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1.
J Orthop Surg (Hong Kong) ; 32(1): 10225536241244825, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38607239

RESUMO

PURPOSE: This study aims to systematically review the efficacy and safety of total ankle replacement (TAR) and ankle fusion (AF) as treatment options for end-stage ankle arthritis. METHODS: A comprehensive literature search was conducted on data from multiple databases, including PubMed, The Cochrane Library, Construction and Building Materials, Embase, Web of Science, and Scopus for RCTs and prospective cohort studies comparing TAR and AF in patients with end-stage ankle arthritis from inception up to June, 2023. Our primary outcomes of interest included patients' clinical function scores and complications. We employed Review Manager 5.4 and Stata/MP 14.0 software for the meta-analysis. RESULTS: Our analysis incorporated 13 comparative studies, including 11 prospective studies, one pilot RCT, and one RCT. The pooled results revealed no significant difference in postoperative Short Form-36 scores between the TAR and AF groups (MD = -1.19, 95% CI: -3.89 to 1.50, p = .39). However, the postoperative Foot and Ankle Ability Measure scores in the AF group were significantly higher than in the TAR group (MD = 8.30, 95% CI: 1.01-15.60, p = .03). There was no significant difference in postoperative complication rates between the TAR and AF groups (RR = 0.95, 95% CI: 0.59 to 1.54, p = .85). CONCLUSION: Currently available evidence suggests no significant disparity in postoperative outcomes between TAR and AF. In the short term, TAR demonstrates better clinical scores than AF and lower complication rates. Conversely, in the long term, AF exhibits superior clinical scores and lower complication rates, although this difference is not statistically significant.


Assuntos
Artrite , Artroplastia de Substituição do Tornozelo , Humanos , Tornozelo , Estudos Prospectivos , Articulação do Tornozelo/cirurgia , Artrite/cirurgia
2.
Blood ; 142(4): 382-396, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37267508

RESUMO

Sickle cell disease (SCD) is a chronic hemolytic and systemic hypoxia condition with constant oxidative stress and significant metabolic alterations. However, little is known about the correlation between metabolic alterations and the pathophysiological symptoms. Here, we report that Nrf2, a master regulator of cellular antioxidant responses, regulates the production of the metabolite l-2-hydroxyglutarate (L2HG) to mediate epigenetic histone hypermethylation for gene expression involved in metabolic, oxidative, and ferroptotic stress responses in SCD. Mechanistically, Nrf2 was found to regulate the expression of L2HG dehydrogenase (L2hgdh) to mediate L2HG production under hypoxia. Gene expression profile analysis indicated that reactive oxygen species (ROS) and ferroptosis responses were the most significantly affected signaling pathways after Nrf2 ablation in SCD. Nrf2 silencing and L2HG supplementation sensitize human sickle erythroid cells to ROS and ferroptosis stress. The absence of Nrf2 and accumulation of L2HG significantly affect histone methylation for chromatin structure modification and reduce the assembly of transcription complexes on downstream target genes to regulate ROS and ferroptosis responses. Furthermore, pharmacological activation of Nrf2 was found to have protective effects against ROS and ferroptosis stress in SCD mice. Our data suggest a novel mechanism by which Nrf2 regulates L2HG levels to mediate SCD severity through ROS and ferroptosis stress responses, suggesting that targeting Nrf2 is a viable therapeutic strategy for ameliorating SCD symptoms.


Assuntos
Anemia Falciforme , Cromatina , Epigênese Genética , Ferroptose , Glutaratos , Fator 2 Relacionado a NF-E2 , Ferroptose/genética , Glutaratos/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Anemia Falciforme/genética , Anemia Falciforme/metabolismo , Anemia Falciforme/patologia , Cromatina/metabolismo , Metilação , Oxirredutases do Álcool/metabolismo , Animais , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Transcrição Gênica , Perfilação da Expressão Gênica
3.
Mol Cancer Res ; 21(10): 1079-1092, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37364049

RESUMO

Correlations between the oxidative stress response and metabolic reprogramming have been observed during malignant tumor formation; however, the detailed mechanism remains elusive. The transcription factor Nrf2, a master regulator of the oxidative stress response, mediates metabolic reprogramming in multiple cancers. In a mouse model of hepatocellular carcinoma (HCC), through metabolic profiling, genome-wide gene expression, and chromatin structure analyses, we present new evidence showing that in addition to altering antioxidative stress response signaling, Nrf2 ablation impairs multiple metabolic pathways to reduce the generation of acetyl-CoA and suppress histone acetylation in tumors, but not in tumor-adjacent normal tissue. Nrf2 ablation and dysregulated histone acetylation impair transcription complex assembly on downstream target antioxidant and metabolic regulatory genes for expression regulation. Mechanistic studies indicate that the regulatory function of Nrf2 is low glucose dependent, the effect of which is demolished under energy refeeding. Together, our results implicate an unexpected effect of Nrf2 on acetyl-CoA generation, in addition to its classic antioxidative stress response regulatory activity, integrates metabolic and epigenetic programs to drive HCC progression. IMPLICATIONS: This study highlights that Nrf2 integrates metabolic and epigenetic regulatory networks to dictate tumor progression and that Nrf2 targeting is therapeutically exploitable in HCC treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Acetilcoenzima A/genética , Acetilcoenzima A/metabolismo , Carcinoma Hepatocelular/patologia , Epigênese Genética , Histonas/metabolismo , Neoplasias Hepáticas/patologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-34476412

RESUMO

Tumor angiogenesis is a hallmark of cancer. Therapeutic drug inhibitors targeting angiogenesis are clinically effective. We have previously identified GT198 (gene symbol PSMC3IP, also known as Hop2) as an oncoprotein that induces tumor angiogenesis in human cancers, including oral cancer. In this study, we show that the GT198 protein is a direct drug target of more than a dozen oncology drugs and several clinically successful anticancer herbs. GT198 is a DNA repair protein that binds to DNA. Using an in vitro DNA-binding assay, we tested the approved oncology drug set VII from the National Cancer Institute containing 129 oncology drugs. Identified GT198 inhibitors include but are not limited to mitoxantrone, doxorubicin, paclitaxel, etoposide, dactinomycin, and imatinib. Paclitaxel and etoposide have higher binding affinities, whereas doxorubicin has higher binding efficacy due to competitive inhibition. GT198 shares protein sequence homology with DNA topoisomerases, which are known drug targets, so that GT198 is likely a new drug target previously unrecognized. To seek more powerful GT198 inhibitors, we further tested several anticancer herbal extracts. The positive anticancer herbs with high affinity and high efficacy are all clinically successful ones, including allspice from Jamaica, Gleditsia sinensis or honey locust from China, and BIRM from Ecuador. Partial purification of allspice using an organic chemical approach demonstrated great feasibility of natural product purification, when the activity is monitored by the in vitro DNA-binding assay using GT198 as a target. Together, our study reveals GT198 as a new targeting mechanism for existing oncology drugs. The study also delivers an excellent drug target suitable for compound identification and natural product purification. In particular, this study opens an opportunity to rapidly identify drugs with high efficacy and low toxicity from nature.

5.
Mol Cancer Res ; 18(3): 463-476, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31744878

RESUMO

Deregulated oncogenic signaling linked to PI3K/AKT and mTORC1 pathway activation is a hallmark of human T-cell acute leukemia (T-ALL) pathogenesis and contributes to leukemic cell resistance and adverse prognosis. Notably, although the multiagent chemotherapy of leukemia leads to a high rate of complete remission, options for salvage therapy for relapsed/refractory disease are limited due to the serious side effects of augmenting cytotoxic chemotherapy. We report that ablation of HSF1, a key transcriptional regulator of the chaperone response and cellular bioenergetics, from mouse T-ALL tumors driven by PTEN loss or human T-ALL cell lines, has significant therapeutic effects in reducing tumor burden and sensitizing malignant cell death. From a mechanistic perspective, the enhanced sensitivity of T-ALLs to HSF1 depletion resides in the reduced MAPK-ERK signaling and metabolic and ATP-producing capacity of malignant cells lacking HSF1 activity. Impaired mitochondrial ATP production and decreased intracellular amino acid content in HSF1-deficient T-ALL cells trigger an energy-saving adaptive response featured by attenuation of the mTORC1 activity, which is coregulated by ATP, and its downstream target proteins (p70S6K and 4E-BP). This leads to protein translation attenuation that diminishes oncogenic signals and malignant cell growth. Collectively, these metabolic alterations in the absence of HSF1 activity reveal cancer cell liabilities and have a profound negative impact on T-ALL progression. IMPLICATIONS: Targeting HSF1 and HSF1-dependent cancer-specific anabolic and protein homeostasis programs has a significant therapeutic potential for T-ALL and may prevent progression of relapsed/refractory disease.


Assuntos
Fatores de Transcrição de Choque Térmico/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Animais , Linhagem Celular Tumoral , Progressão da Doença , Metabolismo Energético , Feminino , Humanos , Masculino , Camundongos , Transdução de Sinais
6.
Mol Cell Biol ; 39(9)2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30745413

RESUMO

Delineating the mechanisms that drive hepatic injury and hepatocellular carcinoma (HCC) progression is critical for development of novel treatments for recurrent and advanced HCC but also for the development of diagnostic and preventive strategies. Heat shock protein 70 (HSP70) acts in concert with several cochaperones and nucleotide exchange factors and plays an essential role in protein quality control that increases survival by protecting cells against environmental stressors. Specifically, the HSP70-mediated response has been implicated in the pathogenesis of cancer, but the specific mechanisms by which HSP70 may support malignant cell transformation remains to be fully elucidated. Here, we show that genetic ablation of HSP70 markedly impairs HCC initiation and progression by distinct but overlapping pathways. This includes the potentiation of the carcinogen-induced DNA damage response, at the tumor initiation stage, to increase the p53-dependent surveillance response leading to the cell cycle exit or death of genomically damaged differentiated pericentral hepatocytes, and this may also prevent their conversion into more proliferating HCC progenitor cells. Subsequently, activation of a mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) negative feedback pathway diminishes oncogenic signals, thereby attenuating premalignant cell transformation and tumor progression. Modulation of HSP70 function may be a strategy for interfering with oncogenic signals driving liver cell transformation and tumor progression, thus providing an opportunity for human cancer control.


Assuntos
Carcinoma Hepatocelular/patologia , Transformação Celular Neoplásica/genética , Dietilnitrosamina/efeitos adversos , Proteínas de Choque Térmico HSP70/genética , Neoplasias Hepáticas/patologia , Animais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Dano ao DNA , Progressão da Doença , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Proteína Supressora de Tumor p53/metabolismo
7.
J Cell Biol ; 216(3): 723-741, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28183717

RESUMO

Metabolic energy reprogramming facilitates adaptations to a variety of stress conditions and cellular dysfunction, but how the energetic demands are monitored and met in response to physiological stimuli remains elusive. Our data support a model demonstrating that heat shock factor 1 (HSF1), a master transcriptional regulator of the chaperone response, has been coopted from its role as a critical protein quality-control regulator to having a central role in systemic energy sensing and for metabolic adaptation to nutrient availability. We found that in the absence of HSF1, levels of NAD+ and ATP are not efficiently sustained in hepatic cells, largely because of transcriptional repression of nicotinamide phosphoribosyltransferase in the NAD+ salvage pathway. Mechanistically, the defect in NAD+ and ATP synthesis linked to a loss of NAD+-dependent deacetylase activity, increased protein acetylation, and impaired mitochondrial integrity. Remarkably, the drop in ATP level caused by HSF1 loss invoked an adaptive response featuring the inhibition of energetically demanding processes, including gluconeogenesis, translation, and lipid synthesis. Our work identifies HSF1 as a central regulator of cellular bioenergetics and protein homeostasis that benefits malignant cell progression and exacerbates development of metabolic diseases.


Assuntos
Proteínas de Ligação a DNA/genética , Metabolismo Energético/genética , Homeostase/genética , Fígado/fisiologia , Chaperonas Moleculares/genética , Fatores de Transcrição/genética , Transcrição Gênica/genética , Trifosfato de Adenosina/metabolismo , Animais , Regulação da Expressão Gênica/genética , Fatores de Transcrição de Choque Térmico , Proteínas de Choque Térmico/genética , Resposta ao Choque Térmico/genética , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NAD/metabolismo , Processamento de Proteína Pós-Traducional/genética
8.
J Neurochem ; 130(5): 626-41, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24903326

RESUMO

Traumatic brain injury (TBI) induces severe harm and disability in many accident victims and combat-related activities. The heat-shock proteins Hsp70/Hsp110 protect cells against death and ischemic damage. In this study, we used mice deficient in Hsp110 or Hsp70 to examine their potential requirement following TBI. Data indicate that loss of Hsp110 or Hsp70 increases brain injury and death of neurons. One of the mechanisms underlying the increased cell death observed in the absence of Hsp110 and Hsp70 following TBI is the increased expression of reactive oxygen species-induced p53 target genes Pig1, Pig8, and Pig12. To examine whether drugs that increase the levels of Hsp70/Hsp110 can protect cells against TBI, we subjected mice to TBI and administered Celastrol or BGP-15. In contrast to Hsp110- or Hsp70i-deficient mice that were not protected following TBI and Celastrol treatment, there was a significant improvement of wild-type mice following administration of these drugs during the first week following TBI. In addition, assessment of neurological injury shows significant improvement in contextual and cued fear conditioning tests and beam balance in wild-type mice that were treated with Celastrol or BGP-15 following TBI compared to TBI-treated mice. These studies indicate a significant role of Hsp70/Hsp110 in neuronal survival following TBI and the beneficial effects of Hsp70/Hsp110 inducers toward reducing the pathological consequences of TBI. Our data indicate that loss of Hsp110 or Hsp70 in mice increases brain injury following TBI. (a) One of the mechanisms underlying the increased cell death observed in the absence of these Hsps following TBI is the increased expression of ROS-induced p53 target genes known as Pigs. In addition, (b) using drugs (Celastrol or BGP-15) to increase Hsp70/Hsp110 levels protect cells against TBI, suggesting the beneficial effects of Hsp70/Hsp110 inducers to reduce the pathological consequences of TBI.


Assuntos
Lesões Encefálicas/metabolismo , Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Choque Térmico HSP72/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Immunoblotting , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase Multiplex , Análise de Sequência com Séries de Oligonucleotídeos , Oximas/farmacologia , Triterpenos Pentacíclicos , Piperidinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Triterpenos/farmacologia
9.
J Forensic Sci ; 59(4): 898-908, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24814664

RESUMO

The discriminatory power of the noncoding control region (CR) of domestic dog mitochondrial DNA alone is relatively low. The extent to which the discriminatory power could be increased by analyzing additional highly variable coding regions of the mitochondrial genome (mtGenome) was therefore investigated. Genetic variability across the mtGenome was evaluated by phylogenetic analysis, and the three most variable ~1 kb coding regions identified. We then sampled 100 Swedish dogs to represent breeds in accordance with their frequency in the Swedish population. A previously published dataset of 59 dog mtGenomes collected in the United States was also analyzed. Inclusion of the three coding regions increased the exclusion capacity considerably for the Swedish sample, from 0.920 for the CR alone to 0.964 for all four regions. The number of mtDNA types among all 159 dogs increased from 41 to 72, the four most frequent CR haplotypes being resolved into 22 different haplotypes.


Assuntos
DNA Mitocondrial/genética , Cães/genética , Análise de Sequência de DNA , Animais , Bases de Dados de Ácidos Nucleicos , Genoma , Haplótipos , Região de Controle de Locus Gênico , Reação em Cadeia da Polimerase
10.
Hepatology ; 59(4): 1448-58, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24122861

RESUMO

UNLABELLED: Immunization with effective cancer vaccines can offer a much needed adjuvant therapy to fill the treatment gap after liver resection to prevent relapse of hepatocellular carcinoma (HCC). However, current HCC cancer vaccines are mostly based on native shared-self/tumor antigens that are only able to induce weak immune responses. In this study we investigated whether the HCC-associated self/tumor antigen of alpha-fetoprotein (AFP) could be engineered to create an effective vaccine to break immune tolerance and potently activate CD8 T cells to prevent clinically relevant carcinogen-induced autochthonous HCC in mice. We found that the approach of computer-guided methodical epitope-optimization created a highly immunogenic AFP and that immunization with lentivector expressing the epitope-optimized AFP, but not wild-type AFP, potently activated CD8 T cells. Critically, the activated CD8 T cells not only cross-recognized short synthetic wild-type AFP peptides, but also recognized and killed tumor cells expressing wild-type AFP protein. Immunization with lentivector expressing optimized AFP, but not native AFP, completely protected mice from tumor challenge and reduced the incidence of carcinogen-induced autochthonous HCC. In addition, prime-boost immunization with the optimized AFP significantly increased the frequency of AFP-specific memory CD8 T cells in the liver that were highly effective against emerging HCC tumor cells, further enhancing the tumor prevention of carcinogen-induced autochthonous HCC. CONCLUSIONS: Epitope-optimization is required to break immune tolerance and potently activate AFP-specific CD8 T cells, generating effective antitumor effect to prevent clinically relevant carcinogen-induced autochthonous HCC in mice. Our study provides a practical roadmap to develop effective human HCC vaccines that may result in an improved outcome compared to the current HCC vaccines based on wild-type AFP.


Assuntos
Vacinas Anticâncer/uso terapêutico , Carcinoma Hepatocelular/prevenção & controle , Epitopos , Neoplasias Hepáticas/prevenção & controle , alfa-Fetoproteínas/genética , Animais , Linfócitos T CD8-Positivos/patologia , Carcinógenos , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/imunologia , Modelos Animais de Doenças , Tolerância Imunológica/fisiologia , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Resultado do Tratamento
11.
Am J Transl Res ; 5(4): 427-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23724166

RESUMO

As a versatile regulatory mechanism, sumoylation has been found to be essential for ordered diverse cellular processes. However, the exact impact of sumoylation on endothelial function largely remained elusive. Here we investigated the role of small ubiquitin-like modifier 1 (SUMO1) mediated sumoylation in the regulation of endothelial function by examining its effect on angiogenesis and homeostatic responses. Adenoviral-mediated SUMO1 expression in porcine aortic endothelial cells (PAECs) dose-dependently promoted proliferation, migration and tube formation. In line with these results in PAECs, Matrigel plug assays in SUMO1 transgenic mice demonstrated a significant higher capacity for vascular neogenesis as compared with that of control littermates. Moreover, SUMO1 expression protected PAECs from serum starvation or H2O2-induced apoptosis. Mechanistic studies demonstrated that SUMO1 sumoylation modulates ERK1/2 activation and MMP13 expression as well as Jak2/STAT5 signaling to promote angiogenesis. SUMO1 sumoylation also suppressed NFκB and c-JUN transcriptional activity to provide protection for PAECs against oxidative stress-induced apoptosis. Given that sumoylation is a reversible process, dynamic regulation of the sumoylation function could be a novel strategy to modulate endothelial function in disease states.

12.
Am J Pathol ; 183(2): 617-25, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23747947

RESUMO

A number of inhibitors have been used to dissect the functional relevance of Jak2 in endothelial homeostasis, with disparate results. Given that Jak2 deficiency leads to embryonic lethality, the exact role of Jak2 in the regulation of postnatal endothelial function is yet to be fully elucidated. We generated a model in which Jak2 deficiency can be induced by tamoxifen in adult mice. Loss of Jak2 significantly impaired endothelium-dependent response capacity for vasodilators. Matrigel plug assays indicated a notable decrease in endothelial angiogenic function in Jak2-deficient mice. Studies in a hindlimb ischemic model indicated that Jak2 activity is likely to be a prerequisite for prompt perfusion recovery, based on the concordance of temporal changes in Jak2 expression during the course of ischemic injury and perfusion recovery. A remarkable delay in perfusion recovery, along with reduced capillary and arteriole formation, was observed in Jak2-deficient mice. Antibody array studies indicated that loss of Jak2 led to repressed eNOS expression. In mechanistic studies, Jak2 deficiency attenuated Raf-1/MEK1 signaling, which then reduced activity of Sp-1, an essential transcription factor responsible for eNOS expression. These data are important not only for understanding the exact role that Jak2 plays in endothelial homeostasis, but also for assessing Jak2-based therapeutic strategies in a variety of clinical settings.


Assuntos
Janus Quinase 2/deficiência , MAP Quinase Quinase 1/fisiologia , Óxido Nítrico Sintase Tipo III/metabolismo , Proteínas Quinases/fisiologia , Proteínas Proto-Oncogênicas c-raf/fisiologia , Animais , Aorta/efeitos dos fármacos , Aorta/enzimologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/enzimologia , Endotélio Vascular/fisiologia , Inibidores Enzimáticos/farmacologia , Membro Posterior/irrigação sanguínea , Isquemia/enzimologia , Janus Quinase 2/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Tamoxifeno/farmacologia , Vasodilatadores/farmacologia
13.
Funct Integr Genomics ; 13(2): 229-39, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23455933

RESUMO

Nicotianamine (NA) is an important divalent metal chelator and the main precursor of phytosiderophores. NA is synthesized from S-adenosylmethionine in a process catalyzed by nicotianamine synthase (NAS). In this study, a set of structural and phylogenetic analyses have been applied to identify the maize NAS genes based on the maize genome sequence release. Ten maize NAS genes have been mapped; seven of them have not been reported to date. Phylogenetic analysis and expression pattern from microarray data led to their classification into two different orthologous groups. C-terminal fusion of ZmNAS3 with GFP was found in the cytoplasm of Arabidopsis leaf protoplast. Expression analysis by reverse transcription polymerase chain reaction revealed ZmNAS genes are responsive to heavy metal ions (Ni, Fe, Cu, Mn, Zn, and Cd), and all 10 ZmNAS genes were only observed in the root tissue except of ZmNAS6. The promoter of ZmNAS genes was analyzed for the presence of different cis-element response to all kinds of phytohormones and environment stresses. We found that the ZmNAS gene expression of maize seedlings was regulated by jasmonic acid, abscisic acid, and salicylic acid. Microarray data demonstrated that the ZmNAS genes show differential, organ-specific expression patterns in the maize developmental steps. The integrated comparative analysis can improve our current view of ZmNAS genes and facilitate the functional characterization of individual members.


Assuntos
Alquil e Aril Transferases/genética , Genes de Plantas/genética , Metais Pesados/toxicidade , Família Multigênica , Reguladores de Crescimento de Plantas/farmacologia , Zea mays/enzimologia , Zea mays/genética , Biocatálise/efeitos dos fármacos , Citoplasma/efeitos dos fármacos , Citoplasma/enzimologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Modelos Moleculares , Análise de Sequência com Séries de Oligonucleotídeos , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Filogenia , Regiões Promotoras Genéticas/genética , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/genética , S-Adenosilmetionina/química , S-Adenosilmetionina/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Homologia Estrutural de Proteína , Zea mays/efeitos dos fármacos
14.
Funct Integr Genomics ; 12(4): 683-91, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22983498

RESUMO

Maize (Zea mays ssp. mays L.) is an important model organism for fundamental research in the agro-biotechnology field. Aldehydes were generated in response to a suite of environmental stresses that perturb metabolism including salinity, dehydration, desiccation, and cold and heat shock. Many biologically important aldehydes are metabolized by the superfamily of NAD(P)(+)-dependent aldehyde dehydrogenases. Here, starting from the database of Z. mays, we identified 28 aldehyde dehydrogenase (ALDH) genes and 48 transcripts by the in silico cloning method using the ALDH-conserved domain amino acid sequence of Arabidopsis and rice as a probe. Phylogenetic analysis shows that all 28 members of the ALDH gene families were classified to ten distinct subfamilies. Microarray data and quantitative real-time PCR analysis reveal that ZmALDH9, ZmALDH13, and ZmALDH17 genes involve the function of drought stress, acid tolerance, and pathogens infection. These results suggested that these three ZmALDH genes might be potentially useful in maize genetic improvement.


Assuntos
Aldeído Desidrogenase/genética , Família Multigênica , Zea mays/genética , Aldeído Desidrogenase/química , Bases de Dados de Ácidos Nucleicos , Regulação da Expressão Gênica de Plantas , Filogenia , Estrutura Terciária de Proteína , RNA Mensageiro/biossíntese , Análise de Sequência de DNA , Estresse Fisiológico , Zea mays/enzimologia
15.
Am J Pathol ; 181(3): 937-46, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22796409

RESUMO

microRNAs (miRNAs) have regulated the expression and function of genes implicated in many pathological settings, but their impact on the pathoetiological characteristics of overactive bladder (OAB) largely remains unknown. We have generated a mouse model in which adult mice can be induced for detrusor deletion of Dicer, an enzyme essential for miRNA processing. Targeted deletion of Dicer did not lead to a significant change for detrusor functionality under physiological conditions; however, loss of Dicer exacerbated cyclophosphamide-induced OAB, manifested by the higher severity of altered detrusor contractile force and sensitivity, abnormal urodynamics, and enhanced macrophage infiltration. Mechanistic studies revealed that loss of Dicer may impair the expression of miRNAs that are capable of targeting P2x mRNAs. As a result, mice deficient in Dicer manifest enhanced P2X expression in the detrusor on cyclophosphamide treatment, predisposing to the increased risk for OAB development. More important, studies using bladder biopsy samples of patients with OAB also demonstrated similar results as those found in animals. Taken together, our results suggest that miRNAs modulate OAB susceptibility by regulating purinergic signaling, in which the pathogenic insult induces the expression of miRNAs capable of targeting P2X mRNAs to suppress OAB symptoms.


Assuntos
RNA Helicases DEAD-box/deficiência , RNA Helicases DEAD-box/metabolismo , Receptores Purinérgicos/metabolismo , Ribonuclease III/deficiência , Ribonuclease III/metabolismo , Transdução de Sinais , Bexiga Urinária Hiperativa/metabolismo , Animais , Sequência de Bases , Western Blotting , Biologia Computacional , Ciclofosfamida , Deleção de Genes , Regulação da Expressão Gênica , Marcação de Genes , Humanos , Imuno-Histoquímica , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Dados de Sequência Molecular , Contração Muscular/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Bexiga Urinária/patologia , Bexiga Urinária/fisiopatologia , Bexiga Urinária Hiperativa/induzido quimicamente , Bexiga Urinária Hiperativa/patologia , Bexiga Urinária Hiperativa/fisiopatologia
16.
Mycologia ; 102(6): 1318-38, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20943565

RESUMO

Colletotrichum interacts with numerous plant species overtly as symptomatic pathogens and cryptically as asymptomatic endophytes. It is not known whether these contrasting ecological modes are optional strategies expressed by individual Colletotrichum species or whether a species' ecology is explicitly pathogenic or endophytic. We explored this question by inferring relationships among 77 C. gloeosporioides s.l. strains isolated from asymptomatic leaves and from anthracnose lesions on leaves and fruits of Theobroma cacao (cacao) and other plants from Panamá. ITS and 5'-tef1 were used to assess diversity and to delineate operational taxonomic units for multilocus phylogenetic analysis. The ITS and 5'-tef1 screens concordantly resolved four strongly supported lineages, clades A-D: Clade A includes the ex type of C. gloeosporioides, clade B includes the ex type ITS sequence of C. boninense, and clades C and D are unidentified. The ITS yielded limited resolution and support within all clades, in particular the C. gloeosporioides clade (A), the focal lineage dealt with in this study. In contrast the 5'-tef1 screen differentiated nine distinctive haplotype subgroups within the C. gloeosporioides clade that were concordant with phylogenetic terminals resolved in a five-locus nuclear phylogeny. Among these were two phylogenetic species associated with symptomatic infections specific to either cacao or mango and five phylogenetic species isolated principally as asymptomatic infections from cacao and other plant hosts. We formally describe two new species, C. tropicale and C. ignotum, that are frequent asymptomatic associates of cacao and other Neotropical plant species, and epitypify C. theobromicola, which is associated with foliar and fruit anthracnose lesions of cacao. Asymptomatic Colletotrichum strains isolated from cacao plants grown in China included six distinct C. gloeosporioides clade taxa, only one of which is known to occur in the Neotropics.


Assuntos
Cacau/microbiologia , Colletotrichum/classificação , Colletotrichum/isolamento & purificação , Interações Hospedeiro-Patógeno , Filogenia , Simbiose , Cacau/fisiologia , Colletotrichum/genética , Colletotrichum/fisiologia , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , Panamá
17.
Mol Ecol ; 19(16): 3406-20, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20666999

RESUMO

Historical drainage patterns adjacent to the Qinghai-Tibetan Plateau differed markedly from those of today. We examined the relationship between drainage history and geographic patterns of genetic variation in the Yunnan spiny frog, Nanorana yunnanensis, using approximately 981 base pairs of mitochondrial DNA partial sequences from protein-coding genes ND1 and ND2, and intervening areas including complete tRNA(Ile), tRNA(Gln) and tRNA(Met). Two null hypotheses were tested: (i) that genetic patterns do not correspond to the development of drainage systems and (ii) that populations had been stable and not experienced population expansion, bottlenecking and selection. Genealogical analyses identified three, major, well-supported maternal lineages, each of which had two sublineages. These divergent lineages were completely concordant with six geographical regions. Genetic structure and divergence were strongly congruent with historical rather than contemporary drainage patterns. Most lineages and sublineages were formed via population fragmentation during the rearrangement of paleodrainage basins in the Early Pliocene and Early Pleistocene. Sympatric lineages occurred only in localities at the boundaries of major drainages, likely reflecting secondary contact of previously allopatric populations. Extensive population expansion probably occurred early in the Middle Pleistocene accompanying dramatic climatic oscillations.


Assuntos
Ecossistema , Evolução Molecular , Genética Populacional , Filogenia , Ranidae/genética , Animais , Teorema de Bayes , China , DNA Mitocondrial/genética , Geografia , Haplótipos , NADH Desidrogenase/genética , RNA de Transferência de Glutamina/genética , RNA de Transferência de Isoleucina/genética , RNA de Transferência de Metionina/genética , Alinhamento de Sequência , Análise de Sequência de DNA
18.
Am J Hum Genet ; 86(6): 957-62, 2010 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-20560209

RESUMO

Previously, we localized the defective gene for the urofacial syndrome (UFS) to a region on chromosome 10q24 by homozygosity mapping. We now report evidence that Heparanse 2 (HPSE2) is the culprit gene for the syndrome. Mutations with a loss of function in the Heparanase 2 (HPSE2) gene were identified in all UFS patients originating from Colombia, the United States, and France. HPSE2 encodes a 592 aa protein that contains a domain showing sequence homology to the glycosyl hydrolase motif in the heparanase (HPSE) gene, but its exact biological function has not yet been characterized. Complete loss of HPSE2 function in UFS patients suggests that HPSE2 may be important for the synergic action of muscles implicated in facial expression and urine voiding.


Assuntos
Facies , Genes Recessivos , Glucuronidase/genética , Doenças Urológicas/genética , Mapeamento Cromossômico , Feminino , Humanos , Masculino , Mutação , Linhagem , Síndrome
19.
Mol Biol Evol ; 26(12): 2849-64, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19723671

RESUMO

There is no generally accepted picture of where, when, and how the domestic dog originated. Previous studies of mitochondrial DNA (mtDNA) have failed to establish the time and precise place of origin because of lack of phylogenetic resolution in the so far studied control region (CR), and inadequate sampling. We therefore analyzed entire mitochondrial genomes for 169 dogs to obtain maximal phylogenetic resolution and the CR for 1,543 dogs across the Old World for a comprehensive picture of geographical diversity. Hereby, a detailed picture of the origins of the dog can for the first time be suggested. We obtained evidence that the dog has a single origin in time and space and an estimation of the time of origin, number of founders, and approximate region, which also gives potential clues about the human culture involved. The analyses showed that dogs universally share a common homogenous gene pool containing 10 major haplogroups. However, the full range of genetic diversity, all 10 haplogroups, was found only in southeastern Asia south of Yangtze River, and diversity decreased following a gradient across Eurasia, through seven haplogroups in Central China and five in North China and Southwest (SW)Asia, down to only four haplogroups in Europe. The mean sequence distance to ancestral haplotypes indicates an origin 5,400-16,300 years ago (ya) from at least 51 female wolf founders. These results indicate that the domestic dog originated in southern China less than 16,300 ya, from several hundred wolves. The place and time coincide approximately with the origin of rice agriculture, suggesting that the dogs may have originated among sedentary hunter-gatherers or early farmers, and the numerous founders indicate that wolf taming was an important culture trait.


Assuntos
DNA Mitocondrial/genética , Cães/genética , Filogenia , Rios , Lobos/genética , Animais , Sudeste Asiático , China , Europa (Continente) , Feminino , Pool Gênico , Genoma Mitocondrial/genética , Geografia , Haplótipos/genética , Região de Controle de Locus Gênico/genética , Dados de Sequência Molecular , Fatores de Tempo
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