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1.
J Dig Dis ; 24(4): 262-270, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37283197

RESUMO

OBJECTIVES: To assess the predictive value of endoscopic grading of gastric atrophy using Kimura-Takemoto classification, histological grading systems of operative link on gastritis assessment (OLGA) and operative link on gastric intestinal metaplasia (OLGIM) on risk stratification for early gastric cancer (EGC) and other potential risk factors of EGC. METHODS: A single-center, case-control study was retrospectively conducted including 68 patients with EGC treated with endoscopic submucosal dissection and 68 age- and sex-matched control subjects. Kimura-Takemoto classification, OLGA and OLGIM systems, and other potential risk factors were evaluated between the two groups. RESULTS: Of the 68 EGC lesions, 22 (32.4%) were well differentiated, 38 (55.9%) were moderately differentiated, and 8 (11.8%) were poorly differentiated, respectively. Multivariate analysis revealed O-type Kimura-Takemoto classification (adjusted odds ratio [AOR] 3.282, 95% confidence interval [CI] 1.106-9.744, P = 0.032) and OLGIM stage III/IV (AOR 17.939, 95% CI 1.874-171.722, P = 0.012) were significantly related to a higher risk of EGC. Especially, O-type Kimura-Takemoto classification within 6-12 months before EGC diagnosis (AOR 4.780, 95% CI 1.650-13.845, P = 0.004) was independently associated with EGC risk. Areas under the receiver operating characteristic curve of the three systems for EGC were comparable. CONCLUSIONS: Endoscopic Kimura-Takemoto classification and histological OLGIM stage III/IV are independent risk factors for EGC, which may reduce the need for biopsies in risk stratification of EGC. Further multicenter prospective studies of large sizes are needed.


Assuntos
Gastrite Atrófica , Gastrite , Neoplasias Gástricas , Humanos , Estudos de Casos e Controles , Neoplasias Gástricas/diagnóstico , Estudos Retrospectivos , Estudos Prospectivos , Gastrite/complicações , Gastrite/patologia , Gastrite Atrófica/diagnóstico , Medição de Risco , Fatores de Risco , Metaplasia , Atrofia
2.
BMC Neurol ; 23(1): 81, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36814261

RESUMO

BACKGROUND: Ectopic pituitary adenoma (EPA) is defined as a special type of pituitary adenoma that originates outside of the sellar region, is extra- or intra-cranially located, and without connection to normal pituitary tissue. EPA is extremely rare, with most cases presented as case reports or small case series. Due to nonspecific symptoms and laboratory indicators, the preoperative diagnosis, treatment and management for EPA remain challenging. CASE PRESENTATION: Here, we report the imaging phenotype and pathological findings of a case of invasive EPA in a 47-year-old woman. A preoperative non-contrast CT scan revealed a 5.8 × 3.6 × 3.7 cm soft tissue mass located in the sphenoid sinus and clivus. MRI showed an ill-defined solid mass with heterogeneous signals on T1-weighted and T2-weighted images. The mass displayed infiltrative growth pattern, destroying bone of the skull base, invading adjacent muscles and encasing vessels. The patient underwent partial tumor resection via transsphenoidal endoscopic surgery. Pathological examination led to diagnosis of ectopic ACTH-secreting pituitary adenoma. Post-surgery, the patient received external beam radiotherapy. CONCLUSION: EPA with invasive growth pattern has rarely been reported. The imaging phenotype displays its relationship to the pituitary tissue and surrounding structures. Immunohistochemical examination acts as a crucial role in differentiating EPA from other skull base tumors. This case report adds to the literature on EPA by summarizing its characteristics alongside a review of the literature.


Assuntos
Adenoma Hipofisário Secretor de ACT , Adenoma , Cordoma , Neoplasias Hipofisárias , Humanos , Adenoma Hipofisário Secretor de ACT/diagnóstico , Adenoma Hipofisário Secretor de ACT/patologia , Adenoma Hipofisário Secretor de ACT/cirurgia , Neoplasias Hipofisárias/cirurgia , Adenoma/cirurgia , Hipófise/cirurgia , Imageamento por Ressonância Magnética
3.
Front Cell Dev Biol ; 10: 961675, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36120581

RESUMO

Ufmylation (UFM1 modification) is a newly identified ubiquitin-like modification system involved in numerous cellular processes. However, the regulatory mechanisms and biological functions of this modification remain mostly unknown. We have recently reported that Ufmylation family genes have frequent somatic copy number alterations in human cancer including melanoma, suggesting involvement of Ufmylation in skin function and disease. UFL1 is the only known Ufmylation E3-like ligase. In this study, we generated the skin-specific Ufl1 knockout mice and show that ablation of Ufl1 caused epidermal thickening, pigmentation and shortened life span. RNA-Seq analysis indicated that Ufl1 deletion resulted in upregulation of the genes involved in melanin biosynthesis. Mechanistically, we found that Endothelin-1 (ET-1) is a novel substrate of Ufmylation and this modification regulates ET-1 stability, and thereby deletion of Ufl1 upregulates the expression and secretion of ET-1, which in turn results in up-regulation of genes in melanin biosynthesis and skin pigmentation. Our findings establish the role of Ufl1 in skin pigmentation through Ufmylation modification of ET-1 and provide opportunities for therapeutic intervention of skin diseases.

4.
J Ethnopharmacol ; 285: 114887, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34864127

RESUMO

ETHNOPHARMALOGICAL RELEVANCE: Cortex Juglandis Mandshuricae (CJM) is the dry branch or stem bark of the Juglans mandshurica Maxim. and is widely used as a traditional Chinese medicine in Asia and Africa. Its use was first recorded in Kaibao Bencao. AIM OF THE STUDY: The present review provides a deeper insight, better awareness and detailed knowledge of phytochemistry, pharmacology, quality control, along with clinical applications of Cortex Juglandis Mandshuricae. METHODS: The relevant information of Cortex Juglandis Mandshuricae was obtained from several databases including Web of Science, PubMed, and CNKI. The medical books, PhD and MSc dissertations in Chinese were also used to perform this work. RESULTS: CJM has been traditionally used against a wide range of diseases, including dysentery, acute conjunctivitis, bacterial infections, and cancer. A total of 249 compounds have been isolated from CJM; they mainly include quinones and their derivatives, flavonoids, tannins, diarylheptanoids, triterpenoids, coumarins, phenylpropanoids, and volatile oils. These compounds exert anti-tumor, anti-oxidant, anti-inflammatory, bacteriostatic, anti-complement, immunomodulatory, anti-parasitic activities. Specifically, the effects of juglone, alkaloids and unsaturated fatty acid CJM components against hepatic cancer occur through exertion of apoptosis through a mitochondria-dependent pathway. In addition, taxifolin and several tannins have been found to have anti-HIV activity, and (±)-juglanaloid A and (±)-juglanaloid B target Alzheimer disease. Quality control is monitored through identification of juglone, quercetin, and volatile oils. A clinical preparation of CJM, Compound Muji Granules, is used in the treatment of various liver diseases with good therapeutic effect. CONCLUSION: While CJM has been used extensively as a folk medicine, the relationships between structure and activity remain unclear. More in vivo models are needed to study the pharmacological mechanisms of action and to assess potential toxic components, in addition to which the evidence used to demonstrate the quality standards of medicinal materials is clearly inadequate. Therefore, more in-depth research is needed to provide a reasonable scientific basis improve its clinical utilization.


Assuntos
Medicamentos de Ervas Chinesas , Juglans , Fitoterapia , Extratos Vegetais , Animais , Humanos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Juglans/química , Compostos Fitoquímicos , Extratos Vegetais/química , Extratos Vegetais/farmacologia
5.
FEBS Lett ; 592(3): 356-368, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29292497

RESUMO

Here, we show that Shh-Cre-mediated deletion of Wntless, the Wnt cargo protein, in mouse posterior limb mesenchyme causes bone syndactyly of the 3rd and 4th digits, resembling the human Malik-Percin type. The Shh descendants gradiently distributed from digit 5 to posterior half of digit 3 in wild-type limbs, however, they abnormally increased in posterior digit 3 in WntlessShh-Cre . WntlessShh-Cre limbs displayed altered expression of hedgehog pathway genes and impaired noncanonical Wnt signaling activity. We further showed that the anterior limb mesenchymal cells in the WlsShh-Cre served as a source of Wnt5a to reorientate the adjacent Wls-lacking Shh lineage cells to move anteriorly and subsequently led to syndactyly, suggesting that aberrant mesenchymal cell movement/condensation may underlie the pathogenesis of syndactyly.


Assuntos
Dedos/anormalidades , Proteínas Hedgehog/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Células-Tronco Mesenquimais/citologia , Receptores Acoplados a Proteínas G/genética , Sindactilia/genética , Dedos do Pé/anormalidades , Animais , Padronização Corporal , Linhagem da Célula , Células Cultivadas , Modelos Animais de Doenças , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Receptores Acoplados a Proteínas G/metabolismo , Via de Sinalização Wnt
6.
Am J Cancer Res ; 7(7): 1463-1475, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28744397

RESUMO

Accumulating studies have demonstrated that non-coding RNAs (ncRNAs), including small non-coding RNAs (small ncRNAs) and long non-coding RNAs (lncRNAs), are involved in tumor growth in lung cancer (LC). However, the specific role of DGCR5 in LC progression is not yet clear. In the present study, we found that DGCR5 was downregulated and miR-1180 was upregulated in the sera and tissues of LC patients and was correlated with poor prognosis. We also found that DGCR5 suppressed proliferation, migration and invasion of LC cell lines H520 and H1299. In addition, a luciferase reporter gene assay was used to investigate the regulatory relationship between DGCR5 and miR-1180. Furthermore, we suggested that DGCR5 inhibited the expression of AKT, GSK-3ß, and ß-catenin by targeting miR-1180. Based on these findings, DGCR5 might serve as a potential target for the development of effective anti-neoplastic therapies in lung cancer.

7.
J Biol Chem ; 292(22): 9409-9419, 2017 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-28438836

RESUMO

The tongue is one of the major structures involved in human food intake and speech. Tongue malformations such as aglossia, microglossia, and ankyloglossia are congenital birth defects, greatly affecting individuals' quality of life. However, the molecular basis of the tissue-tissue interactions that ensure tissue morphogenesis to form a functional tongue remains largely unknown. Here we show that ShhCre -mediated epithelial deletion of Wntless (Wls), the key regulator for intracellular Wnt trafficking, leads to lingual hypoplasia in mice. Disruption of epithelial Wnt production by Wls deletion in epithelial cells led to a failure in lingual epidermal stratification and loss of the lamina propria and the underlying superior longitudinal muscle in developing mouse tongues. These defective phenotypes resulted from a reduction in epithelial basal cells positive for the basal epidermal marker protein p63 and from impaired proliferation and differentiation in connective tissue and paired box 3 (Pax3)- and Pax7-positive muscle progenitor cells. We also found that epithelial Wnt production is required for activation of the Notch signaling pathway, which promotes proliferation of myogenic progenitor cells. Notch signaling in turn negatively regulated Wnt signaling during tongue morphogenesis. We further show that Pax7 is a direct Notch target gene in the embryonic tongue. In summary, our findings demonstrate a key role for the lingual epithelial signals in supporting the integrity of the lamina propria and muscular tissue during tongue development and that a Wnt/Notch/Pax7 genetic hierarchy is involved in this development.


Assuntos
Fator de Transcrição PAX7/metabolismo , Receptores Notch/metabolismo , Língua/embriologia , Via de Sinalização Wnt/fisiologia , Animais , Células Epiteliais/metabolismo , Humanos , Camundongos , Camundongos Knockout , Especificidade de Órgãos , Fator de Transcrição PAX7/genética , Receptores Notch/genética , Células Satélites de Músculo Esquelético/metabolismo
8.
Int Immunopharmacol ; 36: 23-30, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27107369

RESUMO

Garlic is one natural source of organic sulfur containing compounds and has shown promise in the treatment of chronic liver disease. Dietary garlic consumption is inversely correlated with the progression of alcoholic fatty liver (AFL), although the exact underlying mechanisms are not clear. Our previous studies also have shown that diallyl trisulfide (DATS), the primary organosulfur compound from Allium sativum L, displayed anti-lipid deposition and antioxidant properties in AFL. The aim of the present study was to clarify the underlying mechanisms. In the present study, we used the intragastric infusion model of alcohol administration and human normal liver cell line LO2 cultured with suitable ethanol to mimic the pathological condition of AFL. We showed that accumulation of intracellular reactive oxygen species (ROS) was lowered significantly by the administration of DATS, but antioxidant capacity was increased by DATS. Additionally, DATS inhibited hepatocyte apoptosis via down-regulating Bax expression and up-regulating Bcl-2 expression, and attenuated alcohol-induced caspase-dependent apoptosis. More importantly, using iodoacetamide (IAM) to block hydrogen sulfide (H2S) production from DATS, we noted that IAM abolished all the above effects of DATS in ethanol-treated LO2 cells. Lastly, we found DATS could increase the expressions of cystathionine gamma-lyase (CSE) and cystathionine beta-synthase (CBS), the major H2S-producing enzymes. These results demonstrate that DATS protect against alcohol-induced fatty liver via a H2S-mediated mechanism. Therefore, targeting H2S may play a therapeutic role for AFL.


Assuntos
Compostos Alílicos/uso terapêutico , Antioxidantes/uso terapêutico , Fígado Gorduroso Alcoólico/tratamento farmacológico , Alho/imunologia , Hepatócitos/efeitos dos fármacos , Sulfetos/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Etanol , Hepatócitos/patologia , Humanos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Sulfitos/metabolismo
9.
Apoptosis ; 18(2): 135-49, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23247439

RESUMO

Activation of hepatic stellate cells (HSCs) is a pivotal event in the pathogenesis of liver fibrosis. Pharmacological induction of HSC apoptosis could be a promising strategy for fibrosis regression. Natural product tetramethylpyrazine (TMP) exhibits potent antifibrotic activities in vivo. However, the molecular mechanisms remain to be defined. The present study aimed at investigating the anti-proliferative and pro-apoptotic effects of TMP on HSCs and elucidating the underlying mechanisms. Our results demonstrated that TMP had no apparent cytotoxic effects on hepatocytes, but significantly inhibited HSC proliferation and induced cell cycle arrest at the G0/G1 checkpoint. These effects were associated with TMP regulation of cyclin D1, p21, p27 and p53. Furthermore, we found that TMP disrupted mitochondrial functions and led to activation of caspase cascades in HSCs. Mechanistic investigations revealed that TMP selectively blocked the extracellular signal-regulated kinase (ERK) signaling and activated p53, which was required for TMP induction of caspase-dependent mitochondrial apoptosis in HSCs. Autodock simulations predicted that TMP could directly bind to ERK2 with two hydrogen bonds and low energy score, indicating that ERK2 could be a direct target molecule for TMP within HSCs. Moreover, TMP altered expression of some marker proteins relevant to HSC activation. These data collectively revealed that TMP modulation of ERK/p53 signaling led to mitochondrial-mediated and caspase-dependent apoptosis in HSCs in vitro. These studies provided mechanistic insights into the antifibrotic properties of TMP that may be exploited as a potential option for hepatic fibrosis.


Assuntos
Apoptose/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Células Estreladas do Fígado/efeitos dos fármacos , Mitocôndrias/fisiologia , Pirazinas/toxicidade , Proteína Supressora de Tumor p53/fisiologia , Animais , Apoptose/fisiologia , Caspases/fisiologia , Proliferação de Células/efeitos dos fármacos , Células Estreladas do Fígado/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Cirrose Hepática/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Ratos
10.
J Exp Clin Cancer Res ; 28: 107, 2009 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-19638242

RESUMO

BACKGROUND: Liver cancer is a heterogeneous disease in terms of etiology, biologic and clinical behavior. Very little is known about how many genes concur at the molecular level of tumor development, progression and aggressiveness. To explore the key genes involved in the development of liver cancer, we established a rat model induced by diethylnitrosamine to investigate the gene expression profiles of liver tissues during the transition to cirrhosis and carcinoma. METHODS: A rat model of liver cancer induced by diethylnitrosamine was established. The cirrhotic tissue, the dysplasia nodules, the early cancerous nodules and the cancerous nodules from the rats with lung metastasis were chosen to compare with liver tissue of normal rats to investigate the differential expression genes between them. Affymetrix GeneChip Rat 230 2.0 arrays were used throughout. The real-time quantity PCR was used to verify the expression of some differential expression genes in tissues. RESULTS: The pathological changes that occurred in the livers of diethylnitrosamine-treated rats included non-specific injury, fibrosis and cirrhosis, dysplastic nodules, early cancerous nodules and metastasis. There are 349 upregulated and 345 downregulated genes sharing among the above chosen tissues when compared with liver tissue of normal rats. The deregulated genes play various roles in diverse processes such as metabolism, transport, cell proliferation, apoptosis, cell adhesion, angiogenesis and so on. Among which, 41 upregulated and 27 downregulated genes are associated with inflammatory response, immune response and oxidative stress. Twenty-four genes associated with glutathione metabolism majorly participating oxidative stress were deregulated in the development of liver cancer. There were 19 members belong to CYP450 family downregulated, except CYP2C40 upregulated. CONCLUSION: In this study, we provide the global gene expression profiles during the development and progression of liver cancer in rats. The data obtained from the gene expression profiles will allow us to acquire insights into the molecular mechanisms of hepatocarcinogenesis and identify specific genes (or gene products) that can be used for early molecular diagnosis, risk analysis, prognosis prediction, and development of new therapies.


Assuntos
Carcinoma/genética , Perfilação da Expressão Gênica , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , Alquilantes , Animais , Carcinógenos , Carcinoma/patologia , Dietilnitrosamina , Progressão da Doença , Cirrose Hepática/patologia , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Masculino , Modelos Animais , Ratos , Ratos Wistar
11.
BMC Dev Biol ; 9: 21, 2009 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-19284883

RESUMO

BACKGROUND: Cysts of Artemia can remain in a dormant state for long periods with a very low metabolic rate, and only resume their development with the approach of favorable conditions. The post-diapause development is a very complicated process involving a variety of metabolic and biochemical events. However, the intrinsic mechanisms that regulate this process are unclear. RESULTS: Herein we report the specific activation of an AMP-activated protein kinase (AMPK) in the post-diapause developmental process of Artemia. Using a phospho-AMPKalpha antibody, AMPK was shown to be phosphorylated in the post-diapause developmental process. Results of kinase assay analysis showed that this phosphorylation is essential for AMPK activation. Using whole-mount immunohistochemistry, phosphorylated AMPK was shown to be predominantly located in the ectoderm of the early developed embryos in a ring shape; however, the location and shape of the activation region changed as development proceeded. Additionally, Western blotting analysis on different portions of the cyst extracts showed that phosphorylated AMPKalpha localized to the nuclei and this location was not affected by intracellular pH. Confocal microscopy analysis of immunofluorescent stained cyst nuclei further showed that AMPKalpha localized to the nuclei when activated. Moreover, cellular AMP, ADP, and ATP levels in developing cysts were determined by HPLC, and the results showed that the activation of Artemia AMPK may not be associated with cellular AMP:ATP ratios, suggesting other pathways for regulation of Artemia AMPK activity. CONCLUSION: Together, we report evidence demonstrating the activation of AMPK in Artemia developing cysts and present an argument for its role in the development-related gene expression and energy control in certain cells during post-diapause development of Artemia.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Artemia/enzimologia , Embrião não Mamífero/enzimologia , Difosfato de Adenosina/metabolismo , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Artemia/embriologia , Western Blotting , Catálise , Núcleo Celular/enzimologia , Embrião não Mamífero/embriologia , Embrião não Mamífero/metabolismo , Ativação Enzimática , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Imuno-Histoquímica , Microscopia Confocal , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Fosforilação , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Tempo
12.
Hum Pathol ; 40(3): 300-5, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18992912

RESUMO

The aim of this study was to characterize expression of the alpha B-crystallin gene in human hepatocellular carcinomas, to investigate the relationship between expression of this gene and the prognosis of human hepatocellular carcinoma. Real-time polymerase chain reaction, reverse transcriptase-polymerase chain reaction and immunohistochemistry were used to characterize expression of the alpha B-crystallin gene in human hepatocellular carcinoma. Kaplan-Meier survival and Cox regression analyses were performed to evaluate the prognosis of human hepatocellular carcinoma. We characterized alpha B-crystallin gene expression in human hepatocellular carcinoma. Statistical analysis of hepatocellular carcinoma patients showed that patients expressing alpha B-crystallin have different survival rates relative to those not expressing this gene (P = .041). After 18 months, the survival rate of patients expressing alpha B-crystallin declined, but survival in the alpha B-crystallin-negative group remained stable. COX multi-factor analysis showed that alpha B-crystallin (P = .007) and venous invasion (P = .037) were independent prognosis factors for hepatocellular carcinoma. Expression of the alpha B-crystallin gene, which is related with the transferability and invasive capacity of hepatocellular carcinoma cells, can be used as a prognostic indicator in human hepatocellular carcinomas. It may also be involved in the malignant transformation of hepatocytes.


Assuntos
Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Hepáticas/genética , Cadeia B de alfa-Cristalina/genética , Adulto , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Feminino , Técnica Direta de Fluorescência para Anticorpo , Humanos , Técnicas Imunoenzimáticas , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , RNA Neoplásico/análise , Taxa de Sobrevida , Cadeia B de alfa-Cristalina/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-17400496

RESUMO

DNA methyltransferase 2 (Dnmt2) is a dual-specificity DNA methyltransferase, which contains a weak DNA methyltransferase and novel tRNA methyltransferase activity. However, its biological function is still enigmatic. To elucidate the expression profiles of Dnmt2 in Artemia franciscana, we isolated the gene encoding a Dnmt2 from A. franciscana and named it as AfDnmt2. The cDNA of AfDnmt2 contained a 1140-bp open reading frame that encoded a putative Dnmt2 protein of 379 amino acids exhibiting 32% approximately 39% identities with other known Dnmt2 homologs. This is the first report of a DNA methyltransferase gene in Crustacean. By using semi-quantitative RT-PCR, AfDnmt2 was found to be expressed through all developmental stages and its expression increased during resumption of diapause cysts development. Southern blot analysis indicated the presence of multiple copies of AfDnmt2 genes in A. franciscana.


Assuntos
Artemia/genética , DNA (Citosina-5-)-Metiltransferases/genética , Expressão Gênica , Sequência de Aminoácidos , Análise de Variância , Animais , Sequência de Bases , Southern Blotting , Primers do DNA , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA
14.
Stress ; 10(1): 53-63, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17454967

RESUMO

AMP-activated protein kinase (AMPK) plays a central role in maintaining the energy balance of organisms under physiological and environmental stresses. Here two AMPK alpha subunit gene transcripts (named Afr-AMPKalpha1 and Afr-AMPKalpha2) from Artemia franciscana were isolated and gene expression was characterized by semiquantitive reverse transcription-polymerase chain reaction (RT-PCR). Afr-AMPKalpha1 was differentially expressed during Artemia developmental stages as well as in response to stresses, such as heat-shock, starvation and a hyperosmotic environment. Afr-AMPKalpha1 mRNA expression in adult Artemia decreased under heat shock, but not in a time- and temperature-dependent manner. By contrast, the transcript sharply decreased in heat-shocked cysts in a time-dependent manner. Under hyperosmotic stress, however, the mRNA level in adults first declined and then increased with prolonged exposure. In the case of starvation, the gene expression in adults decreased and was undetectable after day 9. In addition, Afr-AMPKalpha2 mRNA expression was too low to be detected without nested PCR. Southern blot analysis, moreover, indicated AMPK alpha subunit was present in multiple copies in the Artemia genome. Furthermore, our results demonstrate that the Afr-AMPKalpha1 mRNA level sharply decreases in Artemia carrying diapause-destined embryos and this indicates the possibility that Afr-AMPKalpha1 is involved in determining the reproductive mode in Artemia.


Assuntos
Envelhecimento/metabolismo , Artemia/embriologia , Artemia/enzimologia , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Estresse Fisiológico/enzimologia , Proteínas Quinases Ativadas por AMP , Sequência de Aminoácidos , Animais , Artemia/genética , Sequência de Bases , Southern Blotting , Embrião não Mamífero/metabolismo , Feminino , Expressão Gênica , Transtornos de Estresse por Calor/complicações , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Dados de Sequência Molecular , Pressão Osmótica , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inanição/complicações , Estresse Fisiológico/etiologia , Técnicas de Cultura de Tecidos
15.
Cell Stress Chaperones ; 9(3): 313-23, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15544169

RESUMO

Two complementary deoxyribonucleic acid (cDNA) clones encoding 2 different 70-kDa heat shock proteins (HSPs) were isolated from the prawn Macrobrachium rosenbergii. The cDNA clones were 2448 and 2173 bp in length and contained 1950- and 1734-bp open reading frames (ORFs), respectively. The ORFs encoded 649- and 577-amino acid polypeptides, which were named Mar-HSC70 and Mar-HSP70, respectively, according to the sequence identities with other known HSC70s and HSP70s and based on their inducibility in response to heat shock stress (at 35 degrees C). Genomic DNA sequence analysis revealed no introns in either gene. The major structural differences between the 2 proteins were a 60-amino acid segment and a 14-amino acid segment present in the N-terminal and C-terminal, respectively, of Mar-HSC70 that were not found in Mar-HSP70. Northern blotting and semiquantitative reverse transcription-polymerase chain reaction analyses indicated that the Mar-HSP70 gene was expressed under heat shock (35 degrees C) stress in a non-tissue-specific manner. In contrast, Mar-HSC70 messenger ribonucleic acid was constitutively expressed in every tissue except muscle, and its expression in response to heat shock (at 35 degrees C) changed only in muscle.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Resposta ao Choque Térmico/genética , Palaemonidae/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Sequência Conservada , DNA Complementar/análise , DNA Complementar/genética , Feminino , Expressão Gênica/genética , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/isolamento & purificação , Íntrons/genética , Masculino , Dados de Sequência Molecular , Músculos/metabolismo , Palaemonidae/genética , Filogenia , Estrutura Terciária de Proteína/genética , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
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