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1.
Proc Natl Acad Sci U S A ; 121(5): e2318718121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38252820

RESUMO

Several compounds have been used for atherosclerosis treatment, including clinical trials; however, no anti-atherosclerotic drugs based on hemodynamic force-mediated atherogenesis have been discovered. Our previous studies demonstrated that "small mothers against decapentaplegic homolog 1/5" (Smad1/5) is a convergent signaling molecule for chemical [e.g., bone morphogenetic proteins (BMPs)] and mechanical (e.g., disturbed flow) stimulations and hence may serve as a promising hemodynamic-based target for anti-atherosclerosis drug development. The goal of this study was to develop a high-throughput screening (HTS) platform to identify potential compounds that can inhibit disturbed flow- and BMP-induced Smad1/5 activation and atherosclerosis. Through HTS using a Smad1/5 downstream target inhibitor of DNA binding 1 (Id-1) as a luciferase reporter, we demonstrated that KU-55933 and Apicidin suppressed Id-1 expression in AD-293 cells. KU-55933 (10 µM), Apicidin (10 µM), and the combination of half doses of each [1/2(K + A)] inhibited disturbed flow- and BMP4-induced Smad1/5 activation in human vascular endothelial cells (ECs). KU-55933, Apicidin, and 1/2(K + A) treatments caused 50.6%, 47.4%, and 73.3% inhibitions of EC proliferation induced by disturbed flow, respectively, whereas EC inflammation was only suppressed by KU-55933 and 1/2(K + A), but not Apicidin alone. Administrations of KU-55933 and 1/2(K + A) to apolipoprotein E-deficient mice inhibited Smad1/5 activation in ECs in athero-susceptible regions, thereby suppressing endothelial proliferation and inflammation, with the attenuation of atherosclerotic lesions in these mice. A unique drug screening platform has been developed to demonstrate that KU-55933 and its combination with Apicidin are promising therapeutic compounds for atherosclerosis based on hemodynamic considerations.


Assuntos
Aterosclerose , Células Endoteliais , Morfolinas , Pironas , Humanos , Animais , Camundongos , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala , Aterosclerose/tratamento farmacológico , Hemodinâmica , Inflamação
2.
Eur Heart J ; 44(4): 304-318, 2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36380599

RESUMO

BACKGROUND AND AIMS: Atherosclerosis preferentially develops in arterial branches and curvatures where vascular endothelium is exposed to disturbed flow. In this study, the effects of disturbed flow on the regulation of vascular endothelial phosphoproteins and their contribution to therapeutic application in atherogenesis were elucidated. METHODS: Porcine models, large-scale phosphoproteomics, transgenic mice, and clinical specimens were used to discover novel site-specific phosphorylation alterations induced by disturbed flow in endothelial cells (ECs). RESULTS: A large-scale phosphoproteomics analysis of native endothelium from disturbed (athero-susceptible) vs. pulsatile flow (athero-resistant) regions of porcine aortas led to the identification of a novel atherosclerosis-related phosphoprotein vinculin (VCL) with disturbed flow-induced phosphorylation at serine 721 (VCLS721p). The induction of VCLS721p was mediated by G-protein-coupled receptor kinase 2 (GRK2)S29p and resulted in an inactive form of VCL with a closed conformation, leading to the VE-cadherin/catenin complex disruption to enhance endothelial permeability and atherogenesis. The generation of novel apolipoprotein E-deficient (ApoE-/-) mice overexpressing S721-non-phosphorylatable VCL mutant in ECs confirmed the critical role of VCLS721p in promoting atherosclerosis. The administration of a GRK2 inhibitor to ApoE-/- mice suppressed plaque formation by inhibiting endothelial VCLS721p. Studies on clinical specimens from patients with coronary artery disease (CAD) revealed that endothelial VCLS721p is a critical clinicopathological biomarker for atherosclerosis progression and that serum VCLS721p level is a promising biomarker for CAD diagnosis. CONCLUSIONS: The findings of this study indicate that endothelial VCLS721p is a valuable hemodynamic-based target for clinical assessment and treatment of vascular disorders resulting from atherosclerosis.


Assuntos
Aterosclerose , Células Endoteliais , Vinculina , Animais , Camundongos , Aterosclerose/patologia , Células Endoteliais/patologia , Endotélio Vascular/patologia , Camundongos Knockout para ApoE , Fosforilação , Suínos , Humanos
3.
Circ Res ; 129(12): 1158-1174, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34747636

RESUMO

RATIONALE: Disturbed flow occurring in arterial branches and curvatures induces vascular endothelial cell (EC) dysfunction and atherosclerosis. We postulated that disturbed flow plays important role in modulating phosphoprotein expression profiles to regulate endothelial functions and atherogenesis. OBJECTIVE: The goal of this study is to discover novel site-specific phosphorylation alterations induced by disturbed flow in ECs to contribute to atherosclerosis. METHODS AND RESULTS: Quantitative phosphoproteomics analysis of ECs exposed to disturbed flow with low and oscillatory shear stress (0.5±4 dynes/cm2) versus pulsatile shear stress (12±4 dynes/cm2) revealed that oscillatory shear stress induces phospho-YY1S118 (serine [S]118 phosphorylation of Yin Yang 1) in ECs. Elevated phospho-YY1S118 level in ECs was further confirmed to be present in the disturbed flow regions in experimental animals and human atherosclerotic arteries. This disturbed flow-induced EC phospho-YY1S118 is mediated by CK2α (casein kinase 2α) through its direct interaction with YY1. Yeast 2-hybrid library screening and in situ proximity ligation assays demonstrate that phospho-YY1S118 directly binds ZKSCAN4 (zinc finger with KRAB [krüppel-associated box] and SCAN [SRE-ZBP, CTfin51, AW-1 and Number 18 cDNA] domains 4) to induce promoter activity and gene expression of HDM2 (human double minute 2), which consequently induces EC proliferation through downregulation of p53 and p21CIP1. Administration of apoE-deficient (ApoE-/-) mice with CK2-specific inhibitor tetrabromocinnamic acid or atorvastatin inhibits atherosclerosis formation through downregulations of EC phospho-YY1S118 and HDM2. Generation of novel transgenic mice bearing EC-specific overexpression of S118-nonphosphorylatable mutant of YY1 in ApoE-/- mice confirms the critical role of phospho-YY1S118 in promoting atherosclerosis through EC HDM2. CONCLUSIONS: Our findings provide new insights into the mechanisms by which disturbed flow induces endothelial phospho-YY1S118 to promote atherosclerosis, thus indicating phospho-YY1S118 as a potential molecular target for atherosclerosis treatment.


Assuntos
Aterosclerose/metabolismo , Células Endoteliais/metabolismo , Fator de Transcrição YY1/metabolismo , Animais , Aterosclerose/fisiopatologia , Sítios de Ligação , Circulação Sanguínea , Caseína Quinase II/metabolismo , Linhagem Celular , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Ligação Proteica , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Transcrição YY1/química , Fator de Transcrição YY1/genética , Dedos de Zinco
4.
Phys Rev Lett ; 128(20): 202302, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35657879

RESUMO

With the tremendous accomplishments of RHIC and the LHC experiments and the advent of the future electron-ion collider on the horizon, the quest for compelling evidence of the color glass condensate (CGC) has become one of the most aspiring goals in the high energy quantum chromodynamics research. Pursuing this question requires developing the precision test of the CGC formalism. By systematically implementing the threshold resummation, we significantly improve the stability of the next-to-leading-order calculation in CGC for forward rapidity hadron productions in pp and pA collisions, especially in the high p_{T} region, and obtain reliable descriptions of all existing data measured at RHIC and the LHC across all p_{T} regions. Consequently, this technique can pave the way for the precision studies of the CGC next-to-leading-order predictions by confronting them with a large amount of precise data.

5.
J Craniofac Surg ; 33(1): 183-186, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34320576

RESUMO

BACKGROUND: According to Tessier classification, number 1 and number 2 craniofacial clefts involve the nasal ala. Congenital nasal cleft is not common and is difficult for reconstruction. Notches in the medial one-third of either nasal ala are typical manifestations in these patients. Herein, we introduce a alar rim triangular flap, which is indeed a local flap, for the treatment of isolated nasal cleft due to congenital deformities in pediatric patients. METHODS: The authors conducted a retrospective cohort study including 10 consecutive pediatric patients undergoing this surgery. This alar rim triangular flap including 2 triangles was existing nasal tissue near the cleft. The alar rim defect was covered through local tissue re-arrangement. The authors reviewed the photographs and clinical medical notes of these patients carefully. Self-reported satisfactions of patients (or children's parents) with the scar morphology and correction effect of this procedure were evaluated as well at postoperative every follow-up. RESULTS: All the cases were followed up regularly, and the average follow-up time was 22 months (ranged from 13-38 months). All the nasal clefts were reconstructed successfully. The alar rim triangular flap survived with no flap loss. The wound created by this procedure healed primarily. No alar retraction, nasal obstruction or step-off deformities were observed during postoperative follow-up. There were no patients unsatisfied with the outcome of the scar morphology and correction effect of this operation. CONCLUSIONS: The newly designed alar rim triangular flap in this study can be an alternative treatment for correcting isolated congenital nasal cleft with optimal clinical outcome. LEVEL OF EVIDENCE: Level 4.


Assuntos
Fenda Labial , Obstrução Nasal , Rinoplastia , Criança , Fenda Labial/cirurgia , Humanos , Nariz/cirurgia , Estudos Retrospectivos , Retalhos Cirúrgicos , Resultado do Tratamento
6.
Phys Rev Lett ; 122(17): 172302, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31107089

RESUMO

Using the dilute-dense factorization in the color glass condensate framework, we investigate the azimuthal angular correlation between a heavy quarkonium and a charged light hadron in proton-nucleus collisions. We extract the second harmonic v_{2}, commonly known as the elliptic flow, with the light hadron as the reference. This particular azimuthal angular correlation between a heavy meson and a light hadron was first measured at the LHC recently. The experimental results indicate that the elliptic flows for heavy flavor mesons (J/ψ and D^{0}) are almost as large as those for light hadrons. Our calculation demonstrates that this result can be naturally interpreted as an initial state effect due to the interaction between the incoming partons from the proton and the dense gluons inside the target nucleus. Since the heavy quarkonium v_{2} exhibits a weak mass dependence according to our calculation, we predict that the heavy quarkonium ϒ should have a similar elliptic flow as compared to that of the J/ψ, which can be tested in future measurements.

7.
J Biomed Sci ; 25(1): 1, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-29295709

RESUMO

BACKGROUND: Atherosclerosis occurs in arterial curvatures and branches, where the flow is disturbed with low and oscillatory shear stress (OSS). The remodeling and alterations of extracellular matrices (ECMs) and their composition is the critical step in atherogenesis. In this study, we investigated the effects of different ECM proteins on the regulation of mechanotransduction in vascular endothelial cells (ECs) in response to OSS. METHODS: Through the experiments ranging from in vitro cell culture studies on effects of OSS on molecular signaling to in vivo examinations on clinical specimens from patients with coronary artery disease (CAD), we elucidated the roles of integrins and different ECMs, i.e., fibronectin (FN) and laminin (LM), in transforming growth factor (TGF)-ß receptor (TßR)-mediated Smad2 activation and nuclear factor-κB (NF-κB) signaling in ECs in response to OSS and hence atherogenesis. RESULTS: OSS at 0.5±12 dynes/cm2 induces sustained increases in the association of types I and II TßRs with ß1 and ß3 integrins in ECs grown on FN, but it only transient increases in ECs grown on LM. OSS induces a sustained activation of Smad2 in ECs on FN, but only a transient activation of Smad2 in ECs on LM. OSS-activation of Smad2 in ECs on FN regulates downstream NF-κB signaling and pro-inflammatory gene expression through the activation of ß1 integrin and its association with TßRs. In contrast, OSS induces transient activations of ß1 and ß3 integrins in ECs on LM, which associate with type I TßR to regulate Smad2 phosphorylation, resulting in transient induction of NF-κB and pro-inflammatory gene expression. In vivo investigations on diseased human coronary arteries from CAD patients revealed that Smad2 is highly activated in ECs of atherosclerotic lesions, which is accompanied by the concomitant increase of FN rather than LM in the EC layer and neointimal region of atherosclerotic lesions. CONCLUSIONS: Our findings provide new insights into the mechanisms of how OSS regulates Smad2 signaling and pro-inflammatory genes through the complex signaling networks of integrins, TßRs, and ECMs, thus illustrating the molecular basis of regional pro-inflammatory activation within disturbed flow regions in the arterial tree.


Assuntos
Células Endoteliais/fisiologia , Mecanotransdução Celular , Proteína Smad2/genética , Fenômenos Biomecânicos , Células Cultivadas , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Fibronectinas/genética , Fibronectinas/metabolismo , Humanos , Laminina/genética , Laminina/metabolismo , Proteína Smad2/metabolismo , Estresse Mecânico
8.
Aesthetic Plast Surg ; 42(1): 188-196, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29026957

RESUMO

BACKGROUND: The inverted peno-scrotal flap method is considered the standard method of vaginoplasty in male-to-female genital reassignment surgery. Though with numerous advantages, the method has its limitations regarding skin texture, lack of inherent lubrication, and that the tissues for creating the labia depend on the amount of tissues remaining after vaginoplasty. Our purpose was to describe the procedure and outcome of vaginoplasty applying a new technique: autologous buccal micro-mucosa free graft combined with posterior scrotal flap transfer, which could solve some of the problems the previous methods had. METHODS: Nine male-to-female transsexual patients received our new method of vaginoplasty from July 2010-October 2015. We described the details of the surgical procedure and evaluated the long-term anatomical and functional outcomes. RESULTS: In a mean clinical follow-up period of 25.3 months and phone interview follow-up of 50.3 months, we observed that the neovaginas in the nine cases were all of sufficient volume, lined with mucosa, with natural mucosal discharge. The oral donor sites resulted in no visible scars or malfunction. Eight patients experienced uneventful postoperative periods, while one patient suffered from scrotal flap prolapse. All the patients were sexually active and reported sexual satisfaction, with no need of lubrication. CONCLUSION: The reported technique achieves the outcomes of creating a neovagina of sufficient volume, without serious stenosis in long-term follow-up. The neovagina is lined with mucosa and has appropriate lubrication as well as good sexual sensation. The reported method is easy and economical to perform and retains enough tissues for vulvoplasty to achieve a superior cosmetic appearance, with rare risk of complications and donor area malfunction. Additionally, this technique is feasible and advantageous to the patients who have insufficient peno-scrotal skin for neovaginal lining as well as those with unfavorable previous vaginoplasty. All of these indicate that this technique is a promising option for vaginoplasty in male-to-female transsexual surgery. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Retalhos de Tecido Biológico/transplante , Mucosa Bucal/transplante , Escroto/cirurgia , Cirurgia de Readequação Sexual/métodos , Transexualidade/cirurgia , Vagina/cirurgia , Adulto , Autoenxertos , Terapia Combinada , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação Pessoal , Projetos Piloto , Prognóstico , Qualidade de Vida , Medição de Risco , Escroto/transplante , Resultado do Tratamento , Adulto Jovem
9.
J Biol Chem ; 289(27): 19120-36, 2014 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-24831011

RESUMO

In Trichomonas vaginalis, a Myb1 protein was previously demonstrated to repress transcription of an iron-inducible ap65-1 gene. In this study, a human cyclophilin A homologue, TvCyclophilin 1 (TvCyP1), was identified as a Myb1-binding protein using a bacterial two-hybrid library screening system. The recombinant TvCyP1 exhibited typical peptidyl-prolyl isomerase activity with kcat/Km of ∼7.1 µm(-1) s(-1). In a pulldown assay, the His-tagged Myb1 interacted with a GST-TvCyP1 fusion protein, which had an enzymatic proficiency half that of recombinant TvCyP1. Both the enzymatic proficiency of GST-TvCyP1 and its binding to His-Myb1 were eliminated by mutation of Arg(63) in the catalytic motif or inhibited by cyclosporin A. TvCyP1 was primarily localized to the hydrogenosomes by immunofluorescence assay, but it was also co-purified with Myb1 in certain vesicle fractions from differential and gradient centrifugations. Transgenic cells overexpressing HA-TvCyP1 had a higher level of nuclear Myb1 but a much lower level of Myb1 associated with the vesicles than control and those overexpressing HA-TvCyP1(R63A). Myb1 was detected at a much higher level in the HA-TvCyP1 protein complex than in the HA-TvCyP1(R63A) protein complex immunoprecipitated from P15 and P100, but not S100, fractions of postnuclear lysates. A TvCyP1-binding motif, (105)YGPKWNK(111), was identified in Myb1 in which Gly(106) and Pro(107) were essential for its binding to TvCyP1. Mutation of Gly(106) and Pro(107), respectively, in HA-Myb1 resulted in cytoplasmic retention and elevated nuclear translocation of the overexpressed protein. These results suggest that TvCyP1 may induce the release of Myb1 that is restrained to certain cytoplasmic vesicles prior to its nuclear translocation.


Assuntos
Núcleo Celular/metabolismo , Proteínas de Protozoários/metabolismo , Fatores de Transcrição/metabolismo , Trichomonas vaginalis/citologia , Trichomonas vaginalis/metabolismo , Transporte Ativo do Núcleo Celular , Sequência de Aminoácidos , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas de Protozoários/química , Fatores de Transcrição/química
10.
Proc Natl Acad Sci U S A ; 109(20): 7770-5, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22550179

RESUMO

Vascular endothelial cells (ECs) are constantly exposed to blood flow-induced shear stress, but the mechanism of force-specific activation of their signaling to modulate cellular function remains unclear. We have demonstrated that bone morphogenetic protein receptor (BMPR)-specific Smad1/5 can be force-specifically activated by oscillatory shear stress (OSS) in ECs to cause cell cycle progression. Smad1/5 is highly activated in ECs of atherosclerotic lesions in diseased human coronary arteries from patients with end-stage heart failure undergoing heart transplantation and from apolipoprotein E-deficient mice. Application of OSS (0.5 ± 4 dyn/cm(2)) causes the sustained activation of Smad1/5 in ECs through activations of mammalian target of rapamycin and p70S6 kinase, leading to up-regulation of cyclin A and down-regulations of p21(CIP1) and p27(KIP1) and, hence, EC cycle progression. En face examination of rat aortas reveals high levels of phospho-Smad1/5 in ECs of the inner, but not the outer, curvature of aortic arch, nor the straight segment of thoracic aorta [corrected]. Immunohistochemical and en face examinations of the experimentally stenosed abdominal aorta in rats show high levels of phospho-Smad1/5 in ECs at poststenotic sites, where OSS occurs. These OSS activations of EC Smad1/5 in vitro and in vivo are not inhibited by the BMP-specific antagonist Noggin and, hence, are independent of BMP ligand. Transfecting ECs with Smad1/5-specific small interfering RNAs inhibits the OSS-induced EC cycle progression. Our findings demonstrate the force-specificity of the activation of Smad1/5 and its contribution to cell cycle progression in ECs induced by disturbed flow.


Assuntos
Aterosclerose/fisiopatologia , Ciclo Celular/fisiologia , Células Endoteliais/fisiologia , Regulação da Expressão Gênica/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Proteína Smad1/metabolismo , Estresse Mecânico , Animais , Aorta Abdominal/citologia , Aorta Abdominal/patologia , Apolipoproteínas E/genética , Fenômenos Biomecânicos , Vasos Coronários/citologia , Vasos Coronários/patologia , Ciclina A/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Ratos , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Taiwan
11.
Biochim Biophys Acta ; 1833(12): 3124-3133, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24021264

RESUMO

Mechanical forces induced by interstitial fluid flow in and surrounding tissues and by blood/lymphatic flow in vessels may modulate cancer cell invasion and metastasis and anticancer drug delivery. Our previous study demonstrated that laminar flow-induced shear stress induces G2/M arrest in tumor cells. However, whether shear stress modulates final cell fate remains unclear. In this study, we investigated the role of flow-induced shear stress in modulating the survival of four human tumor cell lines, i.e., Hep3B hepatocarcinoma cells, MG63 osteosarcoma cells, SCC25 oral squamous carcinoma cells, and A549 carcinomic alveolar basal epithelial cells. Laminar shear stress (LSS) ranging from 0.5 to 12dyn/cm(2) induced death of these four tumor cell lines. In contrast to LSS at 0.5dyn/cm(2), oscillatory shear stress (OSS) at 0.5±4dyn/cm(2) cannot induce cancer cell death. Both LSS and OSS had no effect on human normal hepatocyte, lung epithelial, and endothelial cells. Application of LSS to these four cell lines increased the percentage of cells stained positively for annexin V-FITC, with up-regulations of cleaved caspase-8, -9, and -3, and PARP. In addition, LSS also induced Hep3B cell autophagy, as detected by acidic vesicular organelle formation, LC3B transformation, and p62/SQSTM1 degradation. By transfecting with small interfering RNA, we found that the shear-induced apoptosis and autophagy are mediated by bone morphogenetic protein receptor type (BMPR)-IB, BMPR-specific Smad1 and Smad5, and p38 mitogen-activated protein kinase in Hep3B cells. Our findings provide insights into the molecular mechanisms by which shear stress induces apoptosis and autophagy in tumor cells.


Assuntos
Apoptose , Autofagia , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Neoplasias/patologia , Proteínas Smad/metabolismo , Estresse Mecânico , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Neoplasias/enzimologia , Transdução de Sinais , Proteína Smad1/metabolismo , Proteína Smad5/metabolismo
12.
Development ; 138(17): 3803-12, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21795280

RESUMO

Cell sorting involves the segregation of two cell populations into `immiscible' adjacent tissues with smooth borders. Echinoid (Ed), a nectin ortholog, is an adherens junction protein in Drosophila, and cells mutant for ed sort out from the surrounding wild-type cells. However, it remains unknown which factors trigger cell sorting. Here, we dissect the sequence of this process and find that cell sorting occurs when differential expression of Ed triggers the assembly of actomyosin cable. Conversely, Ed-mediated cell sorting can be rescued by recruitment of Ed, via homophilic or heterophilic interactions, to the wild-type cell side of the clonal interface, even when differential Ed expression persists. We found, unexpectedly, that when actomyosin cable was largely absent, differential adhesion was sufficient to cause limited cell segregation but with a jagged tissue border (imperfect sorting). We propose that Ed-mediated cell sorting is driven both by differential Ed adhesion that induces cell segregation with a jagged border and by actomyosin cable assembly at the interface that smoothens this border.


Assuntos
Actomiosina/metabolismo , Moléculas de Adesão Celular/metabolismo , Adesão Celular/fisiologia , Agregação Celular/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila/citologia , Drosophila/metabolismo , Proteínas Repressoras/metabolismo , Actomiosina/genética , Animais , Adesão Celular/genética , Moléculas de Adesão Celular/genética , Agregação Celular/genética , Drosophila/genética , Proteínas de Drosophila/genética , Endocitose/genética , Endocitose/fisiologia , Proteínas Repressoras/genética
13.
Nucleic Acids Res ; 40(1): 449-60, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21908401

RESUMO

Trichomonas vaginalis Myb3 transcription factor (tvMyb3) recognizes the MRE-1 promoter sequence and regulates ap65-1 gene, which encodes a hydrogenosomal malic enzyme that may play a role in the cytoadherence of the parasite. Here, we identified tvMyb3(53-180) as the essential fragment for DNA recognition and report the crystal structure of tvMyb3(53-180) bound to MRE-1 DNA. The N-terminal fragment adopts the classical conformation of an Myb DNA-binding domain, with the third helices of R2 and R3 motifs intercalating in the major groove of DNA. The C-terminal extension forms a ß-hairpin followed by a flexible tail, which is stabilized by several interactions with the R3 motif and is not observed in other Myb proteins. Interestingly, this unique C-terminal fragment does not stably connect with DNA in the complex structure but is involved in DNA binding, as demonstrated by NMR chemical shift perturbation, (1)H-(15)N heteronuclear-nuclear Overhauser effect and intermolecular paramagnetic relaxation enhancement. Site-directed mutagenesis also revealed that this C-terminal fragment is crucial for DNA binding, especially the residue Arg(153) and the fragment K(170)KRK(173). We provide a structural basis for MRE-1 DNA recognition and suggest a possible post-translational regulation of tvMyb3 protein.


Assuntos
Proteínas de Ligação a DNA/química , Regiões Promotoras Genéticas , Proteínas de Protozoários/química , Fatores de Transcrição/química , Trichomonas vaginalis , Sequência de Aminoácidos , Sítios de Ligação , Cristalografia por Raios X , DNA de Protozoário/química , Proteínas de Ligação a DNA/genética , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas de Protozoários/genética , Alinhamento de Sequência , Fatores de Transcrição/genética
14.
J Cell Mol Med ; 17(4): 437-48, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23551392

RESUMO

Vascular endothelial cells (ECs) and smooth muscle cells (VSMCs) are constantly exposed to haemodynamic forces, including blood flow-induced fluid shear stress and cyclic stretch from blood pressure. These forces modulate vascular cell gene expression and function and, therefore, influence vascular physiology and pathophysiology in health and disease. Epigenetics, including DNA methylation, histone modification/chromatin remodelling and RNA-based machinery, refers to the study of heritable changes in gene expression that occur without changes in the DNA sequence. The role of haemodynamic force-induced epigenetic modifications in the regulation of vascular gene expression and function has recently been elucidated. This review provides an introduction to the epigenetic concepts that relate to vascular physiology and pathophysiology. Through the studies of gene expression, cell proliferation, angiogenesis, migration and pathophysiological states, we present a conceptual framework for understanding how mechanical force-induced epigenetic modifications work to control vascular gene expression and function and, hence, the development of vascular disorders. This research contributes to our knowledge of how the mechanical environment impacts the chromatin state of ECs and VSMCs and the consequent cellular behaviours.


Assuntos
Epigênese Genética , Neovascularização Patológica/genética , Neovascularização Fisiológica/genética , Animais , Fenômenos Biomecânicos , Montagem e Desmontagem da Cromatina , Metilação de DNA , Hemodinâmica , Histona Desacetilases/fisiologia , Histonas/metabolismo , Humanos , MicroRNAs/fisiologia , Neovascularização Patológica/metabolismo , Processamento de Proteína Pós-Traducional , Estresse Fisiológico
15.
Development ; 137(5): 745-54, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20110316

RESUMO

Planar cell polarity (PCP) refers to a second polarity axis orthogonal to the apicobasal axis in the plane of the epithelium. The molecular link between apicobasal polarity and PCP is largely unknown. During Drosophila eye development, differentiated photoreceptors form clusters that rotate independently of the surrounding interommatidial cells (ICs). Here, we demonstrate that both Echinoid (Ed), an adherens junction-associated cell adhesion molecule, and Flamingo (Fmi), a PCP determinant, are endocytosed via a clathrin-mediated pathway in ICs. Interestingly, we found that Ed binds the AP-2 adaptor and is required for the internalization of Fmi into ICs. Loss of ed led to increased amounts of Fmi on the cell membrane of non-rotating ICs and also to the misrotation of photoreceptor clusters. Importantly, overexpression of fmi in ICs alone was sufficient to cause misrotation of the adjacent photoreceptor clusters. Together, we propose that Ed, when internalized by AP-2, undergoes co-endocytosis with, and thereby decreases, Fmi levels on non-rotating ICs to permit correct rotation of ommatidial clusters. Thus, co-endocytosis of Ed and Fmi provides a link between apicobasal polarity and PCP.


Assuntos
Padronização Corporal , Caderinas/metabolismo , Moléculas de Adesão Celular/fisiologia , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/fisiologia , Drosophila/crescimento & desenvolvimento , Olho/crescimento & desenvolvimento , Proteínas Repressoras/fisiologia , Animais , Animais Geneticamente Modificados , Padronização Corporal/genética , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Polaridade Celular/genética , Polaridade Celular/fisiologia , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Endocitose/genética , Receptores ErbB/metabolismo , Olho/metabolismo , Receptores de Peptídeos de Invertebrados/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
16.
Eukaryot Cell ; 11(12): 1441-50, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23042127

RESUMO

In Trichomonas vaginalis, a novel nuclear localization signal spanning the folded R2R3 DNA-binding domain of a Myb2 protein was previously identified. To study whether a similar signal is used for nuclear translocation by other Myb proteins, nuclear translocation of Myb3 was examined in this report. When overexpressed, hemagglutinin-tagged Myb3 was localized to nuclei of transfected cells, with a cellular distribution similar to that of endogenous Myb3. Fusion to a bacterial tetracycline repressor, R2R3, of Myb3 that spans amino acids (aa) 48 to 156 was insufficient for nuclear translocation of the fusion protein, unless its C terminus was extended to aa 167. The conserved isoleucine in helix 2 of R2R3, which is important for Myb2's structural integrity in maintaining DNA-binding activity and nuclear translocation, was also vital for the former activity of Myb3, but less crucial for the latter. Sequential nuclear influx and efflux of Myb3, which require further extension of the nuclear localization signal to aa 180, were immediately induced after iron repletion. Sequence elements that regulate nuclear translocation with cytoplasmic retention, nuclear influx, and nuclear efflux were identified within the C-terminal tail. These results suggest that the R2R3 DNA-binding domain also serves as a common module for the nuclear translocation of both Myb2 and Myb3, but there are intrinsic differences between the two nuclear localization signals.


Assuntos
Núcleo Celular/metabolismo , Ferro/metabolismo , Proteínas de Protozoários/metabolismo , Fatores de Transcrição/metabolismo , Trichomonas vaginalis/metabolismo , Transporte Ativo do Núcleo Celular , Sítios de Ligação , Sinais de Localização Nuclear , Estrutura Terciária de Proteína , Transporte Proteico , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Fatores de Transcrição/química , Fatores de Transcrição/genética , Trichomonas vaginalis/genética , Regulação para Cima
17.
Plast Surg (Oakv) ; 31(1): 91-97, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36755818

RESUMO

Isolated congenital alar rim defects are extremely rare, and there has been no standard technique for the reconstruction of remarkable aesthetic deformity. Herein, we introduce a trifoliate flap for the correction of isolated congenital alar rim defects in pediatric patients. Fifteen cases undergoing nasal alar sulcus rotation flap surgery were analyzed retrospectively. This rotation flap including 3 triangles was a modified flap based on prior studies. Clinical medical notes and photographs were reviewed. Patients' (or their parents) reported satisfactions with aesthetic outcome were also evaluated during the post-operative follow-up period. In all patients, the isolated congenital alar rim defects were successfully reconstructed. The rotation flap survived and the wound healed primarily. The follow-up period ranged from 6 to 22 months (average 11 months). There were no incidents of flap loss, step-off deformities, nasal obstruction, or alar retraction. At follow-up of post-operative 3 months, pale red scars were observed in the operative area in few patients (2/15). However, these scars gradually became invisible at post-operative 6 months. All patients (or their parents) were satisfied with the aesthetic outcome of this operation. This newly designed trifoliate flap can be an alternative method for the reconstruction of isolated congenital alar rim defects in pediatric patients. The scars of this procedure can be unobvious with fine surgical suture.


Contexte: Les anomalies congénitales isolées du pourtour de l'aile du nez sont extrêmement rares et il n'existe aucune technique de référence pour la reconstruction de cette difformité esthétique notable. Nous présentons ici un volet trifolié pour la correction des anomalies congénitales du pourtour de l'aile du nez chez des patients pédiatriques. Méthodes: Quinze cas de patients subissant une chirurgie avec rotation de lambeau de sillon de l'aile du nez ont été analysés rétrospectivement. Ce lambeau de rotation comportant trois triangles était une version modifiée d'un lambeau utilisé dans des études précédentes. Les notes médicales cliniques et les photographies ont été analysées. La satisfaction exprimée par les patients (ou leurs parents) à propos du résultat esthétique a été également évaluée au cours de la période de suivi postopératoire. Résultats: L'anomalie congénitale isolée du pourtour de l'aile du nez a été réparée avec succès chez tous les patients. Le lambeau de rotation a survécu et la plaie a guéri d'emblée: la durée de la période de suivi allait de 6 mois à 22 mois (moyenne: 11 mois). Il n'y a pas eu d'incidents de perte du lambeau, de difformité en marche d'escalier, d'obstruction nasale ou de rétraction de l'aile du nez. Au suivi postopératoire de 3 mois, des cicatrices rouge pâle ont été observées dans la zone opératoire de quelques patients (2/15). Cependant, ces cicatrices sont devenues progressivement invisibles à la visite postopératoire de 6 mois. Tous les patients (ou leurs parents) ont été satisfaits du résultat esthétique de cette opération. Conclusion: Ce lambeau trifolié nouvellement conçu peut être une méthode de substitution pour la reconstruction des anomalies congénitales isolées du pourtour de l'aile du nez chez des patients pédiatriques. Les cicatrices secondaires à cette opération peuvent être non évidentes avec une suture chirurgicale fine.

18.
Eukaryot Cell ; 10(12): 1607-17, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22021237

RESUMO

Nuclear proteins usually contain specific peptide sequences, referred to as nuclear localization signals (NLSs), for nuclear import. These signals remain unexplored in the protozoan pathogen, Trichomonas vaginalis. The nuclear import of a Myb2 transcription factor was studied here using immunodetection of a hemagglutinin-tagged Myb2 overexpressed in the parasite. The tagged Myb2 was localized to the nucleus as punctate signals. With mutations of its polybasic sequences, 48KKQK51 and 61KR62, Myb2 was localized to the nucleus, but the signal was diffusive. When fused to a C-terminal non-nuclear protein, the Myb2 sequence spanning amino acid (aa) residues 48 to 143, which is embedded within the R2R3 DNA-binding domain (aa 40 to 156), was essential and sufficient for efficient nuclear import of a bacterial tetracycline repressor (TetR), and yet the transport efficiency was reduced with an additional fusion of a firefly luciferase to TetR, while classical NLSs from the simian virus 40 T-antigen had no function in this assay system. Myb2 nuclear import and DNA-binding activity were substantially perturbed with mutation of a conserved isoleucine (I74) in helix 2 to proline that altered secondary structure and ternary folding of the R2R3 domain. Disruption of DNA-binding activity alone by point mutation of a lysine residue, K51, preceding the structural domain had little effect on Myb2 nuclear localization, suggesting that nuclear translocation of Myb2, which requires an ordered structural domain, is independent of its DNA binding activity. These findings provide useful information for testing whether myriad Mybs in the parasite use a common module to regulate nuclear import.


Assuntos
Núcleo Celular/metabolismo , Proteínas de Protozoários/metabolismo , Fatores de Transcrição/metabolismo , Trichomonas vaginalis/metabolismo , Transporte Ativo do Núcleo Celular , Sequência de Aminoácidos , Substituição de Aminoácidos , Sequência Conservada , DNA/química , Componentes do Gene , Luciferases de Vaga-Lume/química , Luciferases de Vaga-Lume/metabolismo , Dados de Sequência Molecular , Sinais de Localização Nuclear , Mapeamento de Peptídeos , Ligação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Transporte Proteico , Proteínas de Protozoários/química , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Transcrição/química
19.
Protein Sci ; 31(5): e4286, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35481641

RESUMO

In Staphylococcus aureus, vancomycin-resistance-associated response regulator (VraR) is a part of the VraSR two-component system, which is responsible for activating a cell wall-stress stimulon in response to an antibiotic that inhibits cell wall formation. Two VraR-binding sites have been identified: R1 and R2 in the vraSR operon control region. However, the binding of VraR to a promoter DNA enhancing downstream gene expression remains unclear. VraR contains a conserved N-terminal receiver domain (VraRN ) connected to a C-terminal DNA binding domain (VraRC ) with a flexible linker. Here, we present the crystal structure of VraRC alone and in complex with R1-DNA in 1.87- and 2.0-Å resolution, respectively. VraRC consisting of four α-helices forms a dimer when interacting with R1-DNA. In the VraRC -DNA complex structure, Mg2+ ion is bound to Asp194. Biolayer interferometry experiments revealed that the addition of Mg2+ to VraRC enhanced its DNA binding affinity by eightfold. In addition, interpretation of NMR titrations between VraRC with R1- and R2-DNA revealed the essential residues that might play a crucial role in interacting with DNA of the vraSR operon. The structural information could help in designing and screening potential therapeutics/inhibitors to deal with antibiotic-resistant S. aureus via targeting VraR.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Staphylococcus aureus , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/química , DNA/metabolismo , Proteínas de Ligação a DNA/química , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/metabolismo , Staphylococcus aureus/química , Staphylococcus aureus/genética , Vancomicina/farmacologia
20.
Database (Oxford) ; 20222022 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-35277958

RESUMO

Organ fibrosis represents a vital health threat that substantially contributes to yearly mortality rates. While a considerable amount of research has been conducted on fibrosis, these reports have only focused on specific organs as affected within distinct disorders. Accordingly, results from such studies have been unable to provide a comprehensive understanding of the pathological processes involved. Here, we describe the development of FibROAD, an open-access database that integrates evidence from fibrosis-associated disorders as obtained from both the literature and multi-omics data. This resource will greatly assist both researchers and clinicians in the comprehension and treatment of this condition. FibROAD currently involves an assembly of 232 strong evidence-based fibrosis-related genes (FRGs) as garnered from 909 PubMed publications and contains lists of multi-omics data from > 4000 samples including RNA-seq, single-cell RNA-seq, miRNA-seq, ChIP-seq, ATAC-seq MeDIP-seq and MBD-seq as obtained from 17 different organs in 5 species. Results from integrative analyses as obtained using FibROAD have demonstrated that FRGs can be indicators for a wide range of organ fibrosis and reveal potential pro-fibrotic candidate genes for fibrosis research. In conclusion, FibROAD serves as a convenient platform where researchers can acquire integrated evidence and a more comprehensive understanding of fibrosis-related disorders. Database URL  https://www.fibroad.org.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação , Bases de Dados Factuais , Fibrose , Humanos , RNA-Seq , Análise de Sequência
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