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3.
Eur Rev Med Pharmacol Sci ; 24(7): 3959-3964, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32329872

RESUMO

OBJECTIVE: The aim of this study was to explore the relationship between serum MALAT1 level and clinical features of elderly patients with severe pneumonia and its impact on patients' survival. PATIENTS AND METHODS: A total of 150 elderly patients with severe pneumonia were enrolled in this study. According to patients' prognosis, enrolled subjects were divided into two groups, including death group (n=63) and survival group (n=87). The clinical data and indicators of subjects were collected, and χ2 and t-tests were used for statistical analysis. MALAT1 expression in the serum of all subjects was examined through the qPCR assay. Meanwhile, the predictive value of MALAT1 for patient death was assessed by the receiver operating characteristic curve (ROC). RESULTS: PT, APTT, DD, APACHE II scores, and MODS scores in death group were remarkably higher, while HB, HCT, TT, and PaO2/FiO2 were conversely lower than those in survival group (p<0.05). QRT-PCR results revealed significantly increased MALAT1 expression in death group when compared with survival group, especially in those patients with a history of smoking and COPD (p<0.05). In addition, ROC analysis confirmed the predictive value of MALAT1 for the prognosis of elderly patients with severe pneumonia. CONCLUSIONS: MALAT1 is highly expressed in the serum of elderly patients with severe pneumonia. Furthermore, it may serve as a marker for the prediction of survival of these patients.


Assuntos
Pneumonia/genética , RNA Longo não Codificante/genética , Idoso , Feminino , Humanos , Masculino , Pneumonia/sangue , Pneumonia/metabolismo , RNA Longo não Codificante/sangue , RNA Longo não Codificante/metabolismo , Índice de Gravidade de Doença , Taxa de Sobrevida
5.
Eur Rev Med Pharmacol Sci ; 23(24): 11025-11031, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31858574

RESUMO

OBJECTIVE: To systematically review the efficacy and safety of tranexamic acid (TXA) in reducing blood transfusion and total blood loss in patients undergoing orthopaedic trauma surgery. MATERIALS AND METHODS: A systematic literature search was performed using PubMed, Embase and Cochrane Library databases. The search time was incepted to February 2019. Two reviewers independently screened literature, extracted data, and assessed risk of bias. Then, meta-analysis was performed using RevMan 5.3. RESULTS: A total of 10 studies were included, with 936 patients. The pooled results indicated that TXA group was superior to control group in the total blood loss [MD=-157.61, 95%CI (-250.09, -65.13), p=0.0008], blood transfusion [OR=0.59, 95%CI (0.43, 0.81), p=0.001], and the wound complications [OR=0.59, 95%CI (0.43, 0.81), p=0.001]. There was no significant difference in risk of thromboembolic events [OR=1.27, 95%CI (0.78, 2.12), p=0.35] and the mortality [OR=0.79, 95%CI (0.35, 1.78), p=0.57] between TXA and control group. CONCLUSIONS: TXA could effectively reduce blood transfusion, total blood loss, and wound complications in patients undergoing orthopedic trauma surgery. Furthermore, TXA does not significantly increase the incidence of thromboembolic events and mortality. Due to the limited quality of the included studies, more high-quality works are required to verify the above conclusions.


Assuntos
Antifibrinolíticos/uso terapêutico , Ácido Tranexâmico/uso terapêutico , Ferimentos e Lesões/tratamento farmacológico , Antifibrinolíticos/efeitos adversos , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue , Humanos , Procedimentos Ortopédicos/efeitos adversos , Ácido Tranexâmico/efeitos adversos , Ferimentos e Lesões/complicações , Ferimentos e Lesões/cirurgia
6.
Artigo em Chinês | MEDLINE | ID: mdl-31163529

RESUMO

Objective:To explore the relationships between glucocorticoid (GC) sensitivity and the prognosis of refractory sudden sensorineural hearing loss (SSNHL), and to analyze the related factors being affected the prognosis of SSNHL. Method:Ninety-one refractory SSNHL patients were enrolled in the present investigation. Peripheral blood mononuclear cells (PBMCs) from the refractory SSNHL were extracted to conduct GC proliferation dexamethasone (DEX) inhibition experiments. All patients accepted comprehensive treatment with methylprednisolone. Result:Total effective rate was 40.66% in refractory SSNHL patients. Gender, number of affected ear, age, accompanying with vertigo, tinnitus or not and the procedure of methylprednisolone treatment were irrelevant to the efficacy. Only the inhibitory rate of DEX and the time from onset to visit were related to GC treatment effect, especially for inhibitory rate of DEX. The DEX inhibition rate of the effective group was higher than that of the ineffective group. Conclusion:DEX inhibition rate can predict GC sensitivity and prognosis of SSNHL. GC sensitivity and the time from onset to treatment are two important factors affecting the prognosis of refractory SSNHL patients..


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Anti-Inflamatórios/administração & dosagem , Dexametasona/administração & dosagem , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Súbita/complicações , Perda Auditiva Súbita/diagnóstico , Humanos , Leucócitos Mononucleares , Prognóstico , Zumbido , Vertigem
7.
Eur Rev Med Pharmacol Sci ; 23(10): 4341-4347, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31173307

RESUMO

OBJECTIVE: To study the correlation between the plasma long non-coding RNA (lncRNA) maternally expressed gene 3 (MEG3) and the levels of inflammatory cytokines in patients with traumatic brain injury (TBI) and to evaluate its prognosis to screen new biological targets for the diagnosis and treatment of TBI. PATIENTS AND METHODS: 40 patients with TBI (TBI group) and 40 healthy people (control group) were collected and venous blood was drawn. The plasma MEG3 in subjects was quantitatively analyzed via quantitative Polymerase Chain Reaction (qPCR). Moreover, the levels of inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), IL-6, and IL-8] in plasma in each group were detected via enzyme-linked immunosorbent assay (ELISA). Finally, the correlation analysis was performed for the MEG3 expression level and inflammatory cytokine levels in patients with TBI. Patients were divided into high-expression MEG3 group and low-expression MEG3 group, high-level inflammatory cytokine group and low-level inflammatory cytokine group according to the median, followed by prognosis evaluation. The MEG3 expression level in TBI group was significantly decreased compared to that in control group, and the levels of inflammatory cytokines in plasma, including TNF-α, IL-1ß, IL-6, and IL-8, were significantly higher than in control group. RESULTS: The results of the correlation analysis showed that the expression level of plasma MEG3 had a significantly negative correlation with the level of each inflammatory cytokine. The prognostic analysis revealed that the prognosis of patients with high MEG3 expression level and low inflammatory cytokine levels was good, while it was poor in patients with low MEG3 expression level and high inflammatory cytokine levels; the difference was significant. In patients with TBI, the expression level of plasma MEG3 is decreased, while the inflammatory cytokine levels are increased, and there is a significantly negative correlation between the two items. CONCLUSIONS: The prognosis of patients with high MEG3 expression level and low inflammatory cytokine levels is good so MEG3 and inflammatory cytokines can be used as biomarkers for diagnosis and treatment of TBI, improving the prognosis of patients.


Assuntos
Lesões Encefálicas Traumáticas/sangue , Lesões Encefálicas Traumáticas/patologia , Mediadores da Inflamação/sangue , Inflamação/sangue , RNA Longo não Codificante/sangue , Adulto , Idoso , Biomarcadores , Lesões Encefálicas Traumáticas/genética , Citocinas/sangue , Feminino , Humanos , Inflamação/genética , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Longo não Codificante/genética , Adulto Jovem
8.
Eur Rev Med Pharmacol Sci ; 23(4): 1418-1427, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30840262

RESUMO

OBJECTIVE: Long non-coding RNA DBH-AS1 (DBH-AS1) has emerged as a novel regulator in cancer initiation and progression of several tumors. However, the expression of DBH-AS1 in osteosarcoma and its effect on the tumorigenesis of osteosarcoma are unclear. The purpose of this study was to determine the role of DBH-AS1 in osteosarcoma progression. PATIENTS AND METHODS: The expression level of DBH-AS1 in 119 pairs of osteosarcoma tissues and five cell lines was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The association of DBH-AS1 expression with clinicopathological factors and prognosis was also analyzed. Cell proliferation was measured by Cell Counting Kit-8 (CCK-8), EdU and cell colony formation assays and apoptosis in MG63 and U2OS cells was examined by flow cytometry. Following that, transwell invasion and wound-healing assays were used to explore cell migration and invasion, respectively. The expression of the PI3K/Akt pathway-related proteins was examined by Western blot analysis. RESULTS: We observed that DBH-AS1 was distinctly overexpressed in osteosarcoma tissue and cells, and associated with lymph node status and metastasis status. Osteosarcoma patients with a higher DBH-AS1 expression showed significantly poorer overall survival than those with lower DBH-AS1 expression. Multivariate analysis demonstrated that high DBH-AS1 expression was an independent poor prognostic factor for osteosarcoma patients. Functional assays revealed that knockdown of DBH-AS1 inhibited cell proliferation, migration and invasion, while promoted apoptosis in osteosarcoma. Moreover, suppression of DBH-AS1 could inhibit the activation of the PI3K/Akt pathway, which was demonstrated by examining the expression levels of p-PI3K and p-Akt. CONCLUSIONS: Our data first reported that DBH-AS1 may act as an oncogenic lncRNA by modulating the PI3K/Akt pathway in osteosarcoma, which may serve as a candidate prognostic biomarker and target for new therapies in osteosarcoma.


Assuntos
Neoplasias Ósseas/patologia , Osteossarcoma/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Longo não Codificante/metabolismo , Idoso , Apoptose , Neoplasias Ósseas/genética , Neoplasias Ósseas/mortalidade , Linhagem Celular Tumoral , Movimento Celular , Progressão da Doença , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Osteossarcoma/genética , Osteossarcoma/mortalidade , Fosfatidilinositol 3-Quinases/genética , Prognóstico , Proteínas Proto-Oncogênicas c-akt/genética , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Taxa de Sobrevida
9.
Leukemia ; 32(3): 703-711, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29135973

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma. Histone deacetylase 6 (HDAC6) is frequently altered in DLBCL and inhibition of HDAC6 has potent anti-tumor effects in vitro and in vivo. We profiled miRNAs that altered in the HDAC6 knockdown DLBCL cells with NanoString nCounter assay and identified microRNA-27b (miR-27b) as the most significantly increased miRNA. We validated decreased expression of miR-27b in DLBCL tissues, and we found that low expression of miR-27b was associated with poor overall survival of patients with DLBCL. In addition, forced expression of miR-27b suppressed DLBCL cell viability and proliferation in vitro, and inhibited tumor growth in vivo. Mechanistically, Rel A/p65 is found to negatively regulate miR-27b expression, and its acetylation and block of nuclear translocalization caused by HDAC6 inhibition significantly elevates miR-27b expression. Furthermore, miR-27b targets MET and thus represses the MET/PI3K/AKT pathway. These findings highlight an important role of miR-27b in the development of DLBCL and uncover a HDAC6-Rel A/p65-miR-27b-MET signaling pathway. Elevating miR-27b through HDAC6 inhibition would be a promising strategy for DLBCL treatment.


Assuntos
Apoptose/genética , Regulação Neoplásica da Expressão Gênica , Desacetilase 6 de Histona/metabolismo , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-met/genética , Biomarcadores , Linhagem Celular Tumoral , Proliferação de Células , Perfilação da Expressão Gênica , Humanos , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/patologia , Prognóstico , Interferência de RNA , Transdução de Sinais , Fator de Transcrição RelA/metabolismo
10.
Zhonghua Xue Ye Xue Za Zhi ; 38(1): 50-54, 2017 Jan 14.
Artigo em Chinês | MEDLINE | ID: mdl-28219226

RESUMO

Objectives: To explore the effects of 13-cis-retinoic acid (13cRA) alone or combined with interferonα-2b (IFNα-2b) for the inhibition of cell growth and apoptosis induction of mantle cell lymphoma cell lines Jeko-1 cells. Methods: Jeko-1 cells were treated by different concentrations of 13cRA alone or combined with IFN-α2b. CCK-8 was used to measure the inhibition effects by different treatments. Cell cycles were analyzed by flow cytometry. Effects on apoptosis were assessed by staining of Annexin Ⅴ/PI. And the levels of Cyclin D1, caspase-9 and Rb proteins were measured by Western blot method. Results: 13cRA alone at different doses and its combination with IFNα-2b inhibited Jeko-1 cells growth and induced apoptosis, but the combination had higher inhibition potential and significant apoptosis rate (P<0.05) . The growth inhibition and apoptosis induction in Jeko-1 cells increased significantly with the elevation of drugs concentration and treating duration (P<0.05) . As well as the percentage of Jeko-1 cells at G(1)/G(2) phases increased (P<0.05) and cells at S phase decreased (P<0.05) , the levels of Cyclin D1 and Rb decreased with elimination caspase-9. Conclusion: 13cRA, IFN-α2b and their combined administration inhibited cells growth and induced apoptosis, decreased the cell populations at S phase and blocked the cells at G(1)/G(2) phase. Combination of the drugs may have a cooperated action. The therapeutic synergistic effects of 13cRA and IFN-α2b were assumed to lower the expression of Cyclin D1 and Rb proteins, and induce apoptosis by activating caspase-9 pathway.


Assuntos
Linfoma de Célula do Manto , Apoptose , Caspase 9 , Linhagem Celular Tumoral , Linhagem da Célula , Proliferação de Células , Ciclina D1 , Humanos , Interferon alfa-2 , Interferon-alfa , Isotretinoína , Proteínas Recombinantes
11.
Zhonghua Xue Ye Xue Za Zhi ; 37(9): 784-789, 2016 Sep 14.
Artigo em Chinês | MEDLINE | ID: mdl-27719722

RESUMO

Objective: To determine the anti-tumor effects of 13-cis-retinoic acid (13cRA) combined with interferonα-2b (IFNα-2b) in mantle cell lymphoma (MCL) animal model. Methods: The animal model of MCL was established by introducing Jeko-1 cell line into severe combined immunodeficiency disease mice. The successfully tumor-developed mice were assigned to different groups treated with negative control group (solvents), 13cRA (high dose: 200mg/kg; middle dose: 100mg/kg; low dose: 50 mg/kg) alone, IFNα-2b alone or combination of different dose of 13cRA with IFNα-2b, and positive control group (bortezomib, rituximab, cyclophosphamide), respectively. Variations of tumor volume were observed regularly. The relative tumor proliferation rate and tumor inhibition rate were calculated. Immunohistochemistry stain was used to detect the Ki-67 expression and TUNEL was applied to measure the apoptosis of tumor cells. Furthermore, the levels of Cyclin D1, caspase 9 and Rb protein were measured by Western-blot method. Results: ① The relative tumor proliferation rates (T/C%)were 30%, 37%, 32% and 33% in middle dose, high dose groups of 13cRA as well as their combination with IFN α-2b, respectively. ② Comparing with the negative control, both 13cRA at different doses and its combination with IFNα-2b remarkably inhibited the tumor growth (P<0.05), while no statistic significance existed in different dose group of 13cRA. IFN-α 2b alone didn't demonstrate the tumor-inhibition effects (P>0.05). Middle dose of 13cRA and its combination with IFN-α-2b demonstrated relatively high tumor-inhibition effects (59.2% and 62.6% respectively), which were similar to the effects in positive control (69.4%). ③ There was no statistic difference of Ki-67 in each experimental group. ④ Comparing with negative control group, all doses of 13cRA and their combinations with IFNα-2b remarkably increased the apoptosis (P<0.05), similar to the positive control group (P>0.05). However, IFNα-2b alone didn' t promote the apoptosis of tumor tissue (P=0.098). ⑤ Comparing with negative control group, IFNα-2b combined with each dose of 13cRA significantly decreased the levels of cycling D1 and procaspase-9, while increased the level of cleaved caspase-9 (P<0.05), which were similar to the positive control group (P>0.05). Nevertheless, 13cRA alone didn't demonstrate such effects. Conclusion: In the MCL animal model, IFNα-2b alone showed no effects, but combined with IFNα-2b, 13cRA displayed anti-tumor effects at different doses. The anti-tumor mechanism of 13cRA combined with IFNα-2b was probably down-regulation of the cyclin D1 expression, inhibition of cell proliferation and induction of apoptosis by activating caspase-9.


Assuntos
Interferon-alfa/uso terapêutico , Isotretinoína/uso terapêutico , Linfoma de Célula do Manto/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Bortezomib/administração & dosagem , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Ciclina D1/efeitos dos fármacos , Ciclina D1/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Humanos , Camundongos
12.
Oncogene ; 29(20): 2996-3009, 2010 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-20228837

RESUMO

To identify more therapeutic targets and clarify the detailed mechanisms of Pseudomonas aeruginosa-mannose-sensitive hemagglutinin (PA-MSHA) on breast cancer cells both in vitro and in vivo. PA-MSHA was administered to epidermal growth factor receptor (EGFR)-positive human breast cancer cell lines MDA-MB-231HM and MDA-MB-468 in vitro and to mice bearing tumor xenografts. The mannose cocultured test was used to detect the effect of mannose on PA-MSHA-induced cell proliferation, cell cycle arrest, apoptosis, and EGFR pathway signaling. We found that cells stimulated with PA-MSHA exhibited a downregulation of EGFR signaling. The addition of mannose partially inhibited the PA-MSHA-stimulated cell anti-proliferative effect, cell apoptosis, cell cycle arrest, activation of apoptosis-associated caspases, and even downregulation of the EGFR signaling pathway. In vivo, PA-MSHA treatment significantly suppressed mammary tumorigenesis in xenografts in mice and decreased lung metastasis in MDA-MB-231HM cell-transplanted mice. Tumor sample analyses confirmed inhibition of the EGFR pathway in the PA-MSHA-treated mice. In conclusion, this study showed that the involvement of the mannose-mediated EGFR pathway has a critical function in the preclinical rationale for the development of PA-MSHA for the treatment of human breast cancer. It also suggests the potentially beneficial use of PA-MSHA in adjuvant therapy for breast tumors with EGFR overexpression.


Assuntos
Neoplasias da Mama/prevenção & controle , Receptores ErbB/metabolismo , Fímbrias Bacterianas/metabolismo , Hemaglutininas/farmacologia , Neoplasias Pulmonares/prevenção & controle , Manose/metabolismo , Pseudomonas aeruginosa/metabolismo , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Feminino , Citometria de Fluxo , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais
13.
Eur J Surg Oncol ; 35(9): 921-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19233602

RESUMO

BACKGROUND: Sentinel lymph node biopsy (SLNB) has become an alternative procedure of axillary lymph node dissection (ALND) with a lower risk of significant operative morbidity. The primary aim of the present study was to evaluate the morbidity and quality-of-life (QoL) after SLNB or ALND. The second aim was to analyze whether the number of SLNs removed was associated with an increased incidence of postoperative morbidity. METHODS: From Apr-2006 to Aug-2007, 140 patients treated with SLNB and 81 patients treated with ALND were enrolled in the study. Patients' data were collected preoperatively and at 1, 6, and 12 months after operation. Measurement of arm volume and shoulder function, evaluation of subjective sensory abnormality of both arms and chest wall were performed at every follow-up visit. Besides, patients were required to fill out the simplified Chinese version of the functional assessment of cancer therapy-breast questionnaire at 12 months after operation. RESULTS: Patients treated with SLNB suffered less morbidity compared with ALND. Elevated body mass index and ALND procedure were independent risk factors associated with postoperative lymphedema. Moreover, patients treated with wide local excision or SLNB had better QoL compared with those treated with mastectomy or ALND. No relationship was observed between the number of SLNs and the morbidity or QoL. CONCLUSION: SLNB is associated with a better QoL and less morbidity compared with ALND regardless of the number of SLNs in Chinese women with breast cancer. To limit the number of SLNs less than five did not show any evidence to reduce morbidity.


Assuntos
Neoplasias da Mama/patologia , Excisão de Linfonodo/efeitos adversos , Linfedema/prevenção & controle , Qualidade de Vida , Biópsia de Linfonodo Sentinela/efeitos adversos , Adulto , Idoso , Braço , Axila , Neoplasias da Mama/cirurgia , China/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Modelos Logísticos , Linfedema/epidemiologia , Linfedema/etiologia , Mastectomia/efeitos adversos , Pessoa de Meia-Idade , Análise Multivariada , Recuperação de Função Fisiológica , Fatores de Risco , Ombro , Parede Torácica
14.
Plant Physiol ; 115(2): 397-407, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12223815

RESUMO

The E1 promoter fragment (-249 to -203) is one of three auxin-response elements (AuxREs) in the soybean (Glycine max L.) GH3 promoter (Z.-B. Liu, T. Ulmasov, X. Shi, G. Hagen, T.J. Guilfoyle [1994] Plant Cell 6: 645-657). Results presented here further characterize and delimit the AuxRE within the E1 fragment. The E1 fragment functioned as an AuxRE in transgenic tobacco (Nicotiana tabacum L.) plants, as well as in transfected protoplasts. The AuxRE within E1 contains a G-box, and this G-box was used to clone a G-box-binding factor (GBF) from soybean (SGBF-2). This 45-kD GBF contains an N-terminal proline-rich domain and a C-terminal basic/leucine zipper DNA-binding domain. Gel-mobility shift assays were used to characterize the binding specificity of SGBF-2. Antiserum raised against recombinant SGBF-2 was used to further characterize SGBF-2 and antigenically related GBFs in soybean nuclear extracts. Co-transfection assays with effector and reporter plasmids in carrot (Daucus carota L.) protoplasts indicated that the N-terminal proline-rich domain of SGBF-2 functioned as a repression domain in both basal and auxin-inducible transcription.

15.
Plant Cell ; 7(10): 1611-23, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7580254

RESUMO

The auxin-responsive soybean GH3 gene promoter is composed of multiple auxin response elements (AuxREs), and each AuxRE contributes incrementally to the strong auxin inducibility to the promoter. Two independent AuxREs of 25 bp (D1) and 32 bp (D4) contain the sequence TGTCTC. Results presented here show that the TGTCTC element in D1 and D4 is required but not sufficient for auxin inducibility in carrot protoplast transient expression assays. Additional nucleotides upstream of TGTCTC are also required for auxin inducibility. These upstream sequences showed constitutive activity and no auxin inducibility when part or all of the TGTCTC element was mutated or deleted. In D1, the constitutive element overlaps the 5' portion of TGTCTC; in D4, the constitutive element is separated from TGTCTC. An 11-bp element in D1, CCTCGTGTCTC, conferred auxin inducibility to a minimal cauliflower mosaic virus 35S promoter in transgenic tobacco seedlings as well as in carrot protoplasts (i.e., transient expression assays). Both constitutive elements bound specifically to plant nuclear proteins, and the constitutive element in D1 bound to a recombinant soybean basic leucine zipper transcription factor with G-box specificity. To demonstrate further the composite nature of AuxREs and the ability of the TGTCTC element to confer auxin inducibility, we created a novel AuxRE by placing a yeast GAL4 DNA binding site adjacent to the TGTCTC element. Expression of a GAL4-c-Rel transactivator in the presence of this novel AuxRE resulted in auxin-inducible expression. Our results indicate that at least some AuxREs have a composite structure consisting of a constitutive element adjacent to a conserved TGTCTC element that confers auxin inducibility.


Assuntos
Genes de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/farmacologia , Animais , Sequência de Bases , DNA de Plantas/genética , DNA de Plantas/metabolismo , Dados de Sequência Molecular , Mutação , Proteínas Nucleares/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Plantas Tóxicas , Regiões Promotoras Genéticas/efeitos dos fármacos , Glycine max/efeitos dos fármacos , Glycine max/genética , Glycine max/metabolismo , Nicotiana/genética
16.
Plant Physiol ; 106(1): 37-43, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7972520

RESUMO

The soybean SAUR (Small Auxin-Up RNA) genes are transcriptionally induced by exogenous auxins within a few minutes after hormone application. This response is specifically induced by auxins primarily in epidermal and cortical cells within elongation zones of hypocotyls and epicotyls. We have previously shown that an 832-bp soybean SAUR promoter/beta-glucuronidase (GUS) reporter gene fusion is responsive to auxin in transgenic tobacco plants (Y. Li, G. Hagen, T.J. Guilfoyle [1991] Plant Cell 3: 1167-1175). Similar results were obtained with an 868-bp SAUR 15A promoter-GUS reporter gene in transgenic tobacco (Y. Li, unpublished results). We have now analyzed a soybean SAUR 15A promoter in transgenic tobacco plants using 5' unidirectional deletions, internal deletions and mutations, and gain-of-function assays with a minimal cauliflower mosaic virus 35S promoter. Our results indicate that the distal upstream element/NdeI restriction endonuclease site element (NDE) (B.A. McClure, G. Hagen, C.S. Brown, M.A. Gee, T.J. Guilfoyle [1989] Plant Cell 1: 229-239) in the SAUR 15A promoter is necessary and sufficient for auxin induction. Our results also show that the 30-bp NDE portion of this element is responsible for most, if not all, of the auxin inducibility of the SAUR 15A promoter. The NDE contains two adjacent sequences, TGTCTC and GGTCCCAT, which have been previously identified as putative auxin-responsive elements. We propose that these elements might function independently or together, possibly with an additional element(s), to confer auxin inducibility to the SAUR promoters.


Assuntos
Glycine max/genética , Regiões Promotoras Genéticas , Sequência de Bases , Clonagem Molecular , DNA de Plantas/genética , Deleção de Genes , Genes de Plantas/efeitos dos fármacos , Genes Reporter , Ácidos Indolacéticos/farmacologia , Dados de Sequência Molecular , Mutação , Plantas Geneticamente Modificadas , Plantas Tóxicas , Regiões Promotoras Genéticas/efeitos dos fármacos , Glycine max/efeitos dos fármacos , Nicotiana/genética
17.
Plant Cell ; 6(5): 645-57, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8038604

RESUMO

The soybean GH3 gene is transcriptionally induced in a wide variety of tissues and organs within minutes after auxin application. To determine the sequence elements that confer auxin inducibility to the GH3 promoter, we used gel mobility shift assays, methylation interference, deletion analysis, linker scanning, site-directed mutagenesis, and gain-of-function analysis with a minimal cauliflower mosaic virus 35S promoter. We identified at least three sequence elements within the GH3 promoter that are auxin inducible and can function independently of one another. Two of these elements are found in a 76-bp fragment, and these consist of two independent 25- and 32-bp auxin-inducible elements. Both of these 25- and 32-bp auxin-inducible elements contain the sequence TGTCTC just upstream of an AATAAG. An additional auxin-inducible element was found upstream of the 76-bp auxin-inducible fragment; this can function independently of the 76-bp fragment. Two TGA-box or Hex-like elements (TGACGTAA and TGACGTGGC) in the promoter, which are strong binding sites for proteins in plant nuclear extracts, may also elevate the level of auxin inducibility of the GH3 promoter. The multiple auxin-inducible elements within the GH3 promoter contribute incrementally to the overall level of auxin induction observed with this promoter.


Assuntos
Genes de Plantas , Glycine max/genética , Ácidos Indolacéticos/farmacologia , Regiões Promotoras Genéticas , Agrobacterium tumefaciens/genética , Sequência de Bases , Caulimovirus/genética , Primers do DNA , Expressão Gênica , Glucuronidase/biossíntese , Glucuronidase/genética , Dados de Sequência Molecular , Mutagênese Insercional , Mutagênese Sítio-Dirigida , Plantas Geneticamente Modificadas , Plantas Tóxicas , Reação em Cadeia da Polimerase , Deleção de Sequência , Nicotiana/genética , Transcrição Gênica , Transfecção
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