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1.
Sci Rep ; 13(1): 9822, 2023 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-37330541

RESUMO

Biomarkers to identify women at risk of cervical cancer among those with high-risk HPV infection (hrHPV+) are needed. Deregulated expression of microRNAs (miRNAs) contributes to hrHPV-induced cervical carcinogenesis. We aimed at identifying miRNAs with the capacity to distinguish high (CIN2+) and low (≤ CIN1) grade cervical lesions. We sequenced miRNA libraries from Formalin-Fixed Paraffin-Embedded (FFPE) tissues from women with CIN2+ (n = 10) and age-matched women with ≤ CIN1 (n = 10), randomly and retrospectively selected from a trial that followed women for 24 months after a hrHPV+ test at the screening visit. Five miRNAs differentially expressed were validated by RT-qPCR in an independent set of FFPE tissues with a reviewed diagnosis of CIN2+ (n = 105) and ≤ CIN1 (n = 105). The Ingenuity Pathway Analysis (IPA) was conducted to identify mRNAs inversely correlated with the top 25 differentially expressed miRNAs. Inverse correlations with 401 unique mRNA targets were identified for fourteen of the top 25 differentially expressed miRNAs. Eleven of these miRNAs targeted 26 proteins of pathways deregulated by HPV E6 and E7 oncoproteins and two of them, miR-143-5p and miR-29a-3p, predicted CIN2+ and CIN3+ in the independent validation by RT-qPCR of FFPE tissues from hrHPV-positive women.


Assuntos
MicroRNAs , Infecções por Papillomavirus , Lesões Pré-Cancerosas , Neoplasias do Colo do Útero , Humanos , Feminino , MicroRNAs/genética , MicroRNAs/metabolismo , Papillomavirus Humano , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/genética , Biomarcadores , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/genética , Papillomaviridae/genética , Papillomaviridae/metabolismo
2.
New Phytol ; 235(5): 1944-1956, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35657639

RESUMO

From its origins in Australia, Eucalyptus grandis has spread to every continent, except Antarctica, as a wood crop. It has been cultivated and bred for over 100 yr in places such as South Africa. Unlike most annual crops and fruit trees, domestication of E. grandis is still in its infancy, representing a unique opportunity to interrogate the genomic consequences of artificial selection early in the domestication process. To determine how a century of artificial selection has changed the genome of E. grandis, we generated single nucleotide polymorphism genotypes for 1080 individuals from three advanced South African breeding programmes using the EUChip60K chip, and investigated population structure and genome-wide differentiation patterns relative to wild progenitors. Breeding and wild populations appeared genetically distinct. We found genomic evidence of evolutionary processes known to have occurred in other plant domesticates, including interspecific introgression and intraspecific infusion from wild material. Furthermore, we found genomic regions with increased linkage disequilibrium and genetic differentiation, putatively representing early soft sweeps of selection. This is, to our knowledge, the first study of genomic signatures of domestication in a timber species looking beyond the first few generations of cultivation. Our findings highlight the importance of intra- and interspecific hybridization during early domestication.


Assuntos
Domesticação , Genoma de Planta , Genômica , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único/genética , Seleção Genética , Madeira/genética
3.
Mol Ecol Resour ; 22(2): 695-710, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34383377

RESUMO

We performed gene and genome targeted SNP discovery towards the development of a genome-wide, multispecies genotyping array for tropical pines. Pooled RNA-seq data from shoots of seedlings from five tropical pine species was used to identify transcript-based SNPs resulting in 1.3 million candidate Affymetrix SNP probe sets. In addition, we used a custom 40 K probe set to perform capture-seq in pooled DNA from 81 provenances representing the natural ranges of six tropical pine species in Mexico and Central America resulting in 563 K candidate SNP probe sets. Altogether, 300 K RNA-seq (72%) and 120 K capture-seq (28%) derived SNP probe sets were tiled on a 420 K screening array that was used to genotype 576 trees representing the 81 provenances and commercial breeding material. Based on the screening array results, 50 K SNPs were selected for commercial SNP array production including 20 K polymorphic SNPs for P. patula, P. tecunumanii, P. oocarpa and P. caribaea, 15 K for P. greggii and P. maximinoi, 13 K for P. elliottii and 8K for P. pseudostrobus. We included 9.7 K ancestry informative SNPs that will be valuable for species and hybrid discrimination. Of the 50 K SNP markers, 25% are polymorphic in only one species, while 75% are shared by two or more species. The Pitro50K SNP chip will be useful for population genomics and molecular breeding in this group of pine species that, together with their hybrids, represent the majority of fast-growing tropical and subtropical pine plantations globally.


Assuntos
Pinus , Árvores , Genoma , Genótipo , Pinus/genética , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único , Árvores/genética
4.
G3 (Bethesda) ; 10(8): 2683-2696, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32546502

RESUMO

Understanding the consequences of local adaptation at the genomic diversity is a central goal in evolutionary genetics of natural populations. In species with large continuous geographical distributions the phenotypic signal of local adaptation is frequently clear, but the genetic basis often remains elusive. We examined the patterns of genetic diversity in Pinus sylvestris, a keystone species in many Eurasian ecosystems with a huge distribution range and decades of forestry research showing that it is locally adapted to the vast range of environmental conditions. Making P. sylvestris an even more attractive subject of local adaptation study, population structure has been shown to be weak previously and in this study. However, little is known about the molecular genetic basis of adaptation, as the massive size of gymnosperm genomes has prevented large scale genomic surveys. We generated a both geographically and genomically extensive dataset using a targeted sequencing approach. By applying divergence-based and landscape genomics methods we identified several loci contributing to local adaptation, but only few with large allele frequency changes across latitude. We also discovered a very large (ca. 300 Mbp) putative inversion potentially under selection, which to our knowledge is the first such discovery in conifers. Our results call for more detailed analysis of structural variation in relation to genomic basis of local adaptation, emphasize the lack of large effect loci contributing to local adaptation in the coding regions and thus point out the need for more attention toward multi-locus analysis of polygenic adaptation.


Assuntos
Pinus sylvestris , Pinus , Adaptação Fisiológica/genética , Ecossistema , Variação Genética , Genética Populacional , Genômica , Pinus sylvestris/genética , Seleção Genética
5.
Genome Biol Evol ; 11(2): 508-520, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30689841

RESUMO

Loblolly pine (Pinus taeda) and slash pine (Pinus elliottii) are ecologically and economically important pine species that dominate many forest ecosystems in the southern United States, but like all conifers, the study of their genetic diversity and demographic history has been hampered by their large genome size. A small number of studies mainly based on candidate-gene sequencing have been reported for P. taeda to date, whereas none are available for P. elliottii. Targeted exome resequencing has recently enabled population genomics studies for conifers, approach used here to assess genomic diversity, signatures of selection, population structure, and demographic history of P. elliottii and P. taeda. Extensive similarities were revealed between these species: both species feature rapid linkage disequilibrium decay and high levels of genetic diversity. Moreover, genome-wide positive correlations for measures of genetic diversity between the species were also observed, likely due to shared structural genomic constraints. Also, positive selection appears to be targeting a common set of genes in both pines. Demographic history differs between both species, with only P. taeda being affected by a dramatic bottleneck during the last glacial period. The ability of P. taeda to recover from a dramatic reduction in population size while still retaining high levels of genetic diversity shows promise for other pines facing environmental stressors associated with climate change, indicating that these too may be able to adapt successfully to new future conditions even after a drastic population size contraction.


Assuntos
Evolução Biológica , Variação Genética , Pinus taeda/genética , Seleção Genética , Simulação por Computador , Desequilíbrio de Ligação , Óvulo Vegetal/química , Dinâmica Populacional
6.
Plant Cell Environ ; 41(8): 1840-1851, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29710389

RESUMO

Leptocybe invasa is an insect pest causing gall formation on oviposited shoot tips and leaves of Eucalyptus trees leading to leaf deformation, stunting, and death in severe cases. We previously observed different constitutive and induced terpenes, plant specialized metabolites that may act as attractants or repellents to insects, in a resistant and susceptible clone of Eucalyptus challenged with L. invasa. We tested the hypothesis that specific terpenes are associated with pest resistance in a Eucalyptus grandis half-sib population. Insect damage was scored over 2 infestation cycles, and leaves were harvested for near-infrared reflectance (NIR) and terpene measurements. We used Bayesian model averaging for terpene selection and obtained partial least squares NIR models to predict terpene content and L. invasa infestation damage. In our optimal model, 29% of the phenotypic variation could be explained by 7 terpenes, and the monoterpene combination, limonene, α-terpineol, and 1,8-cineole, could be predicted with an NIR prediction ability of  .67. Bayesian model averaging supported α-pinene, γ-terpinene, and iso-pinocarveol as important for predicting L. invasa infestation. Susceptibility was associated with increased γ-terpinene and α-pinene, which may act as a pest attractant, whereas reduced susceptibility was associated with iso-pinocarveol, which may act to recruit parasitoids or have direct toxic effects.


Assuntos
Eucalyptus/parasitologia , Tumores de Planta/parasitologia , Terpenos/metabolismo , Vespas , Animais , Resistência à Doença , Eucalyptus/imunologia , Eucalyptus/metabolismo , Folhas de Planta/parasitologia , Brotos de Planta/parasitologia , Espectroscopia de Luz Próxima ao Infravermelho
7.
Surg Neurol Int ; 8: 168, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28840072

RESUMO

BACKGROUND: Neurocysticercosis (NCC) is a common parasitic infection of the central nervous system, caused by the tapeworm Taenia solium. It is endemic to certain parts of the world, including Central America, South America, Asia, and Africa. The racemose form, characterized by extraparenchymal location, increased morbidity and mortality, and large loculated cystic lesions, is rarely seen in industrialized countries, such as the United States. The management of racemose neurocysticercosis (RNCC) differs from that of the typical parenchymal variant. The ideal course of treatment is debated by experts, but typically includes either surgical intervention with subsequent medical therapy or medical therapy alone. CASE DESCRIPTION: We present the case of a 34-year-old male diagnosed with RNCC and treated successfully with surgical cyst drainage, resection, and subsequent medical therapy. CONCLUSION: Currently, no standardized evidence-based protocol exists that dictate appropriate treatment for extraparenchymal or racemose NCC. We present a case of RNCC treated successfully with surgical and medical intervention. Further research encompassing well-designed clinical trials is necessary to delineate appropriate and standardized protocols for treatment of this disease.

8.
Mol Endocrinol ; 17(11): 2268-82, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12907754

RESUMO

Prolactin (PRL) stimulates breast cancer cell proliferation; however, the involvement of PRL-activated signaling molecules in cell proliferation is not fully established. Here we studied the role of c-Src on PRL-stimulated proliferation of T47D and MCF7 breast cancer cells. We initially observed that PRL-dependent activation of focal adhesion kinase (Fak), Erk1/2, and cell proliferation was mediated by c-Src in T47D cells, because expression of a dominant-negative form of c-Src (SrcDM, K295A/Y527F) blocked the PRL-dependent effects. The Src inhibitor PP1 abrogated PRL-dependent in vivo activation of Fak, Erk1/2, p70S6K, and Akt and the proliferation of T47D and MCF7 cells; Janus kinase 2 (Jak2) activation was not affected. However, in vitro, Fak and Jak2 kinases were not directly inhibited by PP1, demonstrating the effect of PP1 on c-Src kinase as an upstream activator of Fak. Expression of Fak mutant Y397F abrogated PRL-dependent activation of Fak, Erk1/2, and thymidine incorporation, but had no effect on p70S6K and Akt kinases. MAPK kinase 1/2 (Mek1/2) inhibitor PD184352 blocked PRL-induced stimulation of Erk1/2 and cell proliferation; however, p70S6K and Akt activation were unaffected. The phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 abolished cell proliferation and activation of p70S6K and Akt; however, PRL-dependent activation of Erk1/2 was not modified. Moreover, we show that both c-Src/PI3K and c-Src/Fak/Erk1/2 pathways are involved in the up-regulation of c-myc and cyclin d1 expression mediated by PRL. The previous findings suggest the existence of two PRL-dependent signaling cascades, initiated by the c-Src-mediated activation of Fak/Erk1/2 and PI3K pathways that, subsequently, control the expression of c-Myc and cyclin D1 and the proliferation of T47D and MCF7 breast cancer cells.


Assuntos
Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Prolactina/farmacologia , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ciclina D1/metabolismo , Ativação Enzimática/efeitos dos fármacos , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Humanos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Fosfoinositídeo-3 Quinase , Fosfotirosina/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/antagonistas & inibidores , Ovinos , Transdução de Sinais/efeitos dos fármacos
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