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1.
Sci Rep ; 14(1): 8271, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594555

RESUMO

Community-acquired Pneumonia (CAP) guidelines generally recommend to admit patients with moderate-to-severe CAP and start treatment with intravenous antibiotics. This study aims to explore the clinical outcomes of oral antibiotics in patients with moderate-to-severe CAP. We performed a nested cohort study of an observational study including all adult patients presenting to the emergency department of the Haga Teaching Hospital, the Netherlands, between April 2019 and May 2020, who had a blood culture drawn. We conducted propensity score matching with logistic and linear regression analysis to compare patients with moderate-to-severe CAP (Pneumonia Severity Index class III-V) treated with oral antibiotics to patients treated with intravenous antibiotics. Outcomes were 30-day mortality, intensive care unit admission, readmission, length of stay (LOS) and length of antibiotic treatment. Of the original 314 patients, 71 orally treated patients were matched with 102 intravenously treated patients. The mean age was 73 years and 58% were male. We found no significant differences in outcomes between the oral and intravenous group, except for an increased LOS of + 2.6 days (95% confidence interval 1.2-4.0, p value < 0.001) in those treated intravenously. We conclude that oral antibiotics might be a safe and effective treatment for moderate-to-severe CAP for selected patients based on the clinical judgement of the attending physician.


Assuntos
Infecções Comunitárias Adquiridas , Pneumonia , Adulto , Humanos , Masculino , Idoso , Feminino , Antibacterianos/uso terapêutico , Estudos de Coortes , Pontuação de Propensão , Pneumonia/tratamento farmacológico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Tempo de Internação , Estudos Retrospectivos
2.
J Clin Invest ; 132(5)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35229724

RESUMO

GPIHBP1, an endothelial cell (EC) protein, captures lipoprotein lipase (LPL) within the interstitial spaces (where it is secreted by myocytes and adipocytes) and transports it across ECs to its site of action in the capillary lumen. GPIHBP1's 3-fingered LU domain is required for LPL binding, but the function of its acidic domain (AD) has remained unclear. We created mutant mice lacking the AD and found severe hypertriglyceridemia. As expected, the mutant GPIHBP1 retained the capacity to bind LPL. Unexpectedly, however, most of the GPIHBP1 and LPL in the mutant mice was located on the abluminal surface of ECs (explaining the hypertriglyceridemia). The GPIHBP1-bound LPL was trapped on the abluminal surface of ECs by electrostatic interactions between the large basic patch on the surface of LPL and negatively charged heparan sulfate proteoglycans (HSPGs) on the surface of ECs. GPIHBP1 trafficking across ECs in the mutant mice was normalized by disrupting LPL-HSPG electrostatic interactions with either heparin or an AD peptide. Thus, GPIHBP1's AD plays a crucial function in plasma triglyceride metabolism; it sheathes LPL's basic patch on the abluminal surface of ECs, thereby preventing LPL-HSPG interactions and freeing GPIHBP1-LPL complexes to move across ECs to the capillary lumen.


Assuntos
Lipase Lipoproteica , Receptores de Lipoproteínas , Animais , Capilares/metabolismo , Células Endoteliais/metabolismo , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Camundongos , Receptores de Lipoproteínas/química , Receptores de Lipoproteínas/genética , Receptores de Lipoproteínas/metabolismo , Eletricidade Estática
3.
Artigo em Inglês | MEDLINE | ID: mdl-32266160

RESUMO

Background: Several studies suggested an important role of the gut microbiota in the pathophysiology of neurological disorders, implying that alteration of the gut microbiota might serve as a treatment strategy. Fecal microbiota transplantation (FMT) is currently the most effective gut microbiota intervention and an accepted treatment for recurrent Clostridioides difficile infections. To evaluate indications of FMT for patients with neurological disorders, we summarized the available literature on FMT. In addition, we provide suggestions for future directions. Methods: In July 2019, five main databases were searched for studies and case descriptions on FMT in neurological disorders in humans or animal models. In addition, the ClinicalTrials.gov website was consulted for registered planned and ongoing trials. Results: Of 541 identified studies, 34 were included in the analysis. Clinical trials with FMT have been performed in patients with autism spectrum disorder and showed beneficial effects on neurological symptoms. For multiple sclerosis and Parkinson's disease, several animal studies suggested a positive effect of FMT, supported by some human case reports. For epilepsy, Tourette syndrome, and diabetic neuropathy some studies suggested a beneficial effect of FMT, but evidence was restricted to case reports and limited numbers of animal studies. For stroke, Alzheimer's disease and Guillain-Barré syndrome only studies with animal models were identified. These studies suggested a potential beneficial effect of healthy donor FMT. In contrast, one study with an animal model for stroke showed increased mortality after FMT. For Guillain-Barré only one study was identified. Whether positive findings from animal studies can be confirmed in the treatment of human diseases awaits to be seen. Several trials with FMT as treatment for the above mentioned neurological disorders are planned or ongoing, as well as for amyotrophic lateral sclerosis. Conclusions: Preliminary literature suggests that FMT may be a promising treatment option for several neurological disorders. However, available evidence is still scanty and some contrasting results were observed. A limited number of studies in humans have been performed or are ongoing, while for some disorders only animal experiments have been conducted. Large double-blinded randomized controlled trials are needed to further elucidate the effect of FMT in neurological disorders.


Assuntos
Transtorno do Espectro Autista , Infecções por Clostridium , Microbioma Gastrointestinal , Doenças do Sistema Nervoso , Animais , Infecções por Clostridium/terapia , Transplante de Microbiota Fecal , Fezes , Humanos , Doenças do Sistema Nervoso/terapia , Resultado do Tratamento
4.
J Lipid Res ; 61(3): 413-421, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31941672

RESUMO

Zinc metallopeptidase STE24 (ZMPSTE24) is essential for the conversion of farnesyl-prelamin A to mature lamin A, a key component of the nuclear lamina. In the absence of ZMPSTE24, farnesyl-prelamin A accumulates in the nucleus and exerts toxicity, causing a variety of disease phenotypes. By ∼4 months of age, both male and female Zmpste24-/- mice manifest a near-complete loss of adipose tissue, but it has never been clear whether this phenotype is a direct consequence of farnesyl-prelamin A toxicity in adipocytes. To address this question, we generated a conditional knockout Zmpste24 allele and used it to create adipocyte-specific Zmpste24-knockout mice. To boost farnesyl-prelamin A levels, we bred in the "prelamin A-only" Lmna allele. Gene expression, immunoblotting, and immunohistochemistry experiments revealed that adipose tissue in these mice had decreased Zmpste24 expression along with strikingly increased accumulation of prelamin A. In male mice, Zmpste24 deficiency in adipocytes was accompanied by modest changes in adipose stores (an 11% decrease in body weight, a 23% decrease in body fat mass, and significantly smaller gonadal and inguinal white adipose depots). No changes in adipose stores were detected in female mice, likely because prelamin A expression in adipose tissue is lower in female mice. Zmpste24 deficiency in adipocytes did not alter the number of macrophages in adipose tissue, nor did it alter plasma levels of glucose, triglycerides, or fatty acids. We conclude that ZMPSTE24 deficiency in adipocytes, and the accompanying accumulation of farnesyl-prelamin A, reduces adipose tissue stores, but only modestly and only in male mice.


Assuntos
Tecido Adiposo/metabolismo , Lamina Tipo A/metabolismo , Proteínas de Membrana/metabolismo , Metaloendopeptidases/metabolismo , Tecido Adiposo/química , Alelos , Animais , Núcleo Celular/química , Núcleo Celular/metabolismo , Feminino , Masculino , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Metaloendopeptidases/deficiência , Metaloendopeptidases/genética , Camundongos , Camundongos Knockout , Camundongos Transgênicos
5.
Sci Total Environ ; 634: 1540-1553, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29710652

RESUMO

By the end of this century higher temperatures and significantly reduced rainfall are projected for the Brazilian North and Northeast (NE) regions due to Global Warming. This study examines the impact of these long-term rainfall changes on the Brazilian Northeast's hydroelectric production. Various studies that use different IPCC models are examined in order to determine the average rainfall reduction by the year 2100 in comparison to baseline data from the end of the 20th century. It was found that average annual rainfall in the NE region could decrease by approximately 25-50% depending on the emissions scenario. Analysis of historical rainfall data in the São Francisco basin during the last 57years already shows a decline of more than 25% from the 1961-90 long-term average. Moreover, average annual rainfall in the basin has been below its long-term average every year bar one since 1992. If this declining trend continues, rainfall reduction in the basin could be even more severe than the most pessimistic model projections. That is, the marked drop in average rainfall projected for 2100, based on the IPCC high emissions scenario, could actually eventuate before 2050. Due to the elasticity factor between rainfall and streamflow and because of increased amounts of irrigation in the São Francisco basin, the reduction in the NE's average hydroelectric production in the coming decades could be double the predicted decline in rainfall. Conversely, it is estimated that wind power potential in the Brazilian NE will increase substantially by 2100. Therefore both wind and solar power will need to be significantly exploited in order for the NE region to sustainably replace lost hydroelectric production.

7.
J Lipid Res ; 58(7): 1453-1461, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28476858

RESUMO

Mutation of conserved cysteines in proteins of the Ly6 family cause human disease-chylomicronemia in the case of glycosylphosphatidylinositol-anchored HDL binding protein 1 (GPIHBP1) and paroxysmal nocturnal hemoglobinuria in the case of CD59. A mutation in a conserved cysteine in CD59 prevented the protein from reaching the surface of blood cells. In contrast, mutation of conserved cysteines in human GPIHBP1 had little effect on GPIHBP1 trafficking to the surface of cultured CHO cells. The latter findings were somewhat surprising and raised questions about whether CHO cell studies accurately model the fate of mutant GPIHBP1 proteins in vivo. To explore this concern, we created mice harboring a GPIHBP1 cysteine mutation (p.C63Y). The p.C63Y mutation abolished the ability of mouse GPIHBP1 to bind LPL, resulting in severe chylomicronemia. The mutant GPIHBP1 was detectable by immunohistochemistry on the surface of endothelial cells, but the level of expression was ∼70% lower than in WT mice. The mutant GPIHBP1 protein in mouse tissues was predominantly monomeric. We conclude that mutation of a conserved cysteine in GPIHBP1 abolishes the ability of GPIHBP1 to bind LPL, resulting in mislocalization of LPL and severe chylomicronemia. The mutation reduced but did not eliminate GPIHBP1 on the surface of endothelial cells in vivo.


Assuntos
Sequência Conservada , Cisteína , Lipase Lipoproteica/metabolismo , Mutação , Receptores de Lipoproteínas/química , Receptores de Lipoproteínas/metabolismo , Animais , Células CHO , Cricetinae , Cricetulus , Feminino , Humanos , Lipase Lipoproteica/genética , Camundongos , Ligação Proteica/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Lipoproteínas/genética , Triglicerídeos/sangue
8.
Transgenic Res ; 26(2): 263-277, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27905063

RESUMO

The CRISPR/Cas9 system has rapidly advanced targeted genome editing technologies. However, its efficiency in targeting with constructs in mouse zygotes via homology directed repair (HDR) remains low. Here, we systematically explored optimal parameters for targeting constructs in mouse zygotes via HDR using mouse embryonic stem cells as a model system. We characterized several parameters, including single guide RNA cleavage activity and the length and symmetry of homology arms in the construct, and we compared the targeting efficiency between Cas9, Cas9nickase, and dCas9-FokI. We then applied the optimized conditions to zygotes, delivering Cas9 as either mRNA or protein. We found that Cas9 nucleo-protein complex promotes highly efficient, multiplexed targeting of circular constructs containing reporter genes and floxed exons. This approach allows for a one-step zygote injection procedure targeting multiple genes to generate conditional alleles via homologous recombination, and simultaneous knockout of corresponding genes in non-targeted alleles via non-homologous end joining.


Assuntos
Sistemas CRISPR-Cas/genética , Marcação de Genes/métodos , Recombinação Homóloga/genética , Alelos , Animais , Reparo do DNA por Junção de Extremidades/genética , Éxons , Camundongos , RNA Guia de Cinetoplastídeos/genética , RNA Mensageiro/genética , Zigoto/crescimento & desenvolvimento
9.
Genetics ; 204(4): 1613-1626, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27794028

RESUMO

Until very recently, complete characterization of the megagenomes of conifers has remained elusive. The diploid genome of sugar pine (Pinus lambertiana Dougl.) has a highly repetitive, 31 billion bp genome. It is the largest genome sequenced and assembled to date, and the first from the subgenus Strobus, or white pines, a group that is notable for having the largest genomes among the pines. The genome represents a unique opportunity to investigate genome "obesity" in conifers and white pines. Comparative analysis of P. lambertiana and P. taeda L. reveals new insights on the conservation, age, and diversity of the highly abundant transposable elements, the primary factor determining genome size. Like most North American white pines, the principal pathogen of P. lambertiana is white pine blister rust (Cronartium ribicola J.C. Fischer ex Raben.). Identification of candidate genes for resistance to this pathogen is of great ecological importance. The genome sequence afforded us the opportunity to make substantial progress on locating the major dominant gene for simple resistance hypersensitive response, Cr1 We describe new markers and gene annotation that are both tightly linked to Cr1 in a mapping population, and associated with Cr1 in unrelated sugar pine individuals sampled throughout the species' range, creating a solid foundation for future mapping. This genomic variation and annotated candidate genes characterized in our study of the Cr1 region are resources for future marker-assisted breeding efforts as well as for investigations of fundamental mechanisms of invasive disease and evolutionary response.


Assuntos
Genoma de Planta , Pinus/genética , Basidiomycota/patogenicidade , Elementos de DNA Transponíveis , Variação Genética , Tamanho do Genoma , Pinus/imunologia , Pinus/microbiologia , Imunidade Vegetal/genética
10.
Sci Rep ; 6: 31455, 2016 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-27530248

RESUMO

BAC transgenic mammalian systems offer an important platform for recapitulating human gene expression and disease modeling. While the larger body mass, and greater genetic and physiologic similarity to humans render rats well suited for reproducing human immune diseases and evaluating therapeutic strategies, difficulties of generating BAC transgenic rats have hindered progress. Thus, an efficient method for BAC transgenesis in rats would be valuable. Immunodeficient mice carrying a human SIRPA transgene have previously been shown to support improved human cell hematopoiesis. Here, we have generated for the first time, human SIRPA BAC transgenic rats, for which the gene is faithfully expressed, functionally active, and germline transmissible. To do this, human SIRPA BAC was modified with elements to work in coordination with genome engineering technologies-piggyBac, CRISPR/Cas9 or TALEN. Our findings show that piggyBac transposition is a more efficient approach than the classical BAC transgenesis, resulting in complete BAC integration with predictable end sequences, thereby permitting precise assessment of the integration site. Neither CRISPR/Cas9 nor TALEN increased BAC transgenesis. Therefore, an efficient generation of human SIRPA transgenic rats using piggyBac opens opportunities for expansion of humanized transgenic rat models in the future to advance biomedical research and therapeutic applications.


Assuntos
Antígenos de Diferenciação , Sistemas CRISPR-Cas , Cromossomos Artificiais Bacterianos/genética , Receptores Imunológicos , Transgenes , Zigoto , Animais , Antígenos de Diferenciação/biossíntese , Antígenos de Diferenciação/genética , Humanos , Camundongos , Camundongos Transgênicos , Ratos , Ratos Transgênicos , Receptores Imunológicos/biossíntese , Receptores Imunológicos/genética
11.
Neuron ; 90(3): 535-50, 2016 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-27112497

RESUMO

Hexanucleotide expansions in C9ORF72 are the most frequent genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. Disease mechanisms were evaluated in mice expressing C9ORF72 RNAs with up to 450 GGGGCC repeats or with one or both C9orf72 alleles inactivated. Chronic 50% reduction of C9ORF72 did not provoke disease, while its absence produced splenomegaly, enlarged lymph nodes, and mild social interaction deficits, but not motor dysfunction. Hexanucleotide expansions caused age-, repeat-length-, and expression-level-dependent accumulation of RNA foci and dipeptide-repeat proteins synthesized by AUG-independent translation, accompanied by loss of hippocampal neurons, increased anxiety, and impaired cognitive function. Single-dose injection of antisense oligonucleotides (ASOs) that target repeat-containing RNAs but preserve levels of mRNAs encoding C9ORF72 produced sustained reductions in RNA foci and dipeptide-repeat proteins, and ameliorated behavioral deficits. These efforts identify gain of toxicity as a central disease mechanism caused by repeat-expanded C9ORF72 and establish the feasibility of ASO-mediated therapy.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Demência Frontotemporal/tratamento farmacológico , Fatores de Troca do Nucleotídeo Guanina/genética , Oligonucleotídeos Antissenso/farmacologia , RNA/metabolismo , Esclerose Lateral Amiotrófica/genética , Animais , Proteína C9orf72 , Expansão das Repetições de DNA/genética , Demência Frontotemporal/genética , Camundongos Transgênicos , Neurônios/metabolismo , Oligonucleotídeos Antissenso/efeitos adversos , Oligonucleotídeos Antissenso/genética
12.
Nature ; 533(7602): 200-5, 2016 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-27088604

RESUMO

The whole-genome duplication 80 million years ago of the common ancestor of salmonids (salmonid-specific fourth vertebrate whole-genome duplication, Ss4R) provides unique opportunities to learn about the evolutionary fate of a duplicated vertebrate genome in 70 extant lineages. Here we present a high-quality genome assembly for Atlantic salmon (Salmo salar), and show that large genomic reorganizations, coinciding with bursts of transposon-mediated repeat expansions, were crucial for the post-Ss4R rediploidization process. Comparisons of duplicate gene expression patterns across a wide range of tissues with orthologous genes from a pre-Ss4R outgroup unexpectedly demonstrate far more instances of neofunctionalization than subfunctionalization. Surprisingly, we find that genes that were retained as duplicates after the teleost-specific whole-genome duplication 320 million years ago were not more likely to be retained after the Ss4R, and that the duplicate retention was not influenced to a great extent by the nature of the predicted protein interactions of the gene products. Finally, we demonstrate that the Atlantic salmon assembly can serve as a reference sequence for the study of other salmonids for a range of purposes.


Assuntos
Diploide , Evolução Molecular , Duplicação Gênica/genética , Genes Duplicados/genética , Genoma/genética , Salmo salar/genética , Animais , Elementos de DNA Transponíveis/genética , Feminino , Genômica , Masculino , Modelos Genéticos , Mutagênese/genética , Filogenia , Padrões de Referência , Salmo salar/classificação , Homologia de Sequência
13.
PLoS Genet ; 12(2): e1005691, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26839965

RESUMO

The unintended consequences of gene targeting in mouse models have not been thoroughly studied and a more systematic analysis is needed to understand the frequency and characteristics of off-target effects. Using RNA-seq, we evaluated targeted and neighboring gene expression in tissues from 44 homozygous mutants compared with C57BL/6N control mice. Two allele types were evaluated: 15 targeted trap mutations (TRAP); and 29 deletion alleles (DEL), usually a deletion between the translational start and the 3' UTR. Both targeting strategies insert a bacterial beta-galactosidase reporter (LacZ) and a neomycin resistance selection cassette. Evaluating transcription of genes in +/- 500 kb of flanking DNA around the targeted gene, we found up-regulated genes more frequently around DEL compared with TRAP alleles, however the frequency of alleles with local down-regulated genes flanking DEL and TRAP targets was similar. Down-regulated genes around both DEL and TRAP targets were found at a higher frequency than expected from a genome-wide survey. However, only around DEL targets were up-regulated genes found with a significantly higher frequency compared with genome-wide sampling. Transcriptome analysis confirms targeting in 97% of DEL alleles, but in only 47% of TRAP alleles probably due to non-functional splice variants, and some splicing around the gene trap. Local effects on gene expression are likely due to a number of factors including compensatory regulation, loss or disruption of intragenic regulatory elements, the exogenous promoter in the neo selection cassette, removal of insulating DNA in the DEL mutants, and local silencing due to disruption of normal chromatin organization or presence of exogenous DNA. An understanding of local position effects is important for understanding and interpreting any phenotype attributed to targeted gene mutations, or to spontaneous indels.


Assuntos
Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Marcação de Genes , Mutação/genética , Animais , Regulação para Baixo/genética , Deleção de Genes , Biblioteca Gênica , Genoma , Homozigoto , Camundongos Endogâmicos C57BL , Regulação para Cima/genética
14.
Neuron ; 88(5): 902-909, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26637797

RESUMO

A non-coding hexanucleotide repeat expansion in the C9ORF72 gene is the most common mutation associated with familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). To investigate the pathological role of C9ORF72 in these diseases, we generated a line of mice carrying a bacterial artificial chromosome containing exons 1 to 6 of the human C9ORF72 gene with approximately 500 repeats of the GGGGCC motif. The mice showed no overt behavioral phenotype but recapitulated distinctive histopathological features of C9ORF72 ALS/FTD, including sense and antisense intranuclear RNA foci and poly(glycine-proline) dipeptide repeat proteins. Finally, using an artificial microRNA that targets human C9ORF72 in cultures of primary cortical neurons from the C9BAC mice, we have attenuated expression of the C9BAC transgene and the poly(GP) dipeptides. The C9ORF72 BAC transgenic mice will be a valuable tool in the study of ALS/FTD pathobiology and therapy.


Assuntos
Esclerose Lateral Amiotrófica/genética , Expansão das Repetições de DNA/genética , Dipeptídeos/metabolismo , Modelos Animais de Doenças , Demência Frontotemporal/genética , Proteínas/genética , Fatores Etários , Esclerose Lateral Amiotrófica/mortalidade , Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Proteína C9orf72 , Células Cultivadas , Córtex Cerebral/citologia , Cromossomos Artificiais Bacterianos/genética , Cromossomos Artificiais Bacterianos/metabolismo , Dipeptídeos/genética , Demência Frontotemporal/mortalidade , Demência Frontotemporal/patologia , Demência Frontotemporal/fisiopatologia , Regulação da Expressão Gênica/genética , Genótipo , Humanos , Técnicas In Vitro , Camundongos Transgênicos , MicroRNAs/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/fisiologia
15.
PLoS One ; 10(8): e0134155, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26275310

RESUMO

Targeted mutations in mouse disrupt local chromatin structure and may lead to unanticipated local effects. We evaluated targeted gene promoter silencing in a group of six mutants carrying the tm1a Knockout Mouse Project allele containing both a LacZ reporter gene driven by the native promoter and a neo selection cassette. Messenger RNA levels of the reporter gene and targeted gene were assessed by qRT-PCR, and methylation of the promoter CpG islands and LacZ coding sequence were evaluated by sequencing of bisulfite-treated DNA. Mutants were stratified by LacZ staining into presumed Silenced and Expressed reporter genes. Silenced mutants had reduced relative quantities LacZ mRNA and greater CpG Island methylation compared with the Expressed mutant group. Within the silenced group, LacZ coding sequence methylation was significantly and positively correlated with CpG Island methylation, while promoter CpG methylation was only weakly correlated with LacZ gene mRNA. The results support the conclusion that there is promoter silencing in a subset of mutants carrying the tm1a allele. The features of targeted genes which promote local silencing when targeted remain unknown.


Assuntos
Ilhas de CpG , Metilação de DNA , Óperon Lac , Regiões Promotoras Genéticas , RNA Mensageiro/análise , Animais , Perfilação da Expressão Gênica/métodos , Inativação Gênica , Genes Reporter , Camundongos , Camundongos Knockout , Mutação
16.
Genome Res ; 25(4): 598-607, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25591789

RESUMO

Expression of the bacterial beta-galactosidase reporter gene (lacZ) in the vector used for the Knockout Mouse Project (KOMP) is driven by the endogenous promoter of the target gene. In tissues from KOMP mice, histochemical staining for LacZ enzyme activity can be used to determine gene expression patterns. With this technique, we have produced a comprehensive resource of gene expression using both whole mount (WM) and frozen section (FS) LacZ staining in 313 unique KOMP mutant mouse lines. Of these, ∼ 80% of mutants showed specific staining in one or more tissues, while ∼ 20% showed no specific staining, ∼ 13% had staining in only one tissue, and ∼ 25% had staining in >6 tissues. The highest frequency of specific staining occurred in the brain (∼ 50%), male gonads (42%), and kidney (39%). The WM method was useful for rapidly identifying whole organ and some substructure staining, while the FS method often revealed substructure and cellular staining specificity. Both staining methods had >90% repeatability in biological replicates. Nonspecific LacZ staining occurs in some tissues due to the presence of bacteria or endogenous enzyme activity. However, this can be effectively distinguished from reporter gene activity by the combination of the WM and FS methods. After careful annotation, LacZ staining patterns in a high percentage of mutants revealed a unique structure-function not previously reported for many of these genes. The validation of methods for LacZ staining, annotation, and expression analysis reported here provides unique insights into the function of genes for which little is currently known.


Assuntos
Regulação da Expressão Gênica/genética , Genes Reporter/genética , Óperon Lac/genética , Regiões Promotoras Genéticas/genética , Animais , Atlas como Assunto , Feminino , Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Coloração e Rotulagem , Relação Estrutura-Atividade
17.
Cell ; 159(4): 800-13, 2014 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-25417157

RESUMO

We sequenced the MSY (male-specific region of the Y chromosome) of the C57BL/6J strain of the laboratory mouse Mus musculus. In contrast to theories that Y chromosomes are heterochromatic and gene poor, the mouse MSY is 99.9% euchromatic and contains about 700 protein-coding genes. Only 2% of the MSY derives from the ancestral autosomes that gave rise to the mammalian sex chromosomes. Instead, all but 45 of the MSY's genes belong to three acquired, massively amplified gene families that have no homologs on primate MSYs but do have acquired, amplified homologs on the mouse X chromosome. The complete mouse MSY sequence brings to light dramatic forces in sex chromosome evolution: lineage-specific convergent acquisition and amplification of X-Y gene families, possibly fueled by antagonism between acquired X-Y homologs. The mouse MSY sequence presents opportunities for experimental studies of a sex-specific chromosome in its entirety, in a genetically tractable model organism.


Assuntos
Evolução Biológica , Cromossomos de Mamíferos , Camundongos Endogâmicos C57BL/genética , Análise de Sequência de DNA , Cromossomo Y , Animais , Centrômero , Cromossomos Artificiais Bacterianos/genética , Feminino , Humanos , Masculino , Filogenia , Primatas/genética , Cromossomo X
18.
J Clin Invest ; 124(12): 5368-84, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25347472

RESUMO

Growing evidence supports a link between inflammation and cancer; however, mediators of the transition between inflammation and carcinogenesis remain incompletely understood. Sphingosine-1-phosphate (S1P) lyase (SPL) irreversibly degrades the bioactive sphingolipid S1P and is highly expressed in enterocytes but downregulated in colon cancer. Here, we investigated the role of SPL in colitis-associated cancer (CAC). We generated mice with intestinal epithelium-specific Sgpl1 deletion and chemically induced colitis and tumor formation in these animals. Compared with control animals, mice lacking intestinal SPL exhibited greater disease activity, colon shortening, cytokine levels, S1P accumulation, tumors, STAT3 activation, STAT3-activated microRNAs (miRNAs), and suppression of miR-targeted anti-oncogene products. This phenotype was attenuated by STAT3 inhibition. In fibroblasts, silencing SPL promoted tumorigenic transformation through a pathway involving extracellular transport of S1P through S1P transporter spinster homolog 2 (SPNS2), S1P receptor activation, JAK2/STAT3-dependent miR-181b-1 induction, and silencing of miR-181b-1 target cylindromatosis (CYLD). Colon biopsies from patients with inflammatory bowel disease revealed enhanced S1P and STAT3 signaling. In mice with chemical-induced CAC, oral administration of plant-type sphingolipids called sphingadienes increased colonic SPL levels and reduced S1P levels, STAT3 signaling, cytokine levels, and tumorigenesis, indicating that SPL prevents transformation and carcinogenesis. Together, our results suggest that dietary sphingolipids can augment or prevent colon cancer, depending upon whether they are metabolized to S1P or promote S1P metabolism through the actions of SPL.


Assuntos
Aldeído Liases/biossíntese , Transformação Celular Neoplásica/metabolismo , Neoplasias do Colo/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentais/metabolismo , RNA Neoplásico/metabolismo , Fator de Transcrição STAT3/metabolismo , Aldeído Liases/genética , Animais , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Biópsia , Transformação Celular Neoplásica/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Regulação para Baixo/genética , Deleção de Genes , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Lisofosfolipídeos/genética , Lisofosfolipídeos/metabolismo , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , Proteínas de Neoplasias/genética , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , RNA Neoplásico/genética , Fator de Transcrição STAT3/genética , Transdução de Sinais/genética , Esfingosina/análogos & derivados , Esfingosina/genética , Esfingosina/metabolismo
19.
Nature ; 513(7517): 195-201, 2014 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-25209798

RESUMO

Gibbons are small arboreal apes that display an accelerated rate of evolutionary chromosomal rearrangement and occupy a key node in the primate phylogeny between Old World monkeys and great apes. Here we present the assembly and analysis of a northern white-cheeked gibbon (Nomascus leucogenys) genome. We describe the propensity for a gibbon-specific retrotransposon (LAVA) to insert into chromosome segregation genes and alter transcription by providing a premature termination site, suggesting a possible molecular mechanism for the genome plasticity of the gibbon lineage. We further show that the gibbon genera (Nomascus, Hylobates, Hoolock and Symphalangus) experienced a near-instantaneous radiation ∼5 million years ago, coincident with major geographical changes in southeast Asia that caused cycles of habitat compression and expansion. Finally, we identify signatures of positive selection in genes important for forelimb development (TBX5) and connective tissues (COL1A1) that may have been involved in the adaptation of gibbons to their arboreal habitat.


Assuntos
Genoma/genética , Hylobates/classificação , Hylobates/genética , Cariótipo , Filogenia , Animais , Evolução Molecular , Hominidae/classificação , Hominidae/genética , Humanos , Dados de Sequência Molecular , Retroelementos/genética , Seleção Genética , Terminação da Transcrição Genética
20.
BMC Genomics ; 15: 439, 2014 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-24906298

RESUMO

BACKGROUND: Sampling genomes with Fosmid vectors and sequencing of pooled Fosmid libraries on the Illumina platform for massive parallel sequencing is a novel and promising approach to optimizing the trade-off between sequencing costs and assembly quality. RESULTS: In order to sequence the genome of Norway spruce, which is of great size and complexity, we developed and applied a new technology based on the massive production, sequencing, and assembly of Fosmid pools (FP). The spruce chromosomes were sampled with ~40,000 bp Fosmid inserts to obtain around two-fold genome coverage, in parallel with traditional whole genome shotgun sequencing (WGS) of haploid and diploid genomes. Compared to the WGS results, the contiguity and quality of the FP assemblies were high, and they allowed us to fill WGS gaps resulting from repeats, low coverage, and allelic differences. The FP contig sets were further merged with WGS data using a novel software package GAM-NGS. CONCLUSIONS: By exploiting FP technology, the first published assembly of a conifer genome was sequenced entirely with massively parallel sequencing. Here we provide a comprehensive report on the different features of the approach and the optimization of the process.We have made public the input data (FASTQ format) for the set of pools used in this study:ftp://congenie.org/congenie/Nystedt_2013/Assembly/ProcessedData/FosmidPools/.(alternatively accessible via http://congenie.org/downloads).The software used for running the assembly process is available at http://research.scilifelab.se/andrej_alexeyenko/downloads/fpools/.


Assuntos
Vetores Genéticos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Picea/genética , Clonagem Molecular , Genoma de Planta , Sequenciamento de Nucleotídeos em Larga Escala/economia , Software
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