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1.
Gene ; 735: 144407, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32007582

RESUMO

Krüppel-like factor13 (klf13), a member of the Krüppel-like factor family, plays a vital role in cell proliferation and differentiation. When sea cucumber Apostichopus japonicus is attacted by predators, it can spit viscera in order to escape attack, and then complete the intestine regeneration process within 15 days. However, the potential role of klf13 from A. japonicus (Aj-klf13) in the intestine regeneration of sea cucumber A. japonicus still remains unknown. In present paper, the full-length cDNA of klf13 gene from A. japonicus was cloned by RACE techniques, and it was composed of 2496 bp, including a 245 bp 5' UTR, a 1396 bp 3' UTR and a 855 bp open reading frame, which encoded a polypeptide of 284 amino acids and C2H2 zinc finger domains. The expression level of Aj-klf13 showed an increasing trend in intestine regeneration process of sea cucumber, and it reached the highest at 6 days, returning to the normal at 15 days. By western blot, the expression level of Aj-KLF13 protein was basically consistent with that of Aj-klf13 gene. The expression locations of protein by immunofluorescence indicated that Aj-KLF13 was widely expressed in the normal physiological state and intestine regeneration process of sea cucumbers, which was in the nucleus. There was tissue specificity of the protein, which was mainly distributed in luminal epithelium and coelomic epithelium. These results indicate that Aj-klf13 plays a crucial role in the intestine regeneration process of sea cucumber A. japonicus.


Assuntos
Intestinos/fisiologia , Fatores de Transcrição Kruppel-Like/genética , Regeneração , Stichopus/genética , Animais , Clonagem Molecular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Mucosa Intestinal/metabolismo , Fatores de Transcrição Kruppel-Like/química , Fatores de Transcrição Kruppel-Like/metabolismo , Stichopus/metabolismo
3.
Virchows Arch ; 476(1): 97-108, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31696361

RESUMO

Rhabdomyosarcomas are malignancies associated with a rhabdomyoblastic phenotype which can be demonstrated morphologically or by immunohistochemistry for MYOD1 and myogenin. Rhabdomyosarcomas are currently subdivided into 4 types in the 2013 WHO classification of tumors of soft tissue and bone, including embryonal rhabdomyosarcoma, alveolar rhabdomyosarcoma, spindle cell/sclerosing rhabdomyosarcoma, and pleomorphic rhabdomyosarcoma. Recent studies have significantly impacted this classification with the emergence of three distinct new subtypes of rhabdomyosarcomas, namely rhabdomyosarcoma with MYOD1 mutations, rhabdomyosarcoma with TFCP2 fusions, and rhabdomyosarcoma with VGLL2/NCOA2 fusions. Although all these tumors share the terminology "rhabdomyosarcoma," their morphology, clinical behavior, and underlying molecular alterations are dramatically different. Finally, the presence of a rhabdomyoblastic phenotype within a tumor is by no means a diagnostic of a rhabdomyosarcoma, as this may be seen in many other mesenchymal malignancies, such as mesenchymal chondrosarcomas, malignant peripheral nerve sheaths tumors, and biphenotypic sinonasal sarcomas. In this review, we present the main clinical, morphological, and molecular features of these tumors and discuss the evolution of the current classification.


Assuntos
Rabdomiossarcoma/patologia , Predisposição Genética para Doença , Humanos , Fatores de Transcrição Kruppel-Like/genética , Proteína EWS de Ligação a RNA/genética , Proteínas Repressoras/genética , Rabdomiossarcoma/classificação , Rabdomiossarcoma/genética
4.
Ann Hematol ; 99(1): 23-29, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31776727

RESUMO

Hemoglobin (Hb) F has a modulatory effect on the clinical phenotype of ß-thalassemia disease. High expression of Hb F in Hb E-related disorders has been noted, but the mechanism is not well understood. We have examined the association of a novel SNP rs11759328 on ARHGAP 18 gene and other known modulators with a variability of Hb F in Hb E-related disorders. Genotyping of SNP rs11759328 (G/A) was performed based on high-resolution melting analysis. The rs11759328 (A allele) was shown to be significantly associated with Hb F levels (p < 0.05) in heterozygous and homozygous Hb E. High levels of Hb F in both heterozygous and homozygous Hb E were also found to be associated with SNPs in the study of other modifying genes including KLF 1 mutation, rs7482144 (Gγ-XmnI), rs4895441, rs9399137 of (HBS1L-MYB), and rs4671393 (BCL11A). Multivariate analysis showed that KLF1 mutation and SNP rs11759328 (GA) (ARHGAP18) modulated Hb F expression in heterozygous Hb E. For homozygous Hb E, this was found to be related to five modifying factors, i.e., KLF1 mutation, rs4895441 (GG), rs9399137 (CC), rs4671393 (AA), and rs4671393 (GA). These results indicate that a novel SNP rs11759328 is a genetically modifying factor associated with increased Hb F in Hb E disorder.


Assuntos
Hemoglobina Fetal/biossíntese , Proteínas Ativadoras de GTPase/genética , Regulação da Expressão Gênica , Hemoglobinúria/genética , Mutação , Polimorfismo de Nucleotídeo Único , Hemoglobina Fetal/genética , Proteínas Ativadoras de GTPase/metabolismo , Hemoglobina E/genética , Hemoglobina E/metabolismo , Hemoglobinúria/sangue , Humanos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Tailândia
5.
Life Sci ; 244: 116936, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610194

RESUMO

AIMS: Long non-coding RNAs (lncRNAs) play key roles in regulating multiple cancers. TTN-AS1 was reported to function in several human malignancies. However, the biological function of TTN-AS1 in colorectal cancer (CRC) has not been explored. In this study, we aimed to investigate the role and the underlying mechanisms of TTN-AS1 in CRC progression. MAIN METHODS: RT-qPCR was used to detect the expression levels of TTN-AS1, miR-376a-3p and KLF15 in colorectal cancer tissues and cells. CCK-8, colony formation, flow cytometry and transwell assays were performed to determine the cell proliferation, apoptotic rate and invasion ability. Target genes were predicted using bioinformatics methods. si-RNA and miRNA inhibitor were transfected into CRC cells to explore the underlying mechanisms. Tumor xenografts were created to confirm the function of TTN-AS-1 in vivo. KEY FINDINGS: TTN-AS1 upregulation was observed both in CRC tissues and cell lines. Functional investigation showed that knockdown of TTN-AS1 inhibited CRC cell proliferation and invasion, while enhanced cell apoptosis. Bioinformatics analysis identified miR-376a-3p as a target of TTN-AS1. Transfection of miR-376a-3p inhibitor mitigated the alterations induced by TTN-AS1 knockdown. Moreover, TTN-AS1 positively regulated KLF15 via sponging miR-376a-3p. Additionally, these findings were supported by in vivo experiments. SIGNIFICANCE: In conclusions, TTN-AS1 promoted CRC proliferation and invasion through miR-376a-3p/KLF15 axis. Our findings suggested that TTN-AS1 might be a potential therapeutic target in CRC treatment.


Assuntos
Neoplasias Colorretais/genética , Conectina/genética , Fatores de Transcrição Kruppel-Like/metabolismo , MicroRNAs/genética , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , China , Neoplasias Colorretais/metabolismo , Conectina/metabolismo , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Fatores de Transcrição Kruppel-Like/genética , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , RNA Antissenso/genética , RNA Antissenso/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Regulação para Cima
6.
Mol Biol Evol ; 37(1): 100-109, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31504761

RESUMO

The GLIS family transcription factors, GLIS1 and GLIS3, potentiate generation of induced pluripotent stem cells (iPSCs). In contrast, another GLIS family member, GLIS2, suppresses cell reprograming. To understand how these disparate roles arose, we examined evolutionary origins and genomic organization of GLIS genes. Comprehensive phylogenetic analysis shows that GLIS1 and GLIS3 originated during vertebrate whole genome duplication, whereas GLIS2 is a sister group to the GLIS1/3 and GLI families. This result is consistent with their opposing functions in cell reprograming. Glis1 evolved faster than Glis3, losing many protein-interacting motifs. This suggests that Glis1 acquired new functions under weakened evolutionary constraints. In fact, GLIS1 induces induced pluripotent stem cells more strongly. Transcriptomic data from various animal embryos demonstrate that glis1 is maternally expressed in some tetrapods, whereas vertebrate glis3 and invertebrate glis1/3 genes are rarely expressed in oocytes, suggesting that vertebrate (or tetrapod) Glis1 acquired a new expression domain and function as a maternal factor. Furthermore, comparative genomic analysis reveals that glis1/3 is part of a bilaterian-specific gene cluster, together with rfx3, ndc1, hspb11, and lrrc42. Because known functions of these genes are related to cilia formation and function, the last common ancestor of bilaterians may have acquired this cluster by shuffling gene order to establish more sophisticated epithelial tissues involving cilia. This evolutionary study highlights the significance of GLIS1/3 for cell reprograming, development, and diseases in ciliated organs such as lung, kidney, and pancreas.


Assuntos
Evolução Molecular , Fatores de Transcrição Kruppel-Like/genética , Motivos de Aminoácidos , Animais , Reprogramação Celular , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Oócitos/metabolismo , Filogenia , Sintenia
7.
Arch Insect Biochem Physiol ; 103(3): e21609, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31385626

RESUMO

Insect metamorphosis is regulated by two main hormones: ecdysone (20E), which promotes molting, and juvenile hormone (JH), which inhibits adult morphogenesis. The transduction mechanisms for the respective hormonal signals include the transcription factors Krüppel homolog 1 (Kr-h1) and E93, which are JH- and 20E-dependent, respectively. Kr-h1 is the main effector of the antimetamorphic action of JH, while E93 is a key promoter of metamorphosis. The ancestral regulatory axis of metamorphosis, which operates in insects with hemimetabolan (gradual) metamorphosis and is known as the MEKRE93 pathway, is based on Kr-h1 repression of E93. In the last juvenile stage, when the production of JH dramatically decreases, Kr-h1 expression is almost completely interrupted, E93 becomes upregulated and metamorphosis proceeds. The holometabolan (complete) metamorphosis mode of development includes the peculiar pupal stage, a sort of intermediate between the final larval instar and the adult stage. In holometabolan species, Broad-Complex (BR-C) transcription factors determine the pupal stage and E93 stimulates the expression of BR-C in the prepupa. The MEKRE93 pathway is conserved in holometabolan insects, which have added the E93/BR-C interaction loop to the ancestral (hemimetabolan) pathway during the evolution from hemimetaboly to holometaboly.


Assuntos
Proteínas de Drosophila/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Metamorfose Biológica/fisiologia , Fatores de Transcrição/metabolismo , Animais , Proteínas de Drosophila/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição/genética
8.
Acta Biochim Biophys Sin (Shanghai) ; 52(1): 84-90, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31828306

RESUMO

KLF7, one of candidate genes in neurotherapy and metabolic syndrome, has been studied in adipogenesis of mammalian species and birds. However, the effect of the third C2H2 zinc finger of KLF7 for its transcriptional regulation in adipogenesis has not been well understood. Here, the wild-type chicken KLF7 (KLF7) overexpression plasmid, pCMV-myc-KLF7, and two plasmids of chicken KLF7 mutants, i.e. pCMV-myc-KLF7m1 with half of the third zinc finger (KLF7m1) and pCMV-myc-KLF7m2 without the third zinc finger (KLF7m2), were constructed. Luciferase reporter assay in DF1 cells showed that the effect of chicken KLF7 overexpression on the promoter activity of LPL was greater than those of KLF7m1 and KLF7m2 (P < 0.05). There was no significant difference among the overexpression of KLF7, KLF7m1 and KLF7m2 on the promoter activities of FASN, C/EBPα and FABP4 (P > 0.05). Additionally, the effects of KLF7, KLF7m1 and KLF7m2 overexpression on the promoter activity of PPARγ were different. KLF7 overexpression had no significant effect on the PPARγ promoter activity (P > 0.05), KLF7m1 overexpression suppressed PPARγ promoter activity (P < 0.05), while KLF7m2 overexpression facilitated the promoter activity of PPARγ (P < 0.05), consistent with the results of western blot analysis. Our results suggested that the third zinc finger of chicken KLF7 may play a role in its transcriptional regulation of LPL and PPARγ but has no effect on its regulation of C/EBPα, FASN and FABP4. The third zinc finger of KLF7 might be a target for the treatment of metabolic disorder in chicken.


Assuntos
Tecido Adiposo/metabolismo , Dedos de Zinco CYS2-HIS2 , Fatores de Transcrição Kruppel-Like/química , Fatores de Transcrição Kruppel-Like/genética , Transcrição Genética/genética , Adipogenia , Animais , Sítios de Ligação , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Linhagem Celular , Galinhas , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Proteínas de Ligação a Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Regulação da Expressão Gênica , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Proteínas Mutantes/genética , PPAR gama/genética , PPAR gama/metabolismo , Plasmídeos/genética , Regiões Promotoras Genéticas/genética , Análise de Sequência , Transfecção
9.
Insect Sci ; 27(2): 292-303, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30156035

RESUMO

Juvenile hormone (JH), a growth regulator, inhibits ecdysteroid-induced metamorphosis and controls insect development and diapause. Methoprene-tolerant (Met) and Krüppel homolog 1 (Kr-h1) are two proteins involved in JH action. To gain some insight into their function in development of Sitodiplosis mosellana, an insect pest undergoing obligatory larval diapause at the mature 3rd instar stage, we cloned full-length complementary DNAs of Met and Kr-h1 from this species. SmMet encoded a putative protein, which contained three domains typical of the bHLH-PAS family and eight conserved amino acid residues important for JH binding. SmKr-h1 encoded a protein showing high sequence homology to its counterparts in other species, and contained all eight highly conserved Zn-finger motifs for DNA-binding. Expression patterns of SmMet and SmKr-h1 were developmentally regulated and JH III responsive as well. Their mRNA abundance increased as larvae entered early 3rd instar, pre-diapause and maintenance stages, and peaked during post-diapause quiescence, a pattern correlated with JH titers in this species. Different from reduced expression of SmMet, SmKr-h1 mRNA increased at mid-to-late period of post-diapause development. Topical application of JH III on diapausing larvae also induced the two genes in a dose-dependent manner. Expression of SmMet and SmKr-h1 clearly declined in the pre-pupal phase, and was significantly higher in female adults than male adults. These results suggest that JH-responsive SmMet and SmKr-h1 might play key roles in diapause induction and maintenance as well as in post-diapause quiescence and adult reproduction, whereas metamorphosis from larvae to pupae might be correlated with their reduced expression.


Assuntos
Culicomorfos/genética , Proteínas de Insetos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Culicomorfos/crescimento & desenvolvimento , Culicomorfos/metabolismo , Diapausa de Inseto , Proteínas de Drosophila , Feminino , Proteínas de Insetos/metabolismo , Hormônios Juvenis/metabolismo , Fatores de Transcrição Kruppel-Like , Masculino
10.
Chem Biol Interact ; 316: 108916, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31870843

RESUMO

Oxidized low-density lipoprotein (ox-LDL)-induced endothelial inflammation plays an important role in the development of cardiovascular diseases. G protein-coupled receptors (GPCR) are gaining traction as potential treatment targets due to their roles in mediating a wide range of physiological processes. GPR120 is a recently identified omega-3 fatty acid receptor. We hypothesized that agonism of GPR120 might attenuate ox-LDL-induced endothelial dysfunction. In the present study, we tested the effects of two GPR120 agonists-GW9508 and TUG-891-in mitigating endothelial insult induced by ox-LDL in human aortic endothelial cells (HAECs). Real-time PCR, western blot, and ELISA analyses were used in our experiments. Our findings demonstrate that GPR120 is downregulated by exposure to ox-LDL, suggesting a role for GPR120 in mediating ox-LDL insult. Furthermore, we found that agonism of GPR120 could suppress oxidative stress and inflammation by inhibiting the production of reactive oxygen species and the expression of proinflammatory cytokines. Importantly, we show that agonism of GPR120 prevents the attachment of monocytes to endothelial cells by suppressing the expression of VCAM-1 and E-selectin. Finally, we show that agonism of GPR120 exerts a remarkable atheroprotective effect by elevating the expression level of Krüppel-like factor 2 (KLF2). Together, our results demonstrate a potential role for specific agonism of GPR120 in the prevention of endothelial damages induced by ox-LDL.


Assuntos
Adesão Celular/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , Metilaminas/farmacologia , Propionatos/farmacologia , Receptores Acoplados a Proteínas-G/agonistas , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Selectina E/genética , Selectina E/metabolismo , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/prevenção & controle , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Monócitos/citologia , Monócitos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
11.
Crit Rev Eukaryot Gene Expr ; 29(2): 105-112, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679265

RESUMO

OBJECTIVE: In this study, the molecular mechanism by which EPO regulates the angiogenesis after cerebral ischemia through AMPK-KLF2 signaling pathway was investigated. METHODS: Sixty healthy, male, C57BL/6 mice were randomly divided into three groups of 20 mice: a sham group, the middle cerebral artery occlusion (MCAO) group, and a MCAO+EPO treatment group. The MCAO model was established using a modified ZeaLonga method. Mice in the EPO treatment group were injected with EPO immediately after reperfusion (5000 IU/kg), and EPO was injected the following day. The number of mouse deaths and neurologic function scores were recorded during the experiment. On day 7 after cerebral ischemia, brain tissue proteins were extracted. The following proteins expressions were detected by western blot assay: EPO, vascular endothelial growth factor (VEGE), vascular endothelial growth factor receptor (KDR), adenosine activated protein kinase (AMPK), and alpha HIF-1α alpha (HIF-1α), KLF2 and nitric oxide synthase (eNOS). RESULTS: Compared with the MCAO group, the survival rate of mice in the EPO group was significantly improved and neurological function was significantly improved (P < 0.01). Western blot results showed that the content of EPO in brain tissue in MCAO group significantly increased compared with sham group. The content of EPO in the brain tissue of mice in the MCAO+EPO treatment group was significantly higher than in that of the MCAO group, which indicates that EPO increased the content of EPO in mouse brain tissue. Compared with the sham group, the protein expression of vascular endothelial growth factor (VEGE) and its receptor (KDR) in brain tissue of the MCAO group significantly decreased. However, the protein expression of VEGE and its receptor KDR in brain tissue of rats treated with MCAO+EPO was significantly higher than in that of the MCAO group. Thus, in this study, EPO was associated with vascular endothelial differentiation after cerebral ischemia in mice. The results of AMPK and KLF2 showed that the expression levels of AMPK and KLF2 in brain tissues of MCAO group mice significantly decreased compared with the sham group. However, the expression levels of AMPK and KLF2 in brain tissues of mice treated with MCAO+EPO were significantly higher than those in the MCAO group. Thus, EPO can activate AMPK and upregulate the expression of the transcription factor KLF2. The protein expression of HIF-1α in the brain tissue of mice in the MCAO group significantly increased compared with the sham group. However, the expression of HIF-1α in mice brain tissues in the MCAO+EPO treatment group was significantly lower than in that of the MCAO group, indicating that EPO was involved in regulating HIF-1α expression. The eNOS results showed that, compared with Sham group, the protein expression of eNOS in brain tissue of MCAO group mice significantly decreased. In the MCAO+EPO treatment group, the protein expression of eNOS was significantly higher in the brain tissue of the mice than in that of the MCAO group, indicating that EPO was involved in the synthesis of NO and promoted the angiogenesis. CONCLUSION: EPO promotes VEGE and its receptor (KDR) expression and participates in the regulation of HIF-1α and eNOS protein expression through the activation of AMPK-KLF2 signaling pathways to promote new vascular development after cerebral ischemia.


Assuntos
Isquemia Encefálica/fisiopatologia , Encéfalo/irrigação sanguínea , Encéfalo/efeitos dos fármacos , Eritropoetina/farmacologia , Neovascularização Patológica , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Moduladores da Angiogênese/farmacologia , Moduladores da Angiogênese/uso terapêutico , Animais , Encéfalo/fisiopatologia , Isquemia Encefálica/tratamento farmacológico , Eritropoetina/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Fatores de Transcrição Kruppel-Like/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória
12.
PLoS Genet ; 15(10): e1008443, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31661489

RESUMO

Arthropod-specific juvenile hormones control numerous essential functions in development and reproduction. In the dengue-fever mosquito Aedes aegypti, in addition to its role in immature stages, juvenile hormone III (JH) governs post-eclosion (PE) development in adult females, a phase required for competence acquisition for blood feeding and subsequent egg maturation. During PE, JH through its receptor Methoprene-tolerant (Met) regulate the expression of many genes, causing either activation or repression. Met-mediated gene repression is indirect, requiring involvement of intermediate repressors. Hairy, which functions downstream of Met in the JH gene-repression hierarchy, is one such factor. Krüppel-homolog 1, a zinc-finger transcriptional factor, is directly regulated by Met and has been implicated in both activation and repression of JH-regulated genes. However, the interaction between Hairy and Kr-h1 in the JH-repression hierarchy is not well understood. Our RNAseq-based transcriptomic analysis of the Kr-h1-depleted mosquito fat body revealed that 92% of Kr-h1 repressed genes are also repressed by Met, supporting the existence of a hierarchy between Met and Kr-h1 as previously demonstrated in various insects. Notably, 130 genes are co-repressed by both Kr-h1 and Hairy, indicating regulatory complexity of the JH-mediated PE gene repression. A mosquito Kr-h1 binding site in genes co-regulated by this factor and Hairy was identified computationally. Moreover, this was validated using electrophoretic mobility shift assays. A complete phenocopy of the effect of Met RNAi depletion on target genes could only be observed after Kr-h1 and Hairy double RNAi knockdown, suggesting a synergistic action between these two factors in target gene repression. This was confirmed using a cell-culture-based luciferase reporter assay. Taken together, our results indicate that Hairy and Kr-h1 not only function as intermediate downstream factors, but also act together in a synergistic fashion in the JH/Met gene repression hierarchy.


Assuntos
Aedes/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Insetos/metabolismo , Hormônios Juvenis/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas Repressoras/metabolismo , Aedes/crescimento & desenvolvimento , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Corpo Adiposo/metabolismo , Feminino , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Proteínas de Insetos/genética , Fatores de Transcrição Kruppel-Like/genética , Interferência de RNA , Proteínas Repressoras/genética
13.
Zhonghua Yi Xue Za Zhi ; 99(38): 3014-3018, 2019 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-31607035

RESUMO

Objective: To observe the effect of KLF3 on the expression of STAT3 in breast cancer cells, and to explore the potential mechanism of KLF3 affecting the movement, migration and invasion of breast cancer cells. Methods: Firstly, the expression of STAT3 was detected by Western blot, real-time fluorescent quantitative PCR, luciferase reporter system and chromatin immunoprecipitation in breast cancer cells. Secondly, the STAT3 promoter mutant was constructed. The plasmid further confirmed the effect of KLF3 on the activity of STAT3 promoter; the cell scratching test and Transwell method were used to detect the ability of cell movement, migration and invasion. Finally, animal experiments were conducted to verify the effect of knockdown of KLF3 on tumor metastasis in animals. Results: In breast cancer cells, knockdown of KLF3 promoted STAT3 protein expression. The mRNA level of STAT3 was increased by (3.58±0.65) fold after knockdown of KLF3 in MDA-MB-231 cells, while the mRNA level of STAT3 was increased by (2.28±0.19) fold after KLF3 knockdown in MCF-7 cells (P<0.001). KLF3 boundto the promoter region of STAT3. The transcriptional activity of STAT3 increased by (2.47±0.87) fold after knockdown of KLF3 in MDA-MB-231 cells, while the transcriptional activity of STAT3 increased by (2.63±0.65) fold after KLF3 knockdown in MCF-7 cells, P<0.01. KLF3 knockdown inhibitedthe movement,migrate and invade of breast cancer cells. Based on this, silence STAT3 partially reversed the function of KLF3. Knockdown of KLF3 promotedtumor metastasis in mice. Conclusions: KLF3 knockdown can promote the transcriptional activity of STAT3, which promotes the protein expression of the latter. KLF3 can affect the movement, migration and invasion of breast cancer cells through STAT3. KLF3 may be a potential target for the treatment of metastatic breast cancer.


Assuntos
Neoplasias da Mama , Animais , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Fatores de Transcrição Kruppel-Like , Células MCF-7 , Camundongos , Invasividade Neoplásica , Fator de Transcrição STAT3
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(5): 1463-1468, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31607299

RESUMO

OBJECTIVE: To investigate the transcriptional regulation of transcription factor MZF-1 on acute monocytic leukemia-related gene MLAA-34. METHODS: The effect of MZF-1 on the transcriptional activity of MLAA-34 gene promoter was analyzed by luciferase reporter gene detection system and site-directed mutation technique. The EMSA and ChIP assay were used to verify whether MZF-1 directly and specifically binds to the core region of MLAA-34 promoter. The over-expression vector and interference vector of MZF-1 were constructed to transfect U937 cells, and RT-PCR and Western blot were used to detect the transcription and expression changes of MLAA-34 gene. RESULTS: The transcription factor MZF-1 had a regulatory effect on MLAA-34 gene expression, and the relative luciferase activity was decreased after MZF-1 binding point mutation (P<0.01). EMSA and ChIP experiments demonstrated that MZF-1 could directly bind to MLAA-34 promoter and play a regulatory role. In the over-expression test, the increase of MZF-1 could up-regulate the expression of MLAA-34 (P<0.05). In the interference test, the decrease of MZF-1 could down-regulate the expression of MLAA-34 (P<0.05). CONCLUSION: Transcription factor MZF-1 can bind to the transcriptional regulatory region on the promoter of MLAA-34 gene and promote the transcription of MLAA-34 gene in acute monocytic leukemia.


Assuntos
Antígenos de Neoplasias/genética , Proteínas Reguladoras de Apoptose/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Leucemia Monocítica Aguda , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Fator 1-alfa Nuclear de Hepatócito , Humanos , Regiões Promotoras Genéticas , Transcrição Genética
15.
Mol Immunol ; 116: 73-79, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31630078

RESUMO

Atherosclerosis is a common comorbidity of type II diabetes and a leading cause of death worldwide. The presence of oxidized low-density lipoprotein (ox-LDL) drives atherogenesis by inducing oxidative stress, mitochondrial dysfunction, expression of proinflammatory cytokines and chemokines including interleukin (IL)-1ß, IL-6, and monocyte chemoattractant protein 1 (MCP-1), adhesion molecules including vascular cellular adhesion molecule 1 (VCAM-1) and E-selectin, and downregulating expression of the Krüppel-like factor 2 (KLF2) transcription factor. Importantly, ox-LDL induced the attachment of THP-1 monocytes to endothelial cells. In the present study, we demonstrate for the first time that the specific glucagon-like peptide 1 receptor (GLP-1R) agonist dulaglutide may prevent these atherosclerotic effects of ox-LDL by preventing suppression of KLF2 by p53 protein in human aortic endothelial cells. KLF2 has been shown to play a major role in protecting vascular endothelial cells from damage induced by ox-LDL and oscillatory shear, and therefore, therapies capable of mediating KLF2 signaling may be an attractive treatment option for preventing the development and progression of atherosclerosis.


Assuntos
Aterosclerose/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Fragmentos Fc das Imunoglobulinas/farmacologia , Lipoproteínas LDL/metabolismo , Monócitos/efeitos dos fármacos , Proteínas Recombinantes de Fusão/farmacologia , Aterosclerose/metabolismo , Adesão Celular , Células Cultivadas , Citocinas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Células Endoteliais , Regulação da Expressão Gênica/efeitos dos fármacos , Peptídeos Semelhantes ao Glucagon/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Monócitos/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Molécula 1 de Adesão de Célula Vascular/metabolismo
16.
J Biomed Sci ; 26(1): 72, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31597574

RESUMO

BACKGROUND: Transforming growth factor (TGF) family members play important roles in the regulation of corneal integrity, and the pathogenesis of corneal fibrosis. Currently, there are no effective agents targeting TGF-ß signaling to diminish corneal fibrosis. Glucosamine (GlcN), which is widely used in the treatment of osteoarthritis, abrogates the morphologic effects of TGF-ß2 on retinal pigmented epithelial cells in a mouse disease model. Here, we sought to determine whether GlcN would exert beneficial effects against TGF-ß1-induced corneal fibrosis. METHODS: In human corneal fibroblasts (HCFs) treated with GlcN, the expression of Krüppel-like factor 4 (KLF4) and its downstream signaling effects were determined in the presence and absence of TGF-ß1 using immunoblot analysis. We further explored GlcN inhibition of fibroblast-to-myofibroblast differentiation via KLF4 siRNA. The effect of cycloheximide on KLF4 protein levels with or without GlcN administration was assessed to determine whether GlcN affects the stability of the KLF4 protein. RESULTS: In HCFs, GlcN induced the expression of KLF4, which regulated the maturation and maintenance of the ocular surface. GlcN partially suppressed the TGF-ß1-induced expression of alpha-smooth muscle actin (α-SMA) and reduced the collagen contraction capacity in HCFs, suggesting a decrease in fibroblast-to-myofibroblast differentiation. This effect appeared to be mediated through suppression of Smad2 phosphorylation and ERK-dependent signaling. The levels of KLF4 mRNA were increased by GlcN and decreased by TGF-ß1 and the TGF-ß1-induced α-SMA mRNA expression was upregulated when the KLF4 gene was silenced. GlcN also appeared to stabilize the KLF4 protein, reducing its turnover in corneal fibroblasts. CONCLUSION: These findings shed light on a novel mechanism by which GlcN suppresses TGF-ß1-induced fibroblast-to-myofibroblast differentiation through the upregulation of KLF4 expression. Current strategies for treating corneal fibrosis were not effective. Elevating KLF4 levels through the use of GlcN might provide an effective alternative to alleviate the development and progression of corneal fibrosis.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Doenças da Córnea/tratamento farmacológico , Fibrose/tratamento farmacológico , Glucosamina/farmacologia , Fatores de Transcrição Kruppel-Like/genética , Fator de Crescimento Transformador beta1/genética , Doenças da Córnea/etiologia , Doenças da Córnea/genética , Cicloeximida/administração & dosagem , Fibroblastos/efeitos dos fármacos , Fibrose/etiologia , Fibrose/genética , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Miofibroblastos/fisiologia , Substâncias Protetoras/farmacologia , Inibidores da Síntese de Proteínas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo
17.
Nat Commun ; 10(1): 4596, 2019 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601799

RESUMO

Many of the regulatory features governing erythrocyte specification, maturation, and associated disorders remain enigmatic. To identify new regulators of erythropoiesis, we utilize a functional genomic screen for genes affecting expression of the erythroid marker CD235a/GYPA. Among validating hits are genes coding for the N6-methyladenosine (m6A) mRNA methyltransferase (MTase) complex, including, METTL14, METTL3, and WTAP. We demonstrate that m6A MTase activity promotes erythroid gene expression programs through selective translation of ~300 m6A marked mRNAs, including those coding for SETD histone methyltransferases, ribosomal components, and polyA RNA binding proteins. Remarkably, loss of m6A marks results in dramatic loss of H3K4me3 marks across key erythroid-specific KLF1 transcriptional targets (e.g., Heme biosynthesis genes). Further, each m6A MTase subunit and a subset of their mRNAs targets are required for human erythroid specification in primary bone-marrow derived progenitors. Thus, m6A mRNA marks promote the translation of a network of genes required for human erythropoiesis.


Assuntos
Adenosina/análogos & derivados , Eritropoese/genética , Biossíntese de Proteínas , Adenosina/genética , Antígenos CD34/genética , Antígenos CD34/metabolismo , Células da Medula Óssea/fisiologia , Sistemas CRISPR-Cas , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Regulação da Expressão Gênica , Histonas/genética , Histonas/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Leucemia Eritroblástica Aguda/genética , Metiltransferases/genética , Regiões Promotoras Genéticas , Fatores de Processamento de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulon
18.
Immunity ; 51(4): 625-637.e3, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31564469

RESUMO

Preventing aberrant immune responses against the microbiota is essential for the health of the host. Microbiota-shed pathogen-associated molecular patterns translocate from the gut lumen into systemic circulation. Here, we examined the role of hemolymph (insect blood) filtration in regulating systemic responses to microbiota-derived peptidoglycan. Drosophila deficient for the transcription factor Klf15 (Klf15NN) are viable but lack nephrocytes-cells structurally and functionally homologous to the glomerular podocytes of the kidney. We found that Klf15NN flies were more resistant to infection than wild-type (WT) counterparts but exhibited a shortened lifespan. This was associated with constitutive Toll pathway activation triggered by excess peptidoglycan circulating in Klf15NN flies. In WT flies, peptidoglycan was removed from systemic circulation by nephrocytes through endocytosis and subsequent lysosomal degradation. Thus, renal filtration of microbiota-derived peptidoglycan maintains immune homeostasis in Drosophila, a function likely conserved in mammals and potentially relevant to the chronic immune activation seen in settings of impaired blood filtration.


Assuntos
Infecções Bacterianas/imunologia , Tecido Conjuntivo/fisiologia , Drosophila/fisiologia , Glomérulos Renais/fisiologia , Fatores de Transcrição Kruppel-Like/genética , Proteínas Nucleares/genética , Podócitos/fisiologia , Animais , Animais Geneticamente Modificados , Secreções Corporais , Proteínas de Drosophila/metabolismo , Endocitose , Homeostase , Imunidade Inata , Mamíferos , Microbiota , Receptores Toll-Like/metabolismo
20.
Nat Cell Biol ; 21(10): 1179-1190, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31548608

RESUMO

Cell fate transitions are accompanied by global transcriptional, epigenetic and topological changes driven by transcription factors, as is exemplified by reprogramming somatic cells to pluripotent stem cells through the expression of OCT4, KLF4, SOX2 and cMYC. How transcription factors orchestrate the complex molecular changes around their target gene loci remains incompletely understood. Here, using KLF4 as a paradigm, we provide a transcription-factor-centric view of chromatin reorganization and its association with three-dimensional enhancer rewiring and transcriptional changes during the reprogramming of mouse embryonic fibroblasts to pluripotent stem cells. Inducible depletion of KLF factors in PSCs caused a genome-wide decrease in enhancer connectivity, whereas disruption of individual KLF4 binding sites within pluripotent-stem-cell-specific enhancers was sufficient to impair enhancer-promoter contacts and reduce the expression of associated genes. Our study provides an integrative view of the complex activities of a lineage-specifying transcription factor and offers novel insights into the nature of the molecular events that follow transcription factor binding.


Assuntos
Reprogramação Celular/genética , Montagem e Desmontagem da Cromatina/genética , Elementos Facilitadores Genéticos , Fatores de Transcrição Kruppel-Like/metabolismo , Células-Tronco Embrionárias Murinas/metabolismo , Animais , Células Cultivadas , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Células-Tronco Pluripotentes/metabolismo
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