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1.
J Infect ; 85(5): 557-564, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36058413

RESUMEN

OBJECTIVES: To describe the risk factors for SARS-CoV-2 infection in UK healthcare workers (HCWs). METHODS: We conducted a prospective sero-epidemiological study of HCWs at a major UK teaching hospital using a SARS-CoV-2 immunoassay. Risk factors for seropositivity were analysed using multivariate logistic regression. RESULTS: 410/5,698 (7·2%) staff tested positive for SARS-CoV-2 antibodies. Seroprevalence was higher in those working in designated COVID-19 areas compared with other areas (9·47% versus 6·16%) Healthcare assistants (aOR 2·06 [95%CI 1·14-3·71]; p=0·016) and domestic and portering staff (aOR 3·45 [95% CI 1·07-11·42]; p=0·039) had significantly higher seroprevalence than other staff groups after adjusting for age, sex, ethnicity and COVID-19 working location. Staff working in acute medicine and medical sub-specialities were also at higher risk (aOR 2·07 [95% CI 1·31-3·25]; p<0·002). Staff from Black, Asian and minority ethnic (BAME) backgrounds had an aOR of 1·65 (95% CI 1·32 - 2·07; p<0·001) compared to white staff; this increased risk was independent of COVID-19 area working. The only symptoms significantly associated with seropositivity in a multivariable model were loss of sense of taste or smell, fever, and myalgia; 31% of staff testing positive reported no prior symptoms. CONCLUSIONS: Risk of SARS-CoV-2 infection amongst HCWs is highly heterogeneous and influenced by COVID-19 working location, role, age and ethnicity. Increased risk amongst BAME staff cannot be accounted for solely by occupational factors.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Antivirales , COVID-19/epidemiología , Personal de Salud , Hospitales de Enseñanza , Humanos , Estudios Prospectivos , Factores de Riesgo , Estudios Seroepidemiológicos , Reino Unido/epidemiología
3.
Nurs Educ Perspect ; 43(4): 249-251, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34516482

RESUMEN

ABSTRACT: Research has demonstrated the ability of evidence-based practice (EBP) to enhance quality and reliability of health care, improve health outcomes, and reduce cost and health disparities. Nursing curricula often lack best practices for teaching EBP, as well as actual EBP course content, objectives, and activities, to advance student understanding of EBP. The unfortunate results are nurse graduates who do not value or perceive that they can use EBP. This study implemented an EBP assignment assessing clinical practice guidelines as a means of improving EBP beliefs in senior-level nursing students.


Asunto(s)
Estudiantes de Enfermería , Curriculum , Atención a la Salud , Enfermería Basada en la Evidencia , Práctica Clínica Basada en la Evidencia/educación , Humanos , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
4.
Nature ; 596(7872): 417-422, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34192737

RESUMEN

Although two-dose mRNA vaccination provides excellent protection against SARS-CoV-2, there is little information about vaccine efficacy against variants of concern (VOC) in individuals above eighty years of age1. Here we analysed immune responses following vaccination with the BNT162b2 mRNA vaccine2 in elderly participants and younger healthcare workers. Serum neutralization and levels of binding IgG or IgA after the first vaccine dose were lower in older individuals, with a marked drop in participants over eighty years old. Sera from participants above eighty showed lower neutralization potency against the B.1.1.7 (Alpha), B.1.351 (Beta) and P.1. (Gamma) VOC than against the wild-type virus and were more likely to lack any neutralization against VOC following the first dose. However, following the second dose, neutralization against VOC was detectable regardless of age. The frequency of SARS-CoV-2 spike-specific memory B cells was higher in elderly responders (whose serum showed neutralization activity) than in non-responders after the first dose. Elderly participants showed a clear reduction in somatic hypermutation of class-switched cells. The production of interferon-γ and interleukin-2 by SARS-CoV-2 spike-specific T cells was lower in older participants, and both cytokines were secreted primarily by CD4 T cells. We conclude that the elderly are a high-risk population and that specific measures to boost vaccine responses in this population are warranted, particularly where variants of concern are circulating.


Asunto(s)
Envejecimiento/inmunología , Vacunas contra la COVID-19/inmunología , Inmunidad , SARS-CoV-2/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/sangre , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Autoanticuerpos/inmunología , Linfocitos B/citología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Vacuna BNT162 , Vacunas contra la COVID-19/administración & dosificación , Femenino , Personal de Salud , Humanos , Inmunidad/genética , Inmunización Secundaria , Inmunoglobulina A/inmunología , Cambio de Clase de Inmunoglobulina , Inmunoglobulina G/genética , Inmunoglobulina G/inmunología , Memoria Inmunológica/inmunología , Inflamación/sangre , Inflamación/inmunología , Interferón gamma/inmunología , Interleucina-2/inmunología , Masculino , Persona de Mediana Edad , Hipermutación Somática de Inmunoglobulina , Glicoproteína de la Espiga del Coronavirus/inmunología , Linfocitos T/inmunología , Vacunación , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/inmunología , Vacunas de ARNm
5.
Nature ; 593(7857): 136-141, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33706364

RESUMEN

Transmission of SARS-CoV-2 is uncontrolled in many parts of the world; control is compounded in some areas by the higher transmission potential of the B.1.1.7 variant1, which has now been reported in 94 countries. It is unclear whether the response of the virus to vaccines against SARS-CoV-2 on the basis of the prototypic strain will be affected by the mutations found in B.1.1.7. Here we assess the immune responses of individuals after vaccination with the mRNA-based vaccine BNT162b22. We measured neutralizing antibody responses after the first and second immunizations using pseudoviruses that expressed the wild-type spike protein or a mutated spike protein that contained the eight amino acid changes found in the B.1.1.7 variant. The sera from individuals who received the vaccine exhibited a broad range of neutralizing titres against the wild-type pseudoviruses that were modestly reduced against the B.1.1.7 variant. This reduction was also evident in sera from some patients who had recovered from COVID-19. Decreased neutralization of the B.1.1.7 variant was also observed for monoclonal antibodies that target the N-terminal domain (9 out of 10) and the receptor-binding motif (5 out of 31), but not for monoclonal antibodies that recognize the receptor-binding domain that bind outside the receptor-binding motif. Introduction of the mutation that encodes the E484K substitution in the B.1.1.7 background to reflect a newly emerged variant of concern (VOC 202102/02) led to a more-substantial loss of neutralizing activity by vaccine-elicited antibodies and monoclonal antibodies (19 out of 31) compared with the loss of neutralizing activity conferred by the mutations in B.1.1.7 alone. The emergence of the E484K substitution in a B.1.1.7 background represents a threat to the efficacy of the BNT162b2 vaccine.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Vacunas contra la COVID-19/inmunología , COVID-19/inmunología , COVID-19/terapia , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Vacunas Sintéticas/inmunología , Anciano , Anciano de 80 o más Años , Enzima Convertidora de Angiotensina 2/metabolismo , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/aislamiento & purificación , Anticuerpos Neutralizantes/aislamiento & purificación , Anticuerpos Antivirales/aislamiento & purificación , COVID-19/metabolismo , COVID-19/virología , Femenino , Células HEK293 , Humanos , Evasión Inmune/genética , Evasión Inmune/inmunología , Inmunización Pasiva , Masculino , Persona de Mediana Edad , Modelos Moleculares , Mutación , Pruebas de Neutralización , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Vacunas Sintéticas/administración & dosificación , Sueroterapia para COVID-19 , Vacunas de ARNm
6.
medRxiv ; 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33619509

RESUMEN

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) transmission is uncontrolled in many parts of the world, compounded in some areas by higher transmission potential of the B1.1.7 variant now seen in 50 countries. It is unclear whether responses to SARS-CoV-2 vaccines based on the prototypic strain will be impacted by mutations found in B.1.1.7. Here we assessed immune responses following vaccination with mRNA-based vaccine BNT162b2. We measured neutralising antibody responses following a single immunization using pseudoviruses expressing the wild-type Spike protein or the 8 amino acid mutations found in the B.1.1.7 spike protein. The vaccine sera exhibited a broad range of neutralising titres against the wild-type pseudoviruses that were modestly reduced against B.1.1.7 variant. This reduction was also evident in sera from some convalescent patients. Decreased B.1.1.7 neutralisation was also observed with monoclonal antibodies targeting the N-terminal domain (9 out of 10), the Receptor Binding Motif (RBM) (5 out of 31), but not in neutralising mAbs binding outside the RBM. Introduction of the E484K mutation in a B.1.1.7 background to reflect newly emerging viruses in the UK led to a more substantial loss of neutralising activity by vaccine-elicited antibodies and mAbs (19 out of 31) over that conferred by the B.1.1.7 mutations alone. E484K emergence on a B.1.1.7 background represents a threat to the vaccine BNT162b.

7.
J Am Assoc Nurse Pract ; 33(10): 831-837, 2020 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-32740332

RESUMEN

BACKGROUND: Family caregivers who care for individuals with dementia are more likely to develop chronic stress, major depression, anxiety, and physical health disorders and they have a higher mortality rate compared with the general population. LOCAL PROBLEM: Caregivers are at an increased risk of physical and mental disorders. Many report that they are fatigued and need more forms of support. METHODS: This project involved a convenience sample of 35 family caregivers who cared for family with dementia. Prequestionnaires and postquestionnaires were used to determine improvements in caregiver health and well-being and caregiver resources for supportive services as well as reduction in caregiver stress. INTERVENTIONS: An evidence-based educational class was developed and implemented based on the Family Care Alliance (FCA): Taking Care of YOU: Self-Care for Family Caregivers Toolkit. The project aimed to (1) assess two FCA recommended domains: caregiver health and well-being and caregiver resources for supportive services and (2) reduce caregiver stress. RESULTS: Stress Inventory results showed notable change in high risk/low risk categorization from pretest to posttest. At pretest, 31 caregivers were categorized as at high risk for unhealthy levels of stress, but posttest showed only 9 caregivers were so categorized. Approximately, 70% of those at high risk at pretest were categorized as low risk at posttest. CONCLUSIONS: This project validated that evidence-based educational interventions can improve caregiver knowledge and self-care. Continued support may be promoted by incorporating education and offering resource brochures to caregivers during primary care visits.

8.
Cancer Res ; 80(6): 1234-1245, 2020 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-32046982

RESUMEN

Estrogen signaling through estrogen receptor alpha (ER) plays a major role in endometrial cancer risk and progression, however, the molecular mechanisms underlying ER's regulatory role in endometrial cancer are poorly understood. In breast cancer cells, ER genomic binding is enabled by FOXA1 and GATA3, but the transcription factors that control ER genomic binding in endometrial cancer cells remain unknown. We previously identified ETV4 as a candidate factor controlling ER genomic binding in endometrial cancer cells, and here we explore the functional importance of ETV4. Homozygous deletion of ETV4, using CRISPR/Cas9, led to greatly reduced ER binding at the majority of loci normally bound by ER. Consistent with the dramatic loss of ER binding, the gene expression response to estradiol was dampened for most genes. ETV4 contributes to estrogen signaling in two distinct ways. ETV4 loss affects chromatin accessibility at some ER bound loci and impairs ER nuclear translocation. The diminished estrogen signaling upon ETV4 deletion led to decreased growth, particularly in 3D culture, where hollow organoids were formed and in vivo in the context of estrogen-dependent growth. These results show that ETV4 plays an important role in estrogen signaling in endometrial cancer cells. SIGNIFICANCE: Estrogen receptor alpha (ER) is a key oncogene in endometrial cancer. This study uncovers ETV4 as an important factor in controlling the activity of ER and the growth of endometrial cancer cells. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/6/1234/F1.large.jpg.


Asunto(s)
Neoplasias Endometriales/genética , Receptor alfa de Estrógeno/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas Proto-Oncogénicas c-ets/metabolismo , Animales , Línea Celular Tumoral , Núcleo Celular/metabolismo , Cromatina/metabolismo , Secuenciación de Inmunoprecipitación de Cromatina , Citoplasma/metabolismo , Neoplasias Endometriales/patología , Estradiol/metabolismo , Femenino , Técnicas de Inactivación de Genes , Humanos , Ratones , Proteínas Proto-Oncogénicas c-ets/genética , RNA-Seq , Transducción de Señal/genética , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Creat Nurs ; 25(2): 148-153, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-31085669

RESUMEN

Professional nurses are called to provide nursing care using an evidence-based approach. Health-care professionals are challenged to break away from old traditions and search for ways to improve health. Evidence-based practice (EBP) must be threaded throughout nursing curricula to produce critically-thinking professional nurses who will be meeting new and significant health-care challenges. Nursing education must be grounded in the translation of current evidence into practice. Nurse educators must acknowledge the obstacles faced when teaching concepts of research to students who have chosen a practice-focused career. The words evidence-based practice may be intimidating to nursing students. Nurse educators must shift this paradigm to invite students to realize that EBP is an integral component of modern health care that bridges the gap between health-care practices and improved patient outcomes. Faculty in a baccalaureate Adult Health course developed a unique approach inviting students to apply evidence to their student clinical experiences. Survey results showed that this innovative approach increased students' "excellent" or "good" understanding toward EBP concepts from pre-implementation scores of 46% to post-implementation scores of 94%. This active learning strategy allows students to "walk the walk" of EBP rather than simply listen to the "talk."


Asunto(s)
Curriculum , Bachillerato en Enfermería/organización & administración , Enfermería Basada en la Evidencia/educación , Personal de Enfermería en Hospital/psicología , Aprendizaje Basado en Problemas/organización & administración , Estudiantes de Enfermería/psicología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto Joven
10.
Worldviews Evid Based Nurs ; 16(2): 142-150, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30861333

RESUMEN

BACKGROUND: Diabetes is a major health concern in the United States. Poor quality diabetes care leads to negative outcomes affecting patients and healthcare systems. Research shows evidence-based clinical practice guidelines from the American Diabetes Association, Standards of Medical Care in Diabetes-2017, have improved outcomes in management of diabetes. AIMS: The aim of this improvement project was to improve diabetes care and outcomes in a primary care clinic serving a Hispanic community in Miami-Dade, Florida. Specific objectives of the project were to improve primary care provider attitudes and knowledge of American Diabetes Association guidelines and outcomes in patients with diabetes. METHODS: This two-phase quality improvement project used a pre- and post-test study design. In Phase I, the Diabetes Attitude Survey was administered to determine primary care provider attitudes and knowledge of guidelines. Based on survey results, a 2-hr educational intervention was developed to inform providers regarding the American Diabetes Association clinical practice guidelines. In Phase II, data were collected for 19 clinical quality diabetes outcome measures from agency reports. Guidelines were implemented into practice, and intervention effectiveness was evaluated. RESULTS: Statistical analysis (paired-sample t-test) revealed postintervention improvement in provider knowledge and attitudes, and patient outcomes. Findings suggest the intervention led to improvements in the quality of diabetes care in this Hispanic clinic. LINKING EVIDENCE TO ACTION: Project success supports the importance of evidence-based clinical practice guideline use to achieve better diabetes outcomes. Implementation of the American Diabetes Association Standards of Medical Care in Diabetes to improve patient outcomes is strongly recommended. It is equally important that clinical agencies educate and update primary care providers to achieve best practice and best patient diabetes outcomes. Other healthcare professionals can use this project design to provide culturally competent care to patients with diabetes.


Asunto(s)
Diabetes Mellitus/terapia , Guías como Asunto , Desarrollo de Programa/métodos , Hispánicos o Latinos/psicología , Humanos , Atención Primaria de Salud/métodos , Salud Pública/métodos , Salud Pública/tendencias , Mejoramiento de la Calidad , Estados Unidos
11.
J Mol Biol ; 431(3): 593-614, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30597162

RESUMEN

The eukaryotic transcription factor ETS1 is regulated by an intrinsically disordered serine-rich region (SRR) that transiently associates with the adjacent ETS domain to inhibit DNA binding. In this study, we further elucidated the physicochemical basis for ETS1 autoinhibition by characterizing the interaction of its ETS domain with a series of synthetic peptides corresponding to the SRR. Binding is driven by the hydrophobic effect and enhanced electrostatically by phosphorylation of serines adjacent to aromatic residues in the amphipathic SRR. Structural characterization of the dynamic peptide/protein complex by NMR spectroscopy and X-ray crystallography revealed multiple modes of binding that lead to autoinhibition by synergistically blocking the DNA-binding interface of the ETS domain and stabilizing an appended helical inhibitory module against allosterically induced unfolding. Consistent with these conclusions, the SRR peptide does not interact with DNA-bound ETS1. In addition, we found that the ETS1 SRR phosphopeptide binds to distantly related PU.1 in vitro, indicating that autoinhibition exploits features of the ETS domain that are conserved across this family of transcription factors.


Asunto(s)
ADN/metabolismo , Unión Proteica/fisiología , Proteína Proto-Oncogénica c-ets-1/metabolismo , Factores de Transcripción/metabolismo , Sitios de Unión/fisiología , Biofisica/métodos , Cristalografía por Rayos X/métodos , Espectroscopía de Resonancia Magnética/métodos , Modelos Moleculares , Fosforilación , Conformación Proteica , Dominios Proteicos/fisiología , Serina/metabolismo
12.
SLAS Discov ; 24(1): 77-85, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30204534

RESUMEN

ETS transcription factors from the ERG and ETV1/4/5 subfamilies are overexpressed in the majority of prostate cancer patients and contribute to disease progression. Here, we have developed two in vitro assays for the interaction of ETS transcription factors with DNA that are amenable to high-throughput screening. Using ETS1 as a model, we applied these assays to screen 110 compounds derived from a high-throughput virtual screen. We found that the use of lower-affinity DNA binding sequences, similar to those that ERG and ETV1 bind to in prostate cells, allowed for higher inhibition from many of these test compounds. Further pilot experiments demonstrated that the in vitro assays are robust for ERG, ETV1, and ETV5, three of the ETS transcription factors that are overexpressed in prostate cancer.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento/métodos , Proteínas Proto-Oncogénicas c-ets/genética , Línea Celular Tumoral , Proteínas de Unión al ADN/genética , Humanos , Masculino , Próstata/metabolismo , Neoplasias de la Próstata/genética , Regulador Transcripcional ERG/genética
13.
J Biol Chem ; 293(48): 18624-18635, 2018 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-30315111

RESUMEN

Many different transcription factors (TFs) regulate gene expression in a combinatorial fashion, often by binding in close proximity to each other on composite cis-regulatory DNA elements. Here, we investigated how ETS TFs bind with the AP1 TFs JUN-FOS at composite DNA-binding sites. DNA-binding ability with JUN-FOS correlated with the phenotype of ETS proteins in prostate cancer. We found that the oncogenic ETS-related gene (ERG) and ETS variant (ETV) 1/4/5 subfamilies co-occupy ETS-AP1 sites with JUN-FOS in vitro, whereas JUN-FOS robustly inhibited DNA binding by the tumor suppressors ETS homologous factor (EHF) and SAM pointed domain-containing ETS TF (SPDEF). EHF bound ETS-AP1 DNA with tighter affinity than ERG in the absence of JUN-FOS, possibly enabling EHF to compete with ERG and JUN-FOS for binding to ETS-AP1 sites. Genome-wide mapping of EHF- and ERG-binding sites in prostate epithelial cells revealed that EHF is preferentially excluded from closely spaced ETS-AP1 DNA sequences. Structural modeling and mutational analyses indicated that adjacent positively charged surfaces from EHF and JUN-FOS use electrostatic repulsion to disfavor simultaneous DNA binding. Conservation of positive residues on the JUN-FOS interface identified E74-like ETS TF 1 (ELF1) as an additional ETS TF exhibiting anticooperative DNA binding with JUN-FOS, and we found that ELF1 is frequently down-regulated in prostate cancer. In summary, divergent electrostatic features of ETS TFs at their JUN-FOS interface enable distinct binding events at ETS-AP1 DNA sites, which may drive specific targeting of ETS TFs to facilitate distinct transcriptional programs.


Asunto(s)
ADN/metabolismo , Proteínas Proto-Oncogénicas c-ets/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-jun/metabolismo , Electricidad Estática , Sitios de Unión , Humanos , Unión Proteica , Factores de Transcripción/metabolismo , Regulador Transcripcional ERG/metabolismo
14.
Worldviews Evid Based Nurs ; 15(2): 152-154, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29266742

RESUMEN

This column shares the best evidence-based strategies and innovative ideas on how to facilitate the learning and implementation of EBP principles and processes by clinicians as well as nursing and interprofessional students. Guidelines for submission are available at https://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1741-6787.


Asunto(s)
Educación en Enfermería/métodos , Práctica Clínica Basada en la Evidencia/métodos , Educación en Enfermería/normas , Práctica Clínica Basada en la Evidencia/normas , Docentes de Enfermería/tendencias , Humanos , Evaluación de Procesos y Resultados en Atención de Salud/métodos
15.
J Prof Nurs ; 33(6): 417-421, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29157569

RESUMEN

The DNP curriculum prepares the graduate for evidence informed improvement translation through coursework integrating improvement, safety, and translation sciences. Innovative leadership skills are necessary to lead inter-professional unit-based and health system opportunities. Equipping the DNP with the necessary skills and competencies to accomplish any type of improvement translation requires exposure to the tools and techniques of these sciences with an emphasis in didactic content. With a foundational knowledge of the principles for improvement, translation and application will follow. It is imperative theoretical underpinnings of translational science are taught, and that the students be expected to apply these concepts in "real word" circumstances. Thus, the DNP student is afforded opportunities during their DNP program to participate in a "learning lab" for evidence informed improvement translation. In essence, the courses within the program are designed to allow conversion from theory into practice.


Asunto(s)
Conducta Cooperativa , Curriculum , Educación de Postgrado en Enfermería/organización & administración , Práctica Clínica Basada en la Evidencia , Liderazgo , Humanos , Estudiantes de Enfermería , Investigación Biomédica Traslacional
16.
J Mol Biol ; 429(20): 2975-2995, 2017 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-28728983

RESUMEN

The recruitment of transcriptional cofactors by sequence-specific transcription factors challenges the basis of high affinity and selective interactions. Extending previous studies that the N-terminal activation domain (AD) of ETV5 interacts with Mediator subunit 25 (MED25), we establish that similar, aromatic-rich motifs located both in the AD and in the DNA-binding domain (DBD) of the related ETS factor ETV4 interact with MED25. These ETV4 regions bind MED25 independently, display distinct kinetics, and combine to contribute to a high-affinity interaction of full-length ETV4 with MED25. High-affinity interactions with MED25 are specific for the ETV1/4/5 subfamily as other ETS factors display weaker binding. The AD binds to a single site on MED25 and the DBD interacts with three MED25 sites, allowing for simultaneous binding of both domains in full-length ETV4. MED25 also stimulates the in vitro DNA binding activity of ETV4 by relieving autoinhibition. ETV1/4/5 factors are often overexpressed in prostate cancer and genome-wide studies in a prostate cancer cell line indicate that ETV4 and MED25 occupy enhancers that are enriched for ETS-binding sequences and are both functionally important for the transcription of genes regulated by these enhancers. AP1-motifs, which bind JUN and FOS transcription factor families, were observed in MED25-occupied regions and JUN/FOS also contact MED25; FOS strongly binds to the same MED25 site as ETV4 AD and JUN interacts with the other two MED25 sites. In summary, we describe features of the multivalent ETV4- and AP1-MED25 interactions, thereby implicating these factors in the recruitment of MED25 to transcriptional control elements.


Asunto(s)
Proteínas E1A de Adenovirus/metabolismo , Complejo Mediador/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas E1A de Adenovirus/química , Línea Celular Tumoral , Ensayo de Cambio de Movilidad Electroforética , Humanos , Espectroscopía de Resonancia Magnética , Complejo Mediador/química , Modelos Biológicos , Simulación del Acoplamiento Molecular , Unión Proteica , Mapeo de Interacción de Proteínas , Proteínas Proto-Oncogénicas/química , Proteínas Proto-Oncogénicas c-ets , Proteínas Proto-Oncogénicas c-fos/química
17.
Nucleic Acids Res ; 45(5): 2223-2241, 2017 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-28161714

RESUMEN

Autoinhibition enables spatial and temporal regulation of cellular processes by coupling protein activity to surrounding conditions, often via protein partnerships or signaling pathways. We report the molecular basis of DNA-binding autoinhibition of ETS transcription factors ETV1, ETV4 and ETV5, which are often overexpressed in prostate cancer. Inhibitory elements that cooperate to repress DNA binding were identified in regions N- and C-terminal of the ETS domain. Crystal structures of these three factors revealed an α-helix in the C-terminal inhibitory domain that packs against the ETS domain and perturbs the conformation of its DNA-recognition helix. Nuclear magnetic resonance spectroscopy demonstrated that the N-terminal inhibitory domain (NID) is intrinsically disordered, yet utilizes transient intramolecular interactions with the DNA-recognition helix of the ETS domain to mediate autoinhibition. Acetylation of selected lysines within the NID activates DNA binding. This investigation revealed a distinctive mechanism for DNA-binding autoinhibition in the ETV1/4/5 subfamily involving a network of intramolecular interactions not present in other ETS factors. These distinguishing inhibitory elements provide a platform through which cellular triggers, such as protein-protein interactions or post-translational modifications, may specifically regulate the function of these oncogenic proteins.


Asunto(s)
Proteínas E1A de Adenovirus/química , Proteínas de Unión al ADN/química , ADN/química , Proteínas Intrínsecamente Desordenadas/química , Procesamiento Proteico-Postraduccional , Proteínas Proto-Oncogénicas/química , Factores de Transcripción/química , Acetilación , Proteínas E1A de Adenovirus/genética , Proteínas E1A de Adenovirus/metabolismo , Sitios de Unión , Clonación Molecular , Cristalografía por Rayos X , ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Proteínas Intrínsecamente Desordenadas/genética , Proteínas Intrínsecamente Desordenadas/metabolismo , Cinética , Lisina/química , Lisina/metabolismo , Unión Proteica , Conformación Proteica en Hélice alfa , Dominios y Motivos de Interacción de Proteínas , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-ets , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
18.
Elife ; 52016 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-27661449

RESUMEN

PAS domain containing protein kinase (Pask) is an evolutionarily conserved protein kinase implicated in energy homeostasis and metabolic regulation across eukaryotic species. We now describe an unexpected role of Pask in promoting the differentiation of myogenic progenitor cells, embryonic stem cells and adipogenic progenitor cells. This function of Pask is dependent upon its ability to phosphorylate Wdr5, a member of several protein complexes including those that catalyze histone H3 Lysine 4 trimethylation (H3K4me3) during transcriptional activation. Our findings suggest that, during myoblast differentiation, Pask stimulates the conversion of repressive H3K4me1 to activating H3K4me3 marks on the promoter of the differentiation gene myogenin (Myog) via Wdr5 phosphorylation. This enhances accessibility of the MyoD transcription factor and enables transcriptional activation of the Myog promoter to initiate muscle differentiation. Thus, as an upstream kinase of Wdr5, Pask integrates signaling cues with the transcriptional network to regulate the differentiation of progenitor cells.


Asunto(s)
Código de Histonas , N-Metiltransferasa de Histona-Lisina/metabolismo , Desarrollo de Músculos/fisiología , Músculos/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Animales , Diferenciación Celular , Línea Celular , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Células HEK293 , N-Metiltransferasa de Histona-Lisina/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular , Ratones , Células Madre Embrionarias de Ratones/metabolismo , Células Musculares/fisiología , Músculo Esquelético , Músculos/lesiones , Proteína MioD/metabolismo , Mioblastos/patología , Miogenina/genética , Miogenina/metabolismo , Fosforilación , Regiones Promotoras Genéticas , Proteínas Serina-Treonina Quinasas/genética , Células Madre , Activación Transcripcional
19.
Biochemistry ; 55(29): 4105-18, 2016 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-27362745

RESUMEN

The affinity of the Ets-1 transcription factor for DNA is autoinhibited by an intrinsically disordered serine-rich region (SRR) and a helical inhibitory module (IM) appended to its winged helix-turn-helix ETS domain. Using NMR spectroscopy, we investigated how Ets-1 recognizes specific versus nonspecific DNA, with a focus on the roles of protein dynamics and autoinhibition in these processes. Upon binding either DNA, the two marginally stable N-terminal helices of the IM predominantly unfold, but still sample partially ordered conformations. Also, on the basis of amide chemical shift perturbation mapping, Ets-1 associates with both specific and nonspecific DNA through the same canonical ETS domain interface. These interactions are structurally independent of the SRR, and thus autoinhibition does not impart DNA-binding specificity. However, relative to the pronounced NMR spectroscopic changes in Ets-1 resulting from specific DNA binding, the spectra of the nonspecific DNA complexes showed conformational exchange broadening and lacked several diagnostic amide and indole signals attributable to hydrogen bonding interactions seen in reported X-ray crystallographic structures of this transcription factor with its cognate DNA sequences. Such differences are highlighted by the chemical shift and relaxation properties of several interfacial lysine and arginine side chains. Collectively, these data support a general model in which Ets-1 interacts with nonspecific DNA via dynamic electrostatic interactions, whereas hydrogen bonding drives the formation of well-ordered complexes with specific DNA.


Asunto(s)
Proteína Proto-Oncogénica c-ets-1/química , Proteína Proto-Oncogénica c-ets-1/metabolismo , Animales , Arginina/química , Secuencia de Bases , ADN/química , ADN/metabolismo , Lisina/química , Ratones , Modelos Moleculares , Simulación de Dinámica Molecular , Resonancia Magnética Nuclear Biomolecular , Unión Proteica , Conformación Proteica , Estructura Secundaria de Proteína , Proteína Proto-Oncogénica c-ets-1/antagonistas & inhibidores , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Electricidad Estática
20.
J Mol Biol ; 428(8): 1515-30, 2016 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-26920109

RESUMEN

The ETS transcriptional repressor ETV6 (or TEL) is autoinhibited by an α-helix that sterically blocks its DNA-binding ETS domain. The inhibitory helix is marginally stable and unfolds when ETV6 binds to either specific or non-specific DNA. Using NMR spectroscopy, we show that folding of the inhibitory helix requires a buried charge-dipole interaction with helix H1 of the ETS domain. This interaction also contributes directly to autoinhibition by precluding a highly conserved dipole-enhanced hydrogen bond between the phosphodiester backbone of bound DNA and the N terminus of helix H1. To probe further the thermodynamic basis of autoinhibition, ETV6 variants were generated with amino acid substitutions introduced along the solvent exposed surface of the inhibitory helix. These changes were designed to increase the intrinsic helical propensity of the inhibitory helix without perturbing its packing interactions with the ETS domain. NMR-monitored amide hydrogen exchange measurements confirmed that the stability of the folded inhibitory helix increases progressively with added helix-promoting substitutions. This also results in progressively reinforced autoinhibition and decreased DNA-binding affinity. Surprisingly, locking the inhibitory helix onto the ETS domain by a disulfide bridge severely impairs, but does not abolish DNA binding. Weak interactions still occur via an interface displaced from the canonical ETS domain DNA-binding surface. Collectively, these studies establish a direct thermodynamic linkage between inhibitory helix stability and ETV6 autoinhibition, and demonstrate that helix unfolding does not strictly precede DNA binding. Modulating inhibitory helix stability provides a potential route for the in vivo regulation of ETV6 activity.


Asunto(s)
Proteínas Proto-Oncogénicas c-ets/química , Proteínas Proto-Oncogénicas c-ets/fisiología , Proteínas Represoras/química , Proteínas Represoras/fisiología , Amidas/química , Aminoácidos/química , Animales , ADN/química , Disulfuros/química , Hidrógeno/química , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía de Resonancia Magnética , Ratones , Unión Proteica , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Termodinámica , Proteína ETS de Variante de Translocación 6
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