observed and expected numbers for births and obstetric complications were compared between the study cohort and the general population of England to identify survivors of adolescent and young adult cancer at a heighted risk of birth deficits and obstetric complications relative to the general population. FINDINGS: Between April 1, 1997, and March 31, 2022, 21 437 births were observed among 13 886 female survivors of adolescent and young adult cancer from England, which was lower than expected (observed-to-expected ratio: 0·68, 95% CI 0·67-0·69). Other survivors of genitourinary, cervical, and breast cancer had under 50% of expected births. Focusing on more common (observed ≥100) obstetric complications that were at least moderately in excess (observed-to-expected ratio ≥1·25), survivors of cervical cancer were at risk of malpresentation of fetus, obstructed labour, amniotic fluid and membranes disorders, premature rupture of membranes, preterm birth, placental disorders including placenta praevia, and antepartum haemorrhage. Survivors of leukaemia were at risk of preterm delivery, obstructed labour, postpartum haemorrhage, and retained placenta. Survivors of all other specific cancers had no more than two obstetric complications that exceeded an observed-to-expected ratio of 1·25 or greater. INTERPRETATION: Survivors of cervical cancer and leukaemia are at risk of several serious obstetric complications; therefore, any pregnancy should be considered high-risk and would benefit from obstetrician-led antenatal care. Despite observing deficits in birth rates across all 17 different types of adolescent and young adult cancer, we provide reassurance for almost all survivors of adolescent and young adult cancer concerning their risk of almost all obstetric complications. Our results provide evidence for the development of clinical guidelines relating to counselling and surveillance of obstetrical risk for female survivors of adolescent and young adult cancer. FUNDING: Children with Cancer UK, The Brain Tumour Charity, and Academy of Medical Sciences.

4.
Br J Cancer ; 130(6): 976-986, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38243010

RESUMEN

BACKGROUND: Childhood cancer survivors are at risk of subsequent gliomas and meningiomas, but the risks beyond age 40 years are uncertain. We quantified these risks in the largest ever cohort. METHODS: Using data from 69,460 5-year childhood cancer survivors (diagnosed 1940-2008), across Europe, standardized incidence ratios (SIRs) and cumulative incidence were calculated. RESULTS: In total, 279 glioma and 761 meningioma were identified. CNS tumour (SIR: 16.2, 95% CI: 13.7, 19.2) and leukaemia (SIR: 11.2, 95% CI: 8.8, 14.2) survivors were at greatest risk of glioma. The SIR for CNS tumour survivors was still 4.3-fold after age 50 (95% CI: 1.9, 9.6), and for leukaemia survivors still 10.2-fold after age 40 (95% CI: 4.9, 21.4). Following cranial radiotherapy (CRT), the cumulative incidence of a glioma in CNS tumour survivors was 2.7%, 3.7% and 5.0% by ages 40, 50 and 60, respectively, whilst for leukaemia this was 1.2% and 1.7% by ages 40 and 50. The cumulative incidence of a meningioma after CRT in CNS tumour survivors doubled from 5.9% to 12.5% between ages 40 and 60, and in leukaemia survivors increased from 5.8% to 10.2% between ages 40 and 50. DISCUSSION: Clinicians following up survivors should be aware that the substantial risks of meningioma and glioma following CRT are sustained beyond age 40 and be vigilant for symptoms.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Glioma , Leucemia , Neoplasias Meníngeas , Meningioma , Neoplasias Primarias Secundarias , Humanos , Adolescente , Adulto , Persona de Mediana Edad , Meningioma/etiología , Meningioma/complicaciones , Factores de Riesgo , Neoplasias Primarias Secundarias/epidemiología , Neoplasias Primarias Secundarias/etiología , Neoplasias del Sistema Nervioso Central/epidemiología , Glioma/epidemiología , Sobrevivientes , Leucemia/epidemiología , Europa (Continente)/epidemiología , Neoplasias Meníngeas/epidemiología , Incidencia
5.
New Phytol ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38922927

RESUMEN

Leaf mould, caused by Fulvia fulva, is a devastating disease of tomato plants. In many commercial tomato cultivars, resistance to this disease is governed by the Cf-9 locus, which encodes five paralogous receptor-like proteins. Two of these proteins confer resistance: Cf-9C recognises the previously identified F. fulva effector Avr9 and provides resistance during all plant growth stages, while Cf-9B recognises the yet-unidentified F. fulva effector Avr9B and provides mature plant resistance only. In recent years, F. fulva strains have emerged that can overcome the Cf-9 locus, with Cf-9C circumvented through Avr9 deletion. To understand how Cf-9B is circumvented, we set out to identify Avr9B. Comparative genomics, transient expression assays and gene complementation experiments were used to identify Avr9B, while gene sequencing was used to assess Avr9B allelic variation across a world-wide strain collection. A strict correlation between Avr9 deletion and resistance-breaking mutations in Avr9B was observed in strains recently collected from Cf-9 cultivars, whereas Avr9 deletion but no mutations in Avr9B were observed in older strains. This research showcases how F. fulva has evolved to sequentially break down the Cf-9 locus and stresses the urgent need for commercial tomato cultivars that carry novel, stacked resistance genes active against this pathogen.

6.
Cancer ; 129(3): 426-440, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36444554

RESUMEN

BACKGROUND: Survivors of Hodgkin lymphoma (HL) are at risk of developing non-Hodgkin lymphoma (NHL) after treatment; however, the risks of developing subsequent primary lymphomas (SPLs), including HL and NHL, after different types of childhood cancer are unknown. The authors quantified the risk of SPLs using the largest cohort of childhood cancer survivors worldwide. METHODS: The Pan-European Network for Care of Survivors After Childhood and Adolescent Cancer (PanCare) Survivor Care and Follow-Up Studies (PanCareSurFup) cohort includes 69,460 five-year survivors of childhood cancer, diagnosed during 1940 through 2008, from 12 European countries. Risks of SPLs were quantified by standardized incidence ratios (SIRs) and relative risks (RRs) using multivariable Poisson regression. RESULTS: Overall, 140 SPLs, including 104 NHLs and 36 HLs, were identified. Survivors were at 60% increased risk of an SPL compared with the general population (SIR, 1.6; 95% confidence interval [CI], 1.4-1.9). Survivors were twice as likely to develop NHL (SIR, 2.3; 95% CI, 1.9-2.8), with the greatest risks among survivors of HL (SIR, 7.1; 95% CI, 5.1-10.0), Wilms tumor (SIR, 3.1; 95% CI, 1.7-5.7), leukemia (SIR, 2.8; 95% CI, 1.8-4.4), and bone sarcoma (SIR, 2.7; 95% CI, 1.4-5.4). Treatment with chemotherapy for any cancer doubled the RR of NHL (RR, 2.1; 95% CI, 1.2-3.9), but treatment with radiotherapy did not (RR, 1.2; 95% CI, 0.7-2.0). Survivors were at similar risk of developing a subsequent HL as the general population (SIR, 1.1; 95% CI, 0.8-1.5). CONCLUSIONS: In addition to HL, the authors show here for the first time that survivors of Wilms tumor, leukemia, and bone sarcoma are at risk of NHL. Survivors and health care professionals should be aware of the risk of NHL in these survivors and in any survivors treated with chemotherapy.


Asunto(s)
Neoplasias Óseas , Enfermedad de Hodgkin , Neoplasias Renales , Leucemia , Linfoma no Hodgkin , Linfoma , Neoplasias Primarias Secundarias , Osteosarcoma , Sarcoma , Tumor de Wilms , Humanos , Adolescente , Factores de Riesgo , Neoplasias Primarias Secundarias/epidemiología , Neoplasias Primarias Secundarias/etiología , Linfoma/epidemiología , Linfoma/complicaciones , Sobrevivientes , Linfoma no Hodgkin/terapia , Enfermedad de Hodgkin/epidemiología , Enfermedad de Hodgkin/complicaciones , Leucemia/epidemiología , Sarcoma/epidemiología , Europa (Continente)/epidemiología , Neoplasias Óseas/complicaciones , Tumor de Wilms/complicaciones , Incidencia , Neoplasias Renales/complicaciones
7.
Br J Cancer ; 128(1): 80-90, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36319851

RESUMEN

BACKGROUND: Survivors of childhood cancer are at risk of subsequent primary malignant neoplasms (SPNs), but the risk for rarer types of SPNs, such as oral cancer, is uncertain. Previous studies included few oral SPNs, hence large-scale cohorts are required to identify groups at risks. METHODS: The PanCareSurFup cohort includes 69,460 5-year survivors of childhood cancer across Europe. Risks of oral SPNs were defined by standardised incidence ratios (SIRs), absolute excess risks and cumulative incidence. RESULTS: One hundred and forty-five oral SPNs (64 salivary gland, 38 tongue, 20 pharynx, 2 lip, and 21 other) were ascertained among 143 survivors. Survivors were at 5-fold risk of an oral SPN (95% CI: 4.4-5.6). Survivors of leukaemia were at greatest risk (SIR = 19.2; 95% CI: 14.6-25.2) followed by bone sarcoma (SIR = 6.4, 95% CI: 3.7-11.0), Hodgkin lymphoma (SIR = 6.2, 95% CI: 3.9-9.9) and soft-tissue sarcoma (SIR = 5.0, 95% CI: 3.0-8.5). Survivors treated with radiotherapy were at 33-fold risk of salivary gland SPNs (95% CI: 25.3-44.5), particularly Hodgkin lymphoma (SIR = 66.2, 95% CI: 43.6-100.5) and leukaemia (SIR = 50.5, 95% CI: 36.1-70.7) survivors. Survivors treated with chemotherapy had a substantially increased risk of a tongue SPN (SIR = 15.9, 95% CI: 10.6-23.7). CONCLUSIONS: Previous radiotherapy increases the risk of salivary gland SPNs considerably, while chemotherapy increases the risk of tongue SPNs substantially. Awareness of these risks among both health-care professionals and survivors could play a crucial role in detecting oral SPNs early.


Asunto(s)
Neoplasias Óseas , Enfermedad de Hodgkin , Leucemia , Neoplasias de la Boca , Neoplasias Primarias Secundarias , Sarcoma , Humanos , Adolescente , Factores de Riesgo , Neoplasias Primarias Secundarias/epidemiología , Neoplasias Primarias Secundarias/etiología , Sobrevivientes , Europa (Continente)/epidemiología , Neoplasias Óseas/complicaciones , Leucemia/epidemiología , Incidencia , Neoplasias de la Boca/epidemiología , Neoplasias de la Boca/etiología
8.
BMC Med ; 21(1): 213, 2023 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-37316857

RESUMEN

BACKGROUND: Genomic technologies have become routine in the surveillance and monitoring of the coronavirus disease 2019 (COVID-19) pandemic, as evidenced by the millions of SARS-CoV-2 sequences uploaded to international databases. Yet the ways in which these technologies have been applied to manage the pandemic are varied. MAIN TEXT: Aotearoa New Zealand was one of a small number of countries to adopt an elimination strategy for COVID-19, establishing a managed isolation and quarantine system for all international arrivals. To aid our response, we rapidly set up and scaled our use of genomic technologies to help identify community cases of COVID-19, to understand how they had arisen, and to determine the appropriate action to maintain elimination. Once New Zealand pivoted from elimination to suppression in late 2021, our genomic response changed to focusing on identifying new variants arriving at the border, tracking their incidence around the country, and examining any links between specific variants and increased disease severity. Wastewater detection, quantitation and variant detection were also phased into the response. Here, we explore New Zealand's genomic journey through the pandemic and provide a high-level overview of the lessons learned and potential future capabilities to better prepare for future pandemics. CONCLUSIONS: Our commentary is aimed at health professionals and decision-makers who might not be familiar with genetic technologies, how they can be used, and why this is an area with great potential to assist in disease detection and tracking now and in the future.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Genómica , Nueva Zelanda/epidemiología , Pandemias , SARS-CoV-2/genética
9.
J Evol Biol ; 35(8): 1126-1137, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35830478

RESUMEN

Hybridization is a route to speciation that occurs widely across the eukaryote tree of life. The success of allopolyploids (hybrid species with increased ploidy) and homoploid hybrids (with unchanged ploidy) is well documented. However, their formation and establishment is not straightforward, with a suite of near-instantaneous and longer term biological repercussions faced by the new species. Central to these challenges is the rewiring of gene regulatory networks following the merger of distinct genomes inherited from both parental species. Research on the evolution of hybrid gene expression has largely involved studies on a single hybrid species or a few gene families. Here, we present the first standardized transcriptome-wide study exploring the fates of genes following hybridization across three kingdoms: animals, plants and fungi. Within each kingdom, we pair an allopolyploid system with a closely related homoploid hybrid to decouple the influence of increased ploidy from genome merger. Genome merger, not changes in ploidy, has the greatest effect on posthybridization expression patterns across all study systems. Strikingly, we find that differentially expressed genes in parent species preferentially switch to more similar expression in hybrids across all kingdoms, likely as a consequence of regulatory trans-acting cross-talk within the hybrid nucleus. We also highlight the prevalence of gene loss or silencing among extremely differentially expressed genes in hybrid species across all kingdoms. These shared patterns suggest that the evolutionary process of hybridization leads to common high-level expression outcomes, regardless of the particular species or kingdom.


Asunto(s)
Hibridación Genética , Transcriptoma , Animales , Eucariontes/genética , Genoma , Ploidias
10.
Genomics ; 113(6): 4267-4275, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34774981

RESUMEN

Epichloe fungi are endophytes of cool season grasses, both wild species and commercial cultivars, where they may exhibit mutualistic or pathogenic lifestyles. The Epichloe-grass symbiosis is of great interest to agricultural research for the fungal bioprotective properties conferred to host grasses but also serves as an ideal system to study the evolution of fungal plant-pathogens in natural environments. Here, we assembled and annotated gapless chromosome-level genomes of two pathogenic Epichloe sibling species. Both genomes have a bipartite genome organization, with blocks of highly syntenic gene-rich regions separated by blocks of AT-rich DNA. The AT-rich regions show an extensive signature of RIP (repeat-induced point mutation) and the expansion of this compartment accounts for the large difference in genome size between the two species. This study reveals how the rapid evolution of repeat structure can drive divergence between closely related taxa and highlights the evolutionary role of dynamic compartments in fungal genomes.


Asunto(s)
Epichloe , Cromosomas , Endófitos/genética , Epichloe/genética , Evolución Molecular , Genoma Fúngico , Poaceae/genética , Simbiosis/genética
11.
J Struct Biol ; 213(4): 107793, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34481988

RESUMEN

On the basis of sequence homology with mammalian α-keratins, and on the criteria that the coiled-coil segments and central linker in the rod domain of these molecules must have conserved lengths if they are to assemble into viable intermediate filaments, a total of 28 Type I and Type II keratin intermediate filament chains (KIF) have been identified from the genome of the European common wall lizard (Podarcis muralis). Using the same criteria this number may be compared to 33 found here in the green anole lizard (Anole carolinensis) and 25 in the tuatara (Sphenodon punctatus). The Type I and Type II KIF genes in the wall lizard fall in clusters on chromosomes 13 and 2 respectively. Although some differences occur in the terminal domains in the KIF chains of the two lizards and tuatara, the similarities between key indicator residues - cysteine, glycine and proline - are significant. The terminal domains of the KIF chains in the wall lizard also contain sequence repeats commonly based on glycine and large apolar residues and would permit the fine tuning of physical properties when incorporated within the intermediate filaments. The H1 domain in the Type II chain is conserved across the lizards, tuatara and mammals, and has been related to its role in assembly at the 2-4 molecule level. A KIF-like chain (K80) with an extensive tail domain comprised of multiple tandem repeats has been identified as having a potential filament-crosslinking role.


Asunto(s)
Citoesqueleto/metabolismo , Filamentos Intermedios/genética , Queratinas/genética , Lagartos/genética , Secuencia de Aminoácidos , Animales , Cisteína/química , Cisteína/genética , Cisteína/metabolismo , Epidermis/metabolismo , Epitelio/metabolismo , Glicina/química , Glicina/genética , Glicina/metabolismo , Filamentos Intermedios/química , Filamentos Intermedios/metabolismo , Queratinas/química , Queratinas/metabolismo , Lagartos/clasificación , Lagartos/metabolismo , Familia de Multigenes/genética , Prolina/química , Prolina/genética , Prolina/metabolismo , Homología de Secuencia de Aminoácido , Especificidad de la Especie
12.
J Struct Biol ; 213(1): 107706, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33577903

RESUMEN

Determination of the sequences of the keratin intermediate filament chains in tuatara has shown that these are closely akin to the α-keratins in human and other vertebrates, especially in the central, coiled-coil rod region. The domain lengths within the rod are preserved exactly, both Type I and Type II chains have been recognised, and sequence identity/homology exists between their respective chains. Nonetheless, there are characteristic differences in amino acid composition and sequence between their respective head (N-terminal) domains and their tail (C-terminal) domains, though some similarities are retained. Further, there is evidence of tandem repeats of a variety of lengths in the tuatara heads and tails indicative of sequence duplication events. These are not evident in human α-keratins and would therefore have implications for the physical attributes of the tissues in the two species. Multiple families of keratin-associated proteins that are ultra-high cysteine-rich or glycine + tyrosine-rich in human and other species do not have direct equivalents in the tuatara. Although high-sulphur proteins are present in tuatara the cysteine residue contents are significantly lower than in human. Further, no sequence homologies between the HS proteins in the two species have been found, thereby casting considerable doubt as to whether any matrix-forming high-sulphur proteins exist in tuatara. These observations may be correlated with the numerous cysteine-rich ß-keratins (corneous ß-proteins) that are present in tuatara, but which are conspicuously absent in mammals.


Asunto(s)
Filamentos Intermedios/metabolismo , Queratinas/metabolismo , Reptiles/metabolismo , Secuencia de Aminoácidos , Aminoácidos/metabolismo , Animales , Evolución Biológica , Proteínas del Citoesqueleto/metabolismo , Humanos , Homología de Secuencia de Aminoácido
13.
Int J Cancer ; 148(3): 572-583, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-32683688

RESUMEN

Survivors of childhood cancer treated with cranial irradiation are at risk of cerebrovascular disease (CVD), but the risks beyond age 50 are unknown. In all, 13457 survivors of childhood cancer included in the population-based British Childhood Cancer Survivor Study cohort were linked to Hospital Episode Statistics data for England. Risk of CVD related hospitalisation was quantified by standardised hospitalisation ratios (SHRs), absolute excess risks and cumulative incidence. Overall, 315 (2.3%) survivors had been hospitalised at least once for CVD with a 4-fold risk compared to that expected (95% confidence interval [CI]: 3.7-4.3). Survivors of a central nervous system (CNS) tumour and leukaemia treated with cranial irradiation were at greatest risk of CVD (SHR = 15.6, 95% CI: 14.0-17.4; SHR = 5.4; 95% CI: 4.5-6.5, respectively). Beyond age 60, on average, 3.1% of CNS tumour survivors treated with cranial irradiation were hospitalised annually for CVD (0.4% general population). Cumulative incidence of CVD increased from 16.0% at age 50 to 26.0% at age 65 (general population: 1.4-4.2%). In conclusion, among CNS tumour survivors treated with cranial irradiation, the risk of CVD continues to increase substantially beyond age 50 up to at least age 65. Such survivors should be: counselled regarding this risk; regularly monitored for hypertension, dyslipidaemia and diabetes; advised on life-style risk behaviours. Future research should include the recall for counselling and brain MRI to identify subgroups that could benefit from pharmacological or surgical intervention and establishment of a case-control study to comprehensively determine risk-factors for CVD.


Asunto(s)
Supervivientes de Cáncer , Neoplasias del Sistema Nervioso Central/radioterapia , Trastornos Cerebrovasculares/epidemiología , Leucemia/radioterapia , Radioterapia/efectos adversos , Adulto , Adultos Sobrevivientes de Eventos Adversos Infantiles , Factores de Edad , Anciano , Estudios de Casos y Controles , Trastornos Cerebrovasculares/etiología , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Reino Unido/epidemiología , Adulto Joven
14.
Mol Microbiol ; 113(6): 1101-1121, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32022309

RESUMEN

Although lipid signaling has been shown to serve crucial roles in mammals and plants, little is known about this process in filamentous fungi. Here we analyze the contribution of phospholipase D (PLD) and its product phosphatidic acid (PA) in hyphal morphogenesis and growth of Epichloë festucae and Neurospora crassa, and in the establishment of a symbiotic interaction between E. festucae and Lolium perenne. Growth of E. festucae and N. crassa PLD deletion strains in axenic culture, and for E. festucae in association with L. perenne, were analyzed by light-, confocal- and electron microscopy. Changes in PA distribution were analyzed in E. festucae using a PA biosensor and the impact of these changes on the endocytic recycling and superoxide production investigated. We found that E. festucae PldB, and the N. crassa ortholog, PLA-7, are required for polarized growth and cell fusion and contribute to ascospore development, whereas PldA/PLA-8 are dispensable for these functions. Exogenous addition of PA rescues the cell-fusion phenotype in E. festucae. PldB is also crucial for E. festucae to establish a symbiotic association with L. perenne. This study identifies a new component of the cell-cell communication and cell fusion signaling network for hyphal morphogenesis and growth of filamentous fungi.


Asunto(s)
Epichloe/crecimiento & desarrollo , Lolium/microbiología , Neurospora crassa/crecimiento & desarrollo , Ácidos Fosfatidicos/metabolismo , Fosfolipasa D/metabolismo , Técnicas Biosensibles , Comunicación Celular , Fusión Celular , Epichloe/fisiología , Eliminación de Gen , Regulación Fúngica de la Expresión Génica/genética , Hifa/crecimiento & desarrollo , Lolium/fisiología , Fosfatidilcolinas/metabolismo , Transducción de Señal/fisiología , Esporas Fúngicas/crecimiento & desarrollo , Superóxidos/metabolismo , Simbiosis/fisiología
15.
Environ Microbiol ; 23(4): 2116-2131, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33350014

RESUMEN

Recent studies have identified key genes that control the symbiotic interaction between Epichloë festucae and Lolium perenne. Here we report on the identification of specific E. festucae genes that control host infection. Deletion of setB, which encodes a homologue of the H3K36 histone methyltransferase Set2/KMT3, reduced histone H3K36 trimethylation and led to severe defects in colony growth and hyphal development. The E. festucae ΔclrD mutant, which lacks the gene encoding the homologue of the H3K9 methyltransferase KMT1, displays similar developmental defects. Both mutants are completely defective in their ability to infect L. perenne. Alleles that complement the culture and plant phenotypes of both mutants also complement the histone methylation defects. Co-inoculation of either ΔsetB or ΔclrD with the wild-type strain enables these mutants to colonize the host. However, successful colonization by the mutants resulted in death or stunting of the host plant. Transcriptome analysis at the early infection stage identified four fungal candidate genes, three of which encode small-secreted proteins, that are differentially regulated in these mutants compared to wild type. Deletion of crbA, which encodes a putative carbohydrate binding protein, resulted in significantly reduced host infection rates by E. festucae.


Asunto(s)
Epichloe , Epichloe/genética , Epichloe/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Histonas/genética , Metiltransferasas/genética , Poaceae , Simbiosis/genética
16.
PLoS Genet ; 14(10): e1007467, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30356280

RESUMEN

Structural features of genomes, including the three-dimensional arrangement of DNA in the nucleus, are increasingly seen as key contributors to the regulation of gene expression. However, studies on how genome structure and nuclear organisation influence transcription have so far been limited to a handful of model species. This narrow focus limits our ability to draw general conclusions about the ways in which three-dimensional structures are encoded, and to integrate information from three-dimensional data to address a broader gamut of biological questions. Here, we generate a complete and gapless genome sequence for the filamentous fungus, Epichloë festucae. We use Hi-C data to examine the three-dimensional organisation of the genome, and RNA-seq data to investigate how Epichloë genome structure contributes to the suite of transcriptional changes needed to maintain symbiotic relationships with the grass host. Our results reveal a genome in which very repeat-rich blocks of DNA with discrete boundaries are interspersed by gene-rich sequences that are almost repeat-free. In contrast to other species reported to date, the three-dimensional structure of the genome is anchored by these repeat blocks, which act to isolate transcription in neighbouring gene-rich regions. Genes that are differentially expressed in planta are enriched near the boundaries of these repeat-rich blocks, suggesting that their three-dimensional orientation partly encodes and regulates the symbiotic relationship formed by this organism.


Asunto(s)
ADN de Hongos/genética , Epichloe/genética , Regulación Fúngica de la Expresión Génica , Genoma Fúngico/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Secuencia Rica en At/genética , ADN de Hongos/química , Proteínas Fúngicas/genética , Secuencia Rica en GC/genética , Perfilación de la Expresión Génica/métodos , Hifa/genética , Análisis de Secuencia de ADN/métodos , Simbiosis/genética
17.
Gut ; 2020 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-33139271

RESUMEN

BACKGROUND: Survivors of childhood cancer are at risk of subsequent primary neoplasms (SPNs), but the risk of developing specific digestive SPNs beyond age 40 years remains uncertain. We investigated risks of specific digestive SPNs within the largest available cohort worldwide. METHODS: The PanCareSurFup cohort includes 69 460 five-year survivors of childhood cancer from 12 countries in Europe. Risks of digestive SPNs were quantified using standardised incidence ratios (SIRs), absolute excess risks and cumulative incidence. RESULTS: 427 digestive SPNs (214 colorectal, 62 liver, 48 stomach, 44 pancreas, 59 other) were diagnosed in 413 survivors. Wilms tumour (WT) and Hodgkin lymphoma (HL) survivors were at greatest risk (SIR 12.1; 95% CI 9.6 to 15.1; SIR 7.3; 95% CI 5.9 to 9.0, respectively). The cumulative incidence increased the most steeply with increasing age for WT survivors, reaching 7.4% by age 55% and 9.6% by age 60 years (1.0% expected based on general population rates). Regarding colorectal SPNs, WT and HL survivors were at greatest risk; both seven times that expected. By age 55 years, 2.3% of both WT (95% CI 1.4 to 3.9) and HL (95% CI 1.6 to 3.2) survivors had developed a colorectal SPN-comparable to the risk among members of the general population with at least two first-degree relatives affected. CONCLUSIONS: Colonoscopy surveillance before age 55 is recommended in many European countries for individuals with a family history of colorectal cancer, but not for WT and HL survivors despite a comparable risk profile. Clinically, serious consideration should be given to the implementation of colonoscopy surveillance while further evaluation of its benefits, harms and cost-effectiveness in WT and HL survivors is undertaken.

18.
Mol Plant Microbe Interact ; 33(2): 149-152, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31631770

RESUMEN

Pecan scab, caused by Venturia effusa, is a devastating disease of pecan (Carya illinoinensis), which results in economic losses on susceptible cultivars throughout the southeastern United States. To enhance our understanding of pathogenicity in V. effusa, we have generated a complete telomere-to-telomere reference genome of V. effusa isolate FRT5LL7-Albino. By combining Illumina MiSeq and Oxford Nanopore MinION data, we assembled a 45.2-Mb genome represented by 20 chromosomes and containing 10,820 putative genes, of which 7,619 have at least one functional annotation. The likely causative mutation of the albino phenotype was identified as a single base insertion and a resulting frameshift in the gene encoding the polyketide synthase ALM1. This genome represents the first full chromosome-level assembly of any Venturia sp.


Asunto(s)
Ascomicetos , Carya , Cromosomas Fúngicos , Ascomicetos/genética , Carya/microbiología , Cromosomas Fúngicos/genética , Enfermedades de las Plantas/microbiología
19.
Arch Insect Biochem Physiol ; 105(4): e21754, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33124702

RESUMEN

Species in the fungal genus Beauveria are pathogens of invertebrates and have been commonly used as the active agent in biopesticides. After many decades with few species described, recent molecular approaches to classification have led to over 25 species now delimited. Little attention has been given to the mitochondrial genomes of Beauveria but better understanding may led to insights into the nature of species and evolution in this important genus. In this study, we sequenced the mitochondrial genomes of four new strains belonging to Beauveria bassiana, Beauveria caledonica and Beauveria malawiensis, and compared them to existing mitochondrial sequences of related fungi. The mitochondrial genomes of Beauveria ranged widely from 28,806 to 44,135 base pairs, with intron insertions accounting for most size variation and up to 39% (B. malawiensis) of the mitochondrial length due to introns in genes. Gene order of the common mitochondrial genes did not vary among the Beauveria sequences, but variation was observed in the number of transfer ribonucleic acid genes. Although phylogenetic analysis using whole mitochondrial genomes showed, unsurprisingly, that B. bassiana isolates were the most closely related to each other, mitochondrial codon usage suggested that some B. bassiana isolates were more similar to B. malawiensis and B. caledonica than the other B. bassiana isolates analyzed.


Asunto(s)
Beauveria/clasificación , Beauveria/genética , Mitocondrias/genética , Evolución Molecular , Genoma Fúngico , Filogenia , Análisis de Secuencia de ADN
20.
Lancet Oncol ; 20(4): 531-545, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30797674

RESUMEN

BACKGROUND: Few studies have investigated the risks of subsequent primary neoplasms after adolescent and young adult (AYA) cancer. We investigated the risks of specific subsequent primary neoplasms after each of 16 types of AYA cancer. METHODS: The Teenage and Young Adult Cancer Survivor Study is a population-based cohort of 200 945 survivors of cancer diagnosed when aged 15-39 years in England and Wales from Jan 1, 1971, to Dec 31, 2006. The cohort was established using cancer registrations from the Office for National Statistics and the Welsh Cancer registry. Follow-up was from 5-year survival until the first occurrence of death, emigration, or study end date (Dec 31, 2012). In this analysis, we focus on the risk of specific subsequent primary neoplasms after 16 types of AYA cancer: breast; cervical; testicular; Hodgkin lymphoma (female); Hodgkin lymphoma (male); melanoma; CNS (intracranial); colorectal; non-Hodgkin lymphoma; thyroid; soft-tissue sarcoma; ovarian; bladder; other female genital; leukaemia; and head and neck cancer. We report absolute excess risks (AERs; per 10 000 person-years) and cumulative incidence of specific types of subsequent primary neoplasm after each type of AYA cancer. FINDINGS: During the 2 631 326 person-years of follow-up (median follow-up 16·8 years, IQR 10·5-25·2), 12 321 subsequent primary neoplasms were diagnosed in 11 565 survivors, most frequently among survivors of breast cancer, cervical cancer, testicular cancer, and Hodgkin lymphoma. AERs of any subsequent primary neoplasms were 19·5 per 10 000 person-years (95% CI 17·4-21·5) in survivors of breast cancer, 10·2 (8·0-12·4) in survivors of cervical cancer, 18·9 (16·6-21·1) in survivors of testicular cancer, 55·7 (50·4-61·1) in female survivors of Hodgkin lymphoma, and 29·9 (26·3-33·6) in male survivors of Hodgkin lymphoma. The cumulative incidence of all subsequent primary neoplasms 35 years after diagnosis was 11·9% (95% CI 11·3-12·6) in survivors of breast cancer, 15·8% (14·8-16·7) in survivors of cervical cancer, 20·2% (18·9-21·5) in survivors of testicular cancer, 26·6% (24·7-28·6) in female survivors of Hodgkin lymphoma, and 16·5% (15·2-18·0) in male survivors of Hodgkin lymphoma. In patients who had survived at least 30 years from diagnosis of cervical cancer, testicular cancer, Hodgkin lymphoma in women, breast cancer, and Hodgkin lymphoma in men, we identified a small number of specific subsequent primary neoplasms that account for 82%, 61%, 58%, 45%, and 41% of the total excess number of neoplasms, respectively. Lung cancer accounted for a notable proportion of the excess number of neoplasms across all AYA groups investigated. INTERPRETATION: Our finding that a small number of specific subsequent primary neoplasms account for a large percentage of the total excess number of neoplasms in long-term survivors of cervical, breast, and testicular cancer, and Hodgkin lymphoma provides an evidence base to inform priorities for clinical long-term follow-up. The prominence of lung cancer after each of these AYA cancers indicates the need for further work aimed at preventing and reducing the burden of this cancer in future survivors of AYA cancer. FUNDING: Cancer Research UK, National Institute for Health Research, Academy of Medical Sciences, and Children with Cancer UK.


Asunto(s)
Supervivientes de Cáncer/estadística & datos numéricos , Neoplasias Primarias Secundarias/epidemiología , Adolescente , Estudios de Cohortes , Inglaterra/epidemiología , Humanos , Incidencia , Neoplasias Primarias Secundarias/diagnóstico , Neoplasias Primarias Secundarias/prevención & control , Sistema de Registros/estadística & datos numéricos , Factores de Riesgo , Gales/epidemiología , Adulto Joven
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