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1.
Front Cell Dev Biol ; 11: 1120365, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36814601

RESUMO

WNT10B, a member of the WNT family of secreted glycoproteins, activates the WNT/ß-catenin signaling cascade to control proliferation, stemness, pluripotency, and cell fate decisions. WNT10B plays roles in many tissues, including bone, adipocytes, skin, hair, muscle, placenta, and the immune system. Aberrant WNT10B signaling leads to several diseases, such as osteoporosis, obesity, split-hand/foot malformation (SHFM), fibrosis, dental anomalies, and cancer. We reviewed WNT10B a decade ago, and here we provide a comprehensive update to the field. Novel research on WNT10B has expanded to many more tissues and diseases. WNT10B polymorphisms and mutations correlate with many phenotypes, including bone mineral density, obesity, pig litter size, dog elbow dysplasia, and cow body size. In addition, the field has focused on the regulation of WNT10B using upstream mediators, such as microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). We also discussed the therapeutic implications of WNT10B regulation. In summary, research conducted during 2012-2022 revealed several new, diverse functions in the role of WNT10B in physiology and disease.

2.
Int J Mol Sci ; 23(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36077068

RESUMO

Cytochrome P4501B1 (CYP1B1) is elevated in breast cancer. Studies indicate a relationship between CYP1B1 and aggressive cancer phenotypes. Here, we report on in vitro studies in triple-negative breast cancer cell lines, where knockdown (KD) of CYP1B1 was used to determine the influence of its expression on invasive cell phenotypes. CYP1B1 KD in MDA-MB-231 cells resulted in the loss of mesenchymal morphology, altered expression of epithelial-mesenchymal genes, and increased claudin (CLDN) RNA and protein. CYP1B1 KD cells had increased cell-to-cell contact and paracellular barrier function, a reduced rate of cell proliferation, abrogation of migratory and invasive activity, and diminished spheroid formation. Analysis of clinical breast cancer tumor samples revealed an association between tumors exhibiting higher CYP1B1 RNA levels and diminished overall and disease-free survival. Tumor expression of CYP1B1 was inversely associated with CLDN7 expression, and CYP1B1HI/CLDN7LOW identified patients with lower median survival. Cells with CYP1B1 KD had an enhanced chemosensitivity to paclitaxel, 5-fluorouracil, and cisplatin. Our findings that CYP1B1 KD can increase chemosensitivity points to therapeutic targeting of this enzyme. CYP1B1 inhibitors in combination with chemotherapeutic drugs may provide a novel targeted and effective approach to adjuvant or neoadjuvant therapy against certain forms of highly metastatic breast cancer.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Claudinas/genética , Citocromo P-450 CYP1B1/genética , Feminino , Humanos , Fenótipo , RNA , Neoplasias de Mama Triplo Negativas/patologia
3.
J Biol Chem ; 298(9): 102310, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35921893

RESUMO

Disruption of fetal growth results in severe consequences to human health, including increased fetal and neonatal morbidity and mortality, as well as potential lifelong health problems. Molecular mechanisms promoting fetal growth represent potential therapeutic strategies to treat and/or prevent fetal growth restriction (FGR). Here, we identify a previously unknown role for the mitogen-activated protein kinase kinase kinase 4 (MAP3K4) in promoting fetal and placental growth. We demonstrate that inactivation of MAP3K4 kinase activity causes FGR due in part to placental insufficiency. Significantly, MAP3K4 kinase-inactive mice display highly penetrant lethality prior to weaning and persistent growth reduction of surviving adults. Additionally, we elucidate molecular mechanisms by which MAP3K4 promotes growth through control of the insulin-like growth factor 1 receptor (IGF1R), insulin receptor (IR), and Akt signaling pathway. Specifically, MAP3K4 kinase inactivation in trophoblast stem (TS) cells results in reduced IGF1R and IR expression and decreased Akt activation. We observe these changes in TS cells also occur in differentiated trophoblasts created through in vitro differentiation of cultured TS cells and in vivo in placental tissues formed by TS cells. Furthermore, we show that MAP3K4 controls this pathway by promoting Igf1r transcript expression in TS cells through activation of CREB-binding protein (CBP). In the MAP3K4 kinase-inactive TS cells, Igf1r transcripts are repressed because of reduced CBP activity and increased histone deacetylase 6 expression and activity. Together, these data demonstrate a critical role for MAP3K4 in promoting fetal and placental growth by controlling the activity of the IGF1R/IR and Akt signaling pathway.


Assuntos
Desenvolvimento Fetal , MAP Quinase Quinase Quinase 4 , Placenta , Placentação , Receptor IGF Tipo 1 , Receptor de Insulina , Adulto , Animais , Proteína de Ligação a CREB/metabolismo , Feminino , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/metabolismo , Desacetilase 6 de Histona/metabolismo , Humanos , MAP Quinase Quinase Quinase 4/genética , MAP Quinase Quinase Quinase 4/metabolismo , Camundongos , Placenta/enzimologia , Gravidez , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Transdução de Sinais
4.
Biol Reprod ; 105(2): 491-502, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-33912929

RESUMO

Sex determination requires the commitment of bipotential gonads to either a testis or an ovarian fate. Gene deletion of the kinase Map3k4 results in gonadal sex reversal in XY mice, and transgenic re-expression of Map3k4 rescues the sex reversal phenotype. Map3k4 encodes a large, multi-functional protein possessing a kinase domain and several, additional protein-protein interaction domains. Although MAP3K4 plays a critical role in male gonadal sex determination, it is unknown if the kinase activity of MAP3K4 is required. Here, we use mice expressing full-length, kinase-inactive MAP3K4 from the endogenous Map3k4 locus to examine the requirement of MAP3K4 kinase activity in sex determination. Although homozygous kinase-inactivation of MAP3K4 (Map3k4KI/KI) is lethal, a small fraction survive to adulthood. We show Map3k4KI/KI adults exhibit a 4:1 female-biased sex ratio. Many adult Map3k4KI/KI phenotypic females have a Y chromosome. XY Map3k4KI/KI adults with sex reversal display female mating behavior, but do not give rise to offspring. Reproductive organs are overtly female, but there is a broad spectrum of ovarian phenotypes, including ovarian absence, primitive ovaries, reduced ovarian size, and ovaries having follicles in all stages of development. Further, XY Map3k4KI/KI adults are smaller than either male or female Map3k4WT/WT mice. Examination of the critical stage of gonadal sex determination at E11.5 shows that loss of MAP3K4 kinase activity results in the loss of Sry expression in XY Map3k4KI/KI embryos, indicating embryonic male gonadal sex reversal. Together, these findings demonstrate the essential role for kinase activity of MAP3K4 in male gonadal sex determination.


Assuntos
MAP Quinase Quinase Quinase 4/genética , Camundongos/genética , Ovário/embriologia , Processos de Determinação Sexual/genética , Testículo/embriologia , Animais , Feminino , MAP Quinase Quinase Quinase 4/metabolismo , Masculino , Camundongos/embriologia
5.
Cell Rep ; 26(13): 3684-3697.e7, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30917321

RESUMO

O-GalNAc glycosylation is initiated in the Golgi by glycosyltransferases called GALNTs. Proteomic screens identified >600 O-GalNAc-modified proteins, but the biological relevance of these modifications has been difficult to determine. We have discovered a conserved function for GALNT3 in trophoblast stem (TS) cells, blastocyst trophectoderm, and human mammary epithelial cells (HMECs). The loss of GALNT3 expression in these systems reduces O-GalNAc glycosylation and induces epithelial-mesenchymal transition. Furthermore, Galnt3 expression is reduced in aggressive, mesenchymal claudin-low breast cancer cells. We show that GALNT3 expression controls the O-GalNAc glycosylation of multiple proteins, including E-cadherin in both TS cells and HMECs. The loss of GALNT3 results in the intracellular retention of E-cadherin in the Golgi. Significantly, re-expression of GALNT3 in TS cells increases O-GalNAc glycosylation and restores the epithelial state. Together, these data demonstrate the critical biological role of GALNT3 O-GalNAc glycosylation to promote the epithelial phenotype in TS cells, blastocyst trophectoderm, and HMECs.


Assuntos
Diferenciação Celular , Células Epiteliais/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , N-Acetilgalactosaminiltransferases/metabolismo , Processamento de Proteína Pós-Traducional , Trofoblastos/citologia , Animais , Caderinas/metabolismo , Linhagem Celular Tumoral , Células Epiteliais/citologia , Transição Epitelial-Mesenquimal , Feminino , Glicosilação , Células HEK293 , Desacetilase 6 de Histona/genética , Desacetilase 6 de Histona/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Humanos , Camundongos , N-Acetilgalactosaminiltransferases/genética , Transporte Proteico , Trofoblastos/metabolismo , Polipeptídeo N-Acetilgalactosaminiltransferase
6.
J Nat Sci ; 3(9)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28936481

RESUMO

Large-scale epigenetic changes take place when epithelial cells with cell-cell adhesion and apical-basal polarity transition into invasive, individual, mesenchymal cells through a process known as epithelial to mesenchymal transition (EMT). Importantly, cancers with stem cell properties disseminate and form distant metastases by reactivating the developmental EMT program. Recent studies have demonstrated that the epigenetic histone modification, H2BK5 acetylation (H2BK5Ac), is important in the regulation of EMT. For example, in trophoblast stem (TS) cells, H2BK5Ac promotes the expression of genes important to the maintenance of an epithelial phenotype. This finding led to the discovery that TS cells and stem-like claudin-low breast cancer cells share similar H2BK5Ac-regulated gene expression, linking developmental and cancer cell EMT. An improved understanding of the role of H2BK5Ac in developmental EMT and stemness will further our understanding of epigenetics in EMT-related pathologies. Here, we examine the binders and regulators of H2BK5Ac and discuss the roles of H2BK5Ac in stemness and EMT.

7.
Cell Rep ; 18(10): 2387-2400, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28273454

RESUMO

The first epithelial-to-mesenchymal transition (EMT) occurs in trophoblast stem (TS) cells during implantation. Inactivation of the serine/threonine kinase MAP3K4 in TS cells (TSKI4 cells) induces an intermediate state of EMT, where cells retain stemness, lose epithelial markers, and gain mesenchymal characteristics. Investigation of relationships among MAP3K4 activity, stemness, and EMT in TS cells may reveal key regulators of EMT. Here, we show that MAP3K4 activity controls EMT through the ubiquitination and degradation of HDAC6. Loss of MAP3K4 activity in TSKI4 cells results in elevated HDAC6 expression and the deacetylation of cytoplasmic and nuclear targets. In the nucleus, HDAC6 deacetylates the promoters of tight junction genes, promoting the dissolution of tight junctions. Importantly, HDAC6 knockdown in TSKI4 cells restores epithelial features, including cell-cell adhesion and barrier formation. These data define a role for HDAC6 in regulating gene expression during transitions between epithelial and mesenchymal phenotypes.


Assuntos
Cromatina/metabolismo , Transição Epitelial-Mesenquimal , Desacetilase 6 de Histona/metabolismo , Células-Tronco/citologia , Trofoblastos/metabolismo , Acetilação , Animais , Diferenciação Celular , Núcleo Celular/metabolismo , Transição Epitelial-Mesenquimal/genética , MAP Quinase Quinase Quinase 4/metabolismo , Camundongos , Fenótipo , Regiões Promotoras Genéticas/genética , Ligação Proteica , Proteólise , Proteínas de Junções Íntimas/metabolismo , Ubiquitinação
8.
Curr Pathobiol Rep ; 2(1): 21-26, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25530923

RESUMO

The epithelial to mesenchymal transition (EMT) generates tumor cells having stem cell characteristics with phenotypes similar to cancer stem cells (CSCs). Evidence suggests CSCs are in an intermediate state of EMT expressing reduced levels of E-cadherin and exhibiting mesenchymal features including invasiveness associated with metastasis. These findings suggest mechanisms regulating EMT and stemness are closely integrated. Recent reports from multiple laboratories have identified novel mechanisms regulating EMT and stemness involving epigenetics, microenvironment, and dedifferentiation. Circulating tumor cells (CTCs) have also been shown to exhibit features of EMT, but it is unclear what fraction has CSCs properties. EMT characteristics of both CSCs and CTCs are associated with resistance to current clinical treatments, indicating therapies targeting the CSC in addition to the more differentiated tumor cells are required for durable responses. Thus, EMT characteristics of CTCs may prove useful biomarkers for effective therapies for many cancers.

9.
Mol Cell Biol ; 33(15): 3011-25, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23716599

RESUMO

We previously identified a gene signature predicted to regulate the epithelial-mesenchymal transition (EMT) in both epithelial tissue stem cells and breast cancer cells. A phenotypic RNA interference (RNAi) screen identified the genes within this 140-gene signature that promoted the conversion of mesenchymal epithelial cell adhesion molecule-negative (EpCAM-) breast cancer cells to an epithelial EpCAM+/high phenotype. The screen identified 10 of the 140 genes whose individual knockdown was sufficient to promote EpCAM and E-cadherin expression. Among these 10 genes, RNAi silencing of the SWI/SNF chromatin-remodeling factor Smarcd3/Baf60c in EpCAM- breast cancer cells gave the most robust transition from the mesenchymal to epithelial phenotype. Conversely, expression of Smarcd3/Baf60c in immortalized human mammary epithelial cells induced an EMT. The mesenchymal-like phenotype promoted by Smarcd3/Baf60c expression resulted in gene expression changes in human mammary epithelial cells similar to that of claudin-low triple-negative breast cancer cells. These mammary epithelial cells expressing Smarcd3/Baf60c had upregulated Wnt5a expression. Inhibition of Wnt5a by either RNAi knockdown or blocking antibody reversed Smarcd3/Baf60c-induced EMT. Thus, Smarcd3/Baf60c epigenetically regulates EMT by activating WNT signaling pathways.


Assuntos
Epigênese Genética , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Wnt/metabolismo , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proteínas Cromossômicas não Histona , Células Epiteliais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Proto-Oncogênicas/genética , Interferência de RNA , Fatores de Transcrição/genética , Regulação para Cima , Proteínas Wnt/genética , Via de Sinalização Wnt , Proteína Wnt-5a
10.
Cell ; 149(2): 307-21, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22500798

RESUMO

Kinase inhibitors have limited success in cancer treatment because tumors circumvent their action. Using a quantitative proteomics approach, we assessed kinome activity in response to MEK inhibition in triple-negative breast cancer (TNBC) cells and genetically engineered mice (GEMMs). MEK inhibition caused acute ERK activity loss, resulting in rapid c-Myc degradation that induced expression and activation of several receptor tyrosine kinases (RTKs). RNAi knockdown of ERK or c-Myc mimicked RTK induction by MEK inhibitors, and prevention of proteasomal c-Myc degradation blocked kinome reprogramming. MEK inhibitor-induced RTK stimulation overcame MEK2 inhibition, but not MEK1 inhibition, reactivating ERK and producing drug resistance. The C3Tag GEMM for TNBC similarly induced RTKs in response to MEK inhibition. The inhibitor-induced RTK profile suggested a kinase inhibitor combination therapy that produced GEMM tumor apoptosis and regression where single agents were ineffective. This approach defines mechanisms of drug resistance, allowing rational design of combination therapies for cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos , MAP Quinase Quinase 1/antagonistas & inibidores , Proteínas Quinases/genética , Proteoma/análise , Animais , Antineoplásicos/uso terapêutico , Benzenossulfonatos/uso terapêutico , Benzimidazóis/uso terapêutico , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Niacinamida/análogos & derivados , Compostos de Fenilureia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Piridinas/uso terapêutico , Receptores Proteína Tirosina Quinases/genética , Sorafenibe
12.
Cell Cycle ; 10(17): 2865-73, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21862874

RESUMO

Epithelial-mesenchymal transition (EMT) is an essential developmental program that becomes reactivated in adult tissues to promote the progression of cancer. EMT has been largely studied by examining the beginning epithelial state or the ending mesenchymal state without studying the intermediate stages. Recent studies using trophoblast stem (TS) cells paused in EMT have defined the molecular and epigenetic mechanisms responsible for modulating the intermediate "metastable" stages of EMT. Targeted inactivation of MAP3K4, knockdown of CBP, or overexpression of SNAI1 in TS cells induced similar metastable phenotypes. These TS cells exhibited epigenetic changes in the histone acetylation landscape that cause loss of epithelial maintenance while preserving self-renewal and multipotency. A similar phenotype was found in claudin-low breast cancer cells with properties of EMT and stemness. This intersection between EMT and stemness in TS cells and claudin-low metastatic breast cancer demonstrates the usefulness of developmental EMT systems to understand EMT in cancer.


Assuntos
Neoplasias da Mama/patologia , Transição Epitelial-Mesenquimal , Células-Tronco/citologia , Trofoblastos/citologia , Acetilação , Animais , Caderinas/metabolismo , Diferenciação Celular , Linhagem Celular , Polaridade Celular , Implantação do Embrião , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/patologia , Epigênese Genética , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Fator 4 de Crescimento de Fibroblastos/metabolismo , Técnicas de Silenciamento de Genes , Humanos , MAP Quinase Quinase Quinase 4/metabolismo , Camundongos , Invasividade Neoplásica , Placenta/patologia , Gravidez , Transdução de Sinais , Fatores de Transcrição da Família Snail , Células-Tronco/metabolismo , Células-Tronco/patologia , Fatores de Transcrição/metabolismo , Trofoblastos/metabolismo , Trofoblastos/patologia
13.
Nucleic Acids Res ; 39(19): e130, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21803788

RESUMO

We propose a new and effective statistical framework for identifying genome-wide differential changes in epigenetic marks with ChIP-seq data or gene expression with mRNA-seq data, and we develop a new software tool EpiCenter that can efficiently perform data analysis. The key features of our framework are: (i) providing multiple normalization methods to achieve appropriate normalization under different scenarios, (ii) using a sequence of three statistical tests to eliminate background regions and to account for different sources of variation and (iii) allowing adjustment for multiple testing to control false discovery rate (FDR) or family-wise type I error. Our software EpiCenter can perform multiple analytic tasks including: (i) identifying genome-wide epigenetic changes or differentially expressed genes, (ii) finding transcription factor binding sites and (iii) converting multiple-sample sequencing data into a single read-count data matrix. By simulation, we show that our framework achieves a low FDR consistently over a broad range of read coverage and biological variation. Through two real examples, we demonstrate the effectiveness of our framework and the usages of our tool. In particular, we show that our novel and robust 'parsimony' normalization method is superior to the widely-used 'tagRatio' method. Our software EpiCenter is freely available to the public.


Assuntos
Epigênese Genética , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Animais , Sítios de Ligação , Interpretação Estatística de Dados , Genômica/métodos , Histonas/metabolismo , Masculino , Software , Fatores de Transcrição/metabolismo , Inativação do Cromossomo X
14.
Cell Stem Cell ; 8(5): 525-37, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21549327

RESUMO

Epithelial stem cells self-renew while maintaining multipotency, but the dependence of stem cell properties on maintenance of the epithelial phenotype is unclear. We previously showed that trophoblast stem (TS) cells lacking the protein kinase MAP3K4 maintain properties of both stemness and epithelial-mesenchymal transition (EMT). Here, we show that MAP3K4 controls the activity of the histone acetyltransferase CBP, and that acetylation of histones H2A and H2B by CBP is required to maintain the epithelial phenotype. Combined loss of MAP3K4/CBP activity represses expression of epithelial genes and causes TS cells to undergo EMT while maintaining their self-renewal and multipotency properties. The expression profile of MAP3K4-deficient TS cells defines an H2B acetylation-regulated gene signature that closely overlaps with that of human breast cancer cells. Taken together, our data define an epigenetic switch that maintains the epithelial phenotype in TS cells and reveals previously unrecognized genes potentially contributing to breast cancer.


Assuntos
Células-Tronco Embrionárias/metabolismo , Transição Epitelial-Mesenquimal , Histonas/metabolismo , Proteínas de Membrana/metabolismo , Células-Tronco Multipotentes/metabolismo , Fosfoproteínas/metabolismo , Acetilação , Animais , Linhagem Celular , Sobrevivência Celular/genética , Transformação Celular Neoplásica/genética , Células-Tronco Embrionárias/patologia , Epigênese Genética , Transição Epitelial-Mesenquimal/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Histonas/genética , MAP Quinase Quinase Quinase 4/genética , MAP Quinase Quinase Quinase 4/metabolismo , Camundongos , Células-Tronco Multipotentes/patologia , Mutação/genética , Trofoblastos/patologia
15.
J Biol Chem ; 285(16): 11760-4, 2010 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-20181950

RESUMO

Cerebral cavernous malformations (CCM) are vascular lesions causing seizures and stroke. Mutations causing inactivation of one of three genes, ccm1, -2, or -3, are sufficient to induce vascular endothelial cell defects resulting in CCM. Herein, we show that loss of expression of the CCM1, -2, or -3 proteins causes a marked increase in expression of the GTPase RhoA. Live cell imaging with a RhoA-specific biosensor demonstrates increased RhoA activity with loss of CCM1, -2, or -3, with an especially pronounced RhoA activation in both the cytosol and the nucleus with loss of CCM1 expression. Increased RhoA activation was associated with Rho kinase-dependent phosphorylation of myosin light chain 2. Functionally, loss of CCM1, -2, or -3 inhibited endothelial cell vessel-like tube formation and extracellular matrix invasion, each of which is rescued by chemical inhibition or short hairpin RNA knockdown of Rho kinase. The findings, for the first time, define a signaling network for CCM1, -2, and -3 in CCM pathology, whereby loss of CCM1, -2, or -3 protein expression results in increased RhoA activity, with the activation of Rho kinase responsible for endothelial cell dysregulation. The results define Rho kinase as a therapeutic target to rescue endothelial cells from loss of CCM protein function.


Assuntos
Hemangioma Cavernoso do Sistema Nervoso Central/genética , Hemangioma Cavernoso do Sistema Nervoso Central/metabolismo , Quinases Associadas a rho/antagonistas & inibidores , Amidas/farmacologia , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Técnicas Biossensoriais , Miosinas Cardíacas/metabolismo , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/genética , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Hemangioma Cavernoso do Sistema Nervoso Central/tratamento farmacológico , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Humanos , Proteína KRIT1 , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Proteínas Associadas aos Microtúbulos/genética , Cadeias Leves de Miosina/metabolismo , Fenótipo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Piridinas/farmacologia , Interferência de RNA , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
16.
Mol Cell Biol ; 29(10): 2748-61, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19289495

RESUMO

Trophoblast differentiation during placentation involves an epithelial-mesenchymal transition (EMT) with loss of E-cadherin and gain of trophoblast invasiveness. Mice harboring a point mutation that renders inactive the mitogen-activated protein kinase kinase kinase MEKK4 exhibit dysregulated placental development with increased trophoblast invasion. Isolated MEKK4 kinase-inactive trophoblast stem (TS) cells cultured under undifferentiating, self-renewing conditions in the presence of fibroblast growth factor 4 (FGF4) display increased expression of Slug, Twist, and matrix metalloproteinase 2 (MMP2), loss of E-cadherin, and hyperinvasion of extracellular matrix, each a hallmark of EMT. MEKK4 kinase-inactive TS cells show a preferential differentiation to Tpbp alpha- and Gcm1-positive trophoblasts, which are indicative of spongiotrophoblast and syncytiotrophoblast differentiation, respectively. FGF4-stimulated Jun N-terminal kinase (JNK) and p38 activity is markedly reduced in MEKK4 kinase-inactive TS cells. Chemical inhibition of JNK in wild-type TS cells induced a similar EMT response as loss of MEKK4 kinase activity, including inhibition of E-cadherin expression and increased expression of Slug, MMP2, Tpbp alpha, and Gcm1. Chromatin immunoprecipitation analyses revealed changes in AP-1 composition with increased Fra-2 and decreased Fra-1 and JunB binding to the regulatory regions of Gcm1 and MMP2 genes in MEKK4 kinase-inactive TS cells. Our results define MEKK4 as a signaling hub for FGF4 activation of JNK that is required for maintenance of TS cells in an undifferentiated state.


Assuntos
Embrião de Mamíferos , Fator 4 de Crescimento de Fibroblastos/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , MAP Quinase Quinase Quinase 4/metabolismo , Células-Tronco/fisiologia , Trofoblastos/citologia , Ativinas/genética , Ativinas/metabolismo , Animais , Caderinas/metabolismo , Catepsinas/genética , Catepsinas/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Proteínas de Ligação a DNA , Embrião de Mamíferos/citologia , Embrião de Mamíferos/fisiologia , Ativação Enzimática , Matriz Extracelular , Feminino , Fator 4 de Crescimento de Fibroblastos/genética , Proteínas Quinases JNK Ativadas por Mitógeno/genética , MAP Quinase Quinase Quinase 4/genética , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Placenta/citologia , Gravidez , Transdução de Sinais/fisiologia , Fatores de Transcrição da Família Snail , Células-Tronco/citologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Trofoblastos/fisiologia , Proteína 1 Relacionada a Twist/genética , Proteína 1 Relacionada a Twist/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
J Biol Chem ; 282(42): 30476-84, 2007 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-17726008

RESUMO

The MAPK kinase kinase MEKK4 is required for neurulation and skeletal patterning during mouse development. MEKK4 phosphorylates and activates MKK4/MKK7 and MKK3/MKK6 leading to the activation of JNK and p38, respectively. MEKK4 is believed to be auto-inhibited, and its interaction with other proteins controls its dimerization and activation. TRAF4, GADD45, and Axin each bind and activate MEKK4, with TRAF4 and Axin binding to the kinase domain and GADD45 binding within the N-terminal regulatory domain. Here we show that similar to the interaction with TRAF4 and Axin, the kinase domain of MEKK4 interacts with the multifunctional serine/threonine kinase GSK3beta. GSK3beta binding to MEKK4 blocks MEKK4 dimerization that is required for MEKK4 activation, effectively inhibiting MEKK4 stimulation of the JNK and p38 MAPK pathways. Inhibition of GSK3beta kinase activity with SB216763 results in enhanced MEKK4 kinase activity and increased JNK and p38 activation, indicating that an active state of GSK3beta is required for binding and inhibition of MEKK4 dimerization. Furthermore, GSK3beta phosphorylates specific serines and threonines in the N terminus of MEKK4. Together, these findings demonstrate that GSK3beta binds to the kinase domain of MEKK4 and regulates MEKK4 dimerization. However, unlike TRAF4, Axin, and GADD45, GSK3beta inhibits MEKK4 activity and prevents its activation of JNK and p38. Thus, control of MEKK4 dimerization is regulated both positively and negatively by its interaction with specific proteins.


Assuntos
Quinase 3 da Glicogênio Sintase/metabolismo , MAP Quinase Quinase 4/metabolismo , MAP Quinase Quinase Quinase 4/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Proteína Axina , Células COS , Proteínas de Ciclo Celular/metabolismo , Chlorocebus aethiops , Dimerização , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta , Indóis/farmacologia , MAP Quinase Quinase 3/metabolismo , MAP Quinase Quinase 4/antagonistas & inibidores , MAP Quinase Quinase 6/metabolismo , MAP Quinase Quinase 7/metabolismo , MAP Quinase Quinase Quinase 4/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Maleimidas/farmacologia , Camundongos , Proteínas Nucleares/metabolismo , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Estrutura Terciária de Proteína/fisiologia , Proteínas Repressoras/metabolismo , Fator 4 Associado a Receptor de TNF/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
18.
Mol Cell Biol ; 25(20): 8948-59, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16199873

RESUMO

Skeletal disorders and neural tube closure defects represent clinically significant human malformations. The signaling networks regulating normal skeletal patterning and neurulation are largely unknown. Targeted mutation of the active site lysine of MEK kinase 4 (MEKK4) produces a kinase-inactive MEKK4 protein (MEKK4(K1361R)). Embryos homozygous for this mutation die at birth as a result of skeletal malformations and neural tube defects. Hindbrains of exencephalic MEKK4(K1361R) embryos show a striking increase in neuroepithelial cell apoptosis and a dramatic loss of phosphorylation of MKK3 and -6, mitogen-activated protein kinase kinases (MKKs) regulated by MEKK4 in the p38 pathway. Phosphorylation of MAPK-activated protein kinase 2, a p38 substrate, is also inhibited, demonstrating a loss of p38 activity in MEKK4(K1361R) embryos. In contrast, the MEK1/2-extracellular signal-regulated kinase 1 (ERK1)/ERK2 and MKK4-Jun N-terminal protein kinase pathways were unaffected. The p38 pathway has been shown to regulate the phosphorylation and expression of the small heat shock protein HSP27. Compared to the wild type, MEKK4(K1361R) fibroblasts showed significantly reduced phosphorylation of p38 and HSP27, with a corresponding heat shock-induced instability of the actin cytoskeleton. Together, these data demonstrate MEKK4 regulation of p38 and that substrates downstream of p38 control cellular homeostasis. The findings are the first demonstration that MEKK4-regulated p38 activity is critical for neurulation.


Assuntos
Desenvolvimento Ósseo/fisiologia , MAP Quinase Quinase Quinase 4/deficiência , Defeitos do Tubo Neural/enzimologia , Animais , Apoptose , Sequência de Bases , Padronização Corporal/genética , Padronização Corporal/fisiologia , Desenvolvimento Ósseo/genética , DNA/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Marcação de Genes , Humanos , MAP Quinase Quinase Quinase 4/genética , MAP Quinase Quinase Quinase 4/fisiologia , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Defeitos do Tubo Neural/embriologia , Defeitos do Tubo Neural/genética , Defeitos do Tubo Neural/patologia , Fenótipo , Fosforilação , Gravidez , Rombencéfalo/anormalidades , Rombencéfalo/enzimologia , Rombencéfalo/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
19.
J Biol Chem ; 280(43): 35793-6, 2005 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-16157600

RESUMO

TRAF4 has previously been shown to activate JNK through an unknown mechanism. Here, we show that endogenous TRAF4 and MEKK4 associate in both human K562 cells and mouse E10.5 embryos. TRAF4 interacts with the kinase domain of MEKK4. However, this association does not require MEKK4 kinase activity. The interaction of MEKK4 and TRAF4 are further demonstrated by the colocalization of TRAF4 and MEKK4 in cells. Importantly, although TRAF4 has little or no ability to activate JNK independently, coexpression of TRAF4 and MEKK4 results in synergistic activation of JNK that is inhibited by a kinase-inactive mutant of MEKK4, MEKK4K1361R. MEKK4 binds the TRAF domain of TRAF4 and MEKK4/TRAF4 activation of JNK is inhibited by expression of the TRAF domain. Furthermore, TRAF4 stimulates MEKK4 kinase activity by promoting MEKK4 oligomerization and JNK activation can be stimulated by chemical induction of MEKK4 dimerization. The findings identify MEKK4 as the MAPK kinase kinase for TRAF4 regulation of the JNK pathway.


Assuntos
MAP Quinase Quinase Quinase 4/fisiologia , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/fisiologia , Animais , Western Blotting , Células COS , Linhagem Celular , Células Cultivadas , Chlorocebus aethiops , Citoplasma/metabolismo , DNA Complementar/metabolismo , Dimerização , Ativação Enzimática , Vetores Genéticos , Humanos , Imunoprecipitação , Células K562 , MAP Quinase Quinase 4/metabolismo , MAP Quinase Quinase Quinase 4/metabolismo , Camundongos , Microscopia de Fluorescência , Mutação , Fosforilação , Ligação Proteica , Estrutura Terciária de Proteína , Transdução de Sinais , Fator 4 Associado a Receptor de TNF , Transfecção
20.
Hum Mol Genet ; 14(17): 2521-31, 2005 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16037064

RESUMO

Cerebral cavernous malformations (CCMs) are sporadically acquired or inherited vascular lesions of the central nervous system consisting of clusters of dilated thin-walled blood vessels that predispose individuals to seizures and stroke. Familial CCM is caused by mutations in KRIT1 (CCM1) or in malcavernin (CCM2), the murine ortholog of which was concurrently characterized as osmosensing scaffold for MEKK3 (OSM). The roles of the CCM proteins in the pathogenesis of the disorder remain largely unknown. Here, we use co-immunoprecipitation, fluorescence resonance energy transfer and subcellular localization strategies to show that the CCM1 gene product, KRIT1, interacts with the CCM2 gene product, malcavernin/OSM. Analogous to the established interactions of CCM1 and beta1 integrin with ICAP1, the CCM1/CCM2 association is dependent upon the phosphotyrosine binding (PTB) domain of CCM2. A familial CCM2 missense mutation abrogates the CCM1/CCM2 interaction, suggesting that loss of this interaction may be critical in CCM pathogenesis. CCM2 and ICAP1 bound to CCM1 via their respective PTB domains differentially influence the subcellular localization of CCM1. Furthermore, we expand upon the established involvement of CCM2 in the p38 mitogen-activated protein kinase signaling module by demonstrating that CCM1 associates with CCM2 and MEKK3 in a ternary complex. These data indicate that the genetic heterogeneity observed in familial CCM may reflect mutation of different molecular members of a coordinated signaling complex.


Assuntos
Encéfalo/anormalidades , Proteínas de Transporte/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Substituição de Aminoácidos , Animais , Linhagem Celular , Modelos Animais de Doenças , Fibroblastos/fisiologia , Mutação em Linhagem Germinativa , Heterozigoto , Humanos , Proteína KRIT1 , Camundongos , Mutagênese Sítio-Dirigida
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