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2.
ACS Chem Biol ; 17(5): 1022-1029, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35467836

RESUMO

Genetic code expansion has proven invaluable to the elucidation of functions of defined protein modifications through the site-specific incorporation of noncanonical amino acids. The use of nonhydrolyzable derivatives of post-translational modifications can greatly increase site stoichiometry and half-life. Investigating acetyllysine reader domain (bromodomain) interactions with acetylated nonhistone proteins is challenging due to the limited tools available and dynamic nature of this post-translational modification. Here, we demonstrate that bromodomains bind acetyllysine peptides and those substituted with an acetyllysine derivative, trifluoroacetyllysine, with similar affinity and selectivity. Importantly, both trifluoroacetyllysine and acetyllysine can be site-specifically incorporated into proteins expressed in bacterial and mammalian cells, and the strong electron-withdrawing trifluoro substituent makes the latter resistant to deacetylation by sirtuins (SIRTs). The controlled expression of SIRT-resistant, site-specifically acetylated transcription factors expands the set of available tools for determining the function of acetylation, and it serves as a template for investigating bromodomain interactions with acetylated transcription factors.


Assuntos
Lisina , Sirtuínas , Acetilação , Animais , Lisina/química , Mamíferos/metabolismo , Ligação Proteica , Domínios Proteicos , Processamento de Proteína Pós-Traducional , Sirtuínas/metabolismo , Fatores de Transcrição/metabolismo
3.
Eye (Lond) ; 34(12): 2197-2218, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32778738

RESUMO

Congenital and childhood cataracts are uncommon but regularly seen in the clinics of most paediatric ophthalmology teams in the UK. They are often associated with profound visual loss and a large proportion have a genetic aetiology, some with significant extra-ocular comorbidities. Optimal diagnosis and treatment typically require close collaboration within multidisciplinary teams. Surgery remains the mainstay of treatment. A variety of surgical techniques, timings of intervention and options for optical correction have been advocated making management seem complex for those seeing affected children infrequently. This paper summarises the proceedings of two recent RCOphth paediatric cataract study days, provides a literature review and describes the current UK 'state of play' in the management of paediatric cataracts.


Assuntos
Extração de Catarata , Catarata , Oftalmologia , Catarata/terapia , Criança , Humanos , Reino Unido/epidemiologia , Transtornos da Visão/terapia
4.
Gen Comp Endocrinol ; 295: 113522, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32492383

RESUMO

The crustacean hyperglycemic hormone (CHH) neuropeptide family has multiple functions in the regulation of hemolymph glucose levels, molting, ion, and water balance and reproduction. In crab species, three neuroendocrine tissues: the eyestalk ganglia (medulla terminalis X-organ and -sinus gland = ES), the pericardial organ (PO), and guts synthesize a tissue-specific isoforms of CHH neuropeptides. Recently the presence of the mandibular organ-inhibiting hormone (MOIH) was reported in the stomatogastric nervous system (STNS) that regulates the rhythmic muscle movements in esophagus, cardiac sac, gastric and pyloric ports of the foregut. In this study, we aimed to determine the presence of a tissue-specific CHH isoform in the Jonah crab, Cancer borealis using PCR with degenerate primers and 5', 3' rapid amplification of cDNA ends (RACE) in the ES. PO, and STNS. The analysis of CHH sequences shows that C. borealis has one type of CHH isoform, unlike other crab species. We also isolated the cDNA sequence of molt-inhibiting hormone (MIH) in the ES and MOIH in the ES and STNS. The presence of CHH, MOIH and MIH in the sinus gland of adult females and males is confirmed by using a dot-blot assay with the putative peaks collected from RP-HPLC and anti-Cancer sera for CHH, MIH, and MOIH. The present of crustacean female sex hormone (CFSH) in the sinus gland of adult females was examined with a dot-blot assay with anti-Callinectes CFSH serum. Levels of CHH, MOIH, and MIH in the sinus gland and their expressions in the eyestalk ganglia are estimated in the adult males, where CHH is the predominant form among these neuropeptides.


Assuntos
Proteínas de Artrópodes/genética , Braquiúros/genética , Regulação da Expressão Gênica , Hormônios de Invertebrado/genética , Proteínas do Tecido Nervoso/genética , Sequência de Aminoácidos , Estruturas Animais/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Clonagem Molecular , DNA Complementar/metabolismo , Feminino , Hemolinfa/metabolismo , Masculino , Neuropeptídeos/química , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Sistemas Neurossecretores/metabolismo
5.
Transl Psychiatry ; 10(1): 14, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-32066689

RESUMO

Later sleep timing, circadian preference, and circadian rhythm timing predict worse outcomes across multiple domains, including mood disorders, substance use, impulse control, and cognitive function. Disturbed sleep is common among pregnant and postpartum women. We examined whether sleep timing during third trimester of pregnancy predicted postpartum symptoms of mania, depression, and obsessive-compulsive disorder (OCD). Fifty-one women with a previous, but not active, episode of unipolar or bipolar depression had symptoms evaluated and sleep recorded with wrist actigraphy at 33 weeks of gestation and 2, 6, and 16 weeks postpartum. Circadian phase was measured in a subset of women using salivary dim light melatonin onset (DLMO). We divided the sample into "early sleep" and "late sleep" groups using average sleep onset time at 33 weeks of gestation, defined by the median-split time of 11:27 p.m. The "late sleep" group reported significantly more manic and depressive symptoms at postpartum week 2. Longer phase angle between DLMO and sleep onset at 33 weeks was associated with more manic symptoms at postpartum week 2 and more obsessive-compulsive symptoms at week 6. Delayed sleep timing in this sample of at-risk women was associated with more symptoms of mania, depression, and OCD in the postpartum period. Sleep timing may be a modifiable risk factor for postpartum depression.


Assuntos
Depressão Pós-Parto , Melatonina , Actigrafia , Ritmo Circadiano , Depressão Pós-Parto/diagnóstico , Feminino , Humanos , Gravidez , Sono
6.
J Intellect Disabil Res ; 64(3): 234-245, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31975473

RESUMO

BACKGROUND: A new legal capacity act was introduced in Ireland in 2015. This study aimed to identify and critically examine key issues in the area of decision-making capacity from the perspective of psychologists working with adults with an intellectual disability. METHODS: A qualitative exploratory approach was employed, and the study was positioned in a social constructionist framework. Purposive and snowballing sampling methods were used to recruit 15 clinical psychologists working with adults with an intellectual disability. Data were collected with the use of individual semistructured interviews. Interview transcripts were analysed using a model of thematic analysis. RESULTS: Six themes were identified: (1) a presumption of capacity but a culture of incapacity, (2) supporting decision making as a process, (3) authenticity of decision making, (4) need for support and training, (5) contributions of psychology and (6) the way forward. CONCLUSIONS: Participants described that people with intellectual disabilities were often excluded from decision-making processes. They welcomed the functional approach to decision making, considered substituted decision making to be necessary within a support framework and described supporting decision making as a process. Systemic, resource and attitudinal challenges were identified.


Assuntos
Atitude do Pessoal de Saúde , Tomada de Decisões , Deficiência Intelectual , Competência Mental , Pessoas com Deficiência Mental , Relações Profissional-Paciente , Adulto , Humanos , Irlanda , Competência Mental/legislação & jurisprudência , Pessoas com Deficiência Mental/legislação & jurisprudência , Psicologia , Pesquisa Qualitativa
7.
J Hosp Infect ; 103(4): 428-434, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31394145

RESUMO

BACKGROUND: Infections account for 15% of neonatal deaths and one-tenth of maternal mortality globally. Evidence-based practices to prevent and control infection are essential to reduce newborn and maternal mortality. AIM: To identify the barriers and opportunities experienced by staff when implementing infection prevention and control (IPC) guidelines in maternity wards and delivery units in six health centres in two states in Nigeria. METHODS: A structured survey was undertaken in the maternity ward and delivery unit of six healthcare facilities to assess critical infrastructure and equipment. A survey was completed with the matron to assess staff practices and quality assurance procedures. Data were triangulated with qualitative data from interviews with facility staff. FINDINGS: Usable handwashing facilities - with water, functioning taps and soap available - were present in the delivery units of all six facilities, but were present in only one postnatal ward. All facilities were visibly clean, and staff demonstrated a strong will to comply with protocol. Areas of concern included effectiveness of training, inadequate availability of personal protective equipment, inadequate hand hygiene practices, and outdated procedures to reprocess re-usable medical equipment. CONCLUSION: Safe childbirth and postnatal care require comprehensive adherence to hand hygiene protocols and the use of disposable personal protective equipment. Financial, equipment and human resource constraints are obstacles to effective implementation of IPC in labour and delivery wards in the centres included in this study. Recommended interim measures include the introduction of champions to systematize step-down training and to monitor and provide feedback at facility level.


Assuntos
Infecção Hospitalar/prevenção & controle , Parto Obstétrico , Fidelidade a Diretrizes/estatística & dados numéricos , Higiene das Mãos/métodos , Maternidades , Controle de Infecções/métodos , Utilização de Procedimentos e Técnicas/estatística & dados numéricos , Animais , Feminino , Humanos , Recém-Nascido , Nigéria , Gravidez , Inquéritos e Questionários
8.
J Med Chem ; 61(20): 9301-9315, 2018 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-30289257

RESUMO

The biological functions of the dual bromodomains of human transcription-initiation-factor TFIID subunit 1 (TAF1(1,2)) remain unknown, although TAF1 has been identified as a potential target for oncology research. Here, we describe the discovery of a potent and selective in vitro tool compound for TAF1(2), starting from a previously reported lead. A cocrystal structure of lead compound 2 bound to TAF1(2) enabled structure-based design and structure-activity-relationship studies that ultimately led to our in vitro tool compound, 27 (GNE-371). Compound 27 binds TAF1(2) with an IC50 of 10 nM while maintaining excellent selectivity over other bromodomain-family members. Compound 27 is also active in a cellular-TAF1(2) target-engagement assay (IC50 = 38 nM) and exhibits antiproliferative synergy with the BET inhibitor JQ1, suggesting engagement of endogenous TAF1 by 27 and further supporting the use of 27 in mechanistic and target-validation studies.


Assuntos
Benzimidazóis/metabolismo , Desenho de Fármacos , Sondas Moleculares/metabolismo , Fator de Transcrição TFIID/química , Fator de Transcrição TFIID/metabolismo , Humanos , Modelos Moleculares , Conformação Proteica , Domínios Proteicos
9.
Cell Rep ; 24(7): 1722-1729, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-30110629

RESUMO

Acetylation of histone H3 at lysine 27 is a well-defined marker of enhancer activity. However, the functional impact of this modification at enhancers is poorly understood. Here, we use a chemical genetics approach to acutely block the function of the cAMP response element binding protein (CREB) binding protein (CBP)/P300 bromodomain in models of hematological malignancies and describe a consequent loss of H3K27Ac specifically from enhancers, despite the continued presence of CBP/P300 at chromatin. Using this approach to dissect the role of H3K27Ac at enhancers, we identify a critical role for this modification in the production of enhancer RNAs and transcription of enhancer-regulated gene networks.


Assuntos
Elementos Facilitadores Genéticos , Histonas/metabolismo , Processamento de Proteína Pós-Traducional , RNA Neoplásico/genética , Fatores de Transcrição de p300-CBP/genética , Acetilação , Sítios de Ligação , Linhagem Celular Tumoral , Cromatina/química , Cromatina/metabolismo , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/metabolismo , Histonas/genética , Humanos , Lisina/metabolismo , Ligação Proteica , Domínios Proteicos , RNA Neoplásico/metabolismo , Transcrição Gênica , Fatores de Transcrição de p300-CBP/metabolismo
10.
Dis Esophagus ; 31(6)2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29800270

RESUMO

Thoracic epidural (TE) analgesia has been the standard of care for transthoracic esophagectomy patients since the 1990s. Multimodal anesthesia using intrathecal diamorphine, local anesthetic infusion catheters (LAC) into the paravertebral space and rectus sheaths and intravenous opioid postoperatively represent an alternative option for postoperative analgesia. While TE can provide excellent pain control, it may inhibit early postoperative recovery by causing hypotension and reducing mobilization. The aim of this study is to determine whether multimodal analgesia with LAC was effective with respect to adequate pain management, and compare its impact on hypotension and mobility. Patients receiving multimodal LAC analgesia were matched using propensity score matching to patients undergoing two-phase trans-thoracic esophagectomy with a TE over a two-year period (from January 2015 to December 2016). Postoperative endpoints that had been evaluated prospectively, including pain scores on movement and at rest, inotrope or vasoconstrictor requirements, and hypotension (systolic BP < 90 mmHg), were compared between cohorts. Out of 14 patients (13 male) that received LAC were matched to a cohort of 14 patients on age, sex, and comorbidity. Mean and maximum pain scores at rest and movement on postoperative days 0 to 3 were equivalent between the groups. In both cohorts, 50% of patients had a pain score of more than 7 on at least one occasion. Fewer patients in the LAC group required vasoconstrictor infusion (LAC: 36% vs. TE: 57%, P = 0.256) to maintain blood pressure or had episodes of hypotension (LAC: 43% vs. TE: 79%, P = 0.05). The LAC group was more able to ambulate on the first postoperative day (LAC: 64% vs. TE: 43%, P = 0.14) but these differences were not statistically significant. Within the epidural cohort, three patients had interruption of epidural due to dislodgement or failure of block compared to no disruption in the multimodal local anesthesia catheters group (P = 0.05). Therefore, multimodal anesthesia using spinal diamorphine with combined paravertebral and rectus sheath local anesthetic catheters appears to provide comparable pain relief post two-phase esophagectomy and may provide more reliable and safe analgesia than the current standard of care.


Assuntos
Analgesia Epidural/métodos , Analgesia/métodos , Analgésicos Opioides/administração & dosagem , Esofagectomia/efeitos adversos , Heroína/administração & dosagem , Dor Pós-Operatória/tratamento farmacológico , Toracotomia/efeitos adversos , Idoso , Analgesia/instrumentação , Catéteres , Esofagectomia/métodos , Esofagectomia/reabilitação , Feminino , Humanos , Injeções Espinhais , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/etiologia , Estudos Retrospectivos , Toracotomia/métodos , Toracotomia/reabilitação , Resultado do Tratamento
11.
Nat Commun ; 8(1): 862, 2017 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-29021563

RESUMO

Members of the ISWI family of chromatin remodelers mobilize nucleosomes to control DNA accessibility and, in some cases, are required for recovery from DNA damage. However, it remains poorly understood how the non-catalytic ISWI subunits BAZ1A and BAZ1B might contact chromatin to direct the ATPase SMARCA5. Here, we find that the plant homeodomain of BAZ1A, but not that of BAZ1B, has the unusual function of binding DNA. Furthermore, the BAZ1A bromodomain has a non-canonical gatekeeper residue and binds relatively weakly to acetylated histone peptides. Using CRISPR-Cas9-mediated genome editing we find that BAZ1A and BAZ1B each recruit SMARCA5 to sites of damaged chromatin and promote survival. Genetic engineering of structure-designed bromodomain and plant homeodomain mutants reveals that reader modules of BAZ1A and BAZ1B, even when non-standard, are critical for DNA damage recovery in part by regulating ISWI factors loading at DNA lesions and supporting transcriptional programs required for survival.ISWI chromatin remodelers regulate DNA accessibility and have been implicated in DNA damage repair. Here, the authors uncover functions, in response to DNA damage, for the bromodomain of the ISWI subunit BAZ1B and for the non-canonical PHD and bromodomain modules of the paralog BAZ1A.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Dano ao DNA , Fatores de Transcrição/fisiologia , Sistemas CRISPR-Cas , Linhagem Celular , Cromatina/metabolismo , DNA/metabolismo , Edição de Genes , Humanos , Estrutura Molecular , Fatores de Transcrição/química
12.
Diabet Med ; 34(12): 1765-1772, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28856721

RESUMO

AIMS: To determine key worries about hypoglycaemia among insulin-using adults with Type 2 diabetes using a focus group approach. METHODS: Thirteen focus groups were conducted in three diabetes outpatient care units and one peer support group was set up, in Germany. A total of 64 insulin-dependent adults with Type 2 diabetes (36.5% women, mean age 65.2 ± 11.0 years) discussed their worries about hypoglycaemia. The qualitative results were assigned into thematic categories using a bottom-up coding procedure. Participants completed the Hypoglycaemia Fear Survey and demographic measures were recorded. The results of the Hypoglycaemia Fear Survey were contrasted with the focus group findings to evaluate how accurately the Hypoglycaemia Fear Survey comprehensively captures features of fear of hypoglycaemia in Type 2 diabetes. RESULTS: Eight themes were identified: 'unconsciousness/death'; 'aloneness/ helplessness', 'fear of hurting somebody'; 'shame'; 'loss of physical control'; 'long-term complications'; 'diabetes self-management issues'; and 'impaired awareness'. A total of 30 participants (46.9%) scored ≥3 on at least one item of the Hypoglycaemia Fear Survey worry subscale, indicating elevated worries. The Hypoglycaemia Fear Survey comprehensively captured all identified themes. Self-efficacy with regard to diabetes self-management seemed to play an important role in fear of hypoglycaemia in Type 2 diabetes. CONCLUSIONS: Given that even subclinical worries can have negative effects on quality of life and diabetes self-management, emphasis should be placed on diabetes education; in particular, to help patients to develop self-efficacy concerning diabetes self-management. The Hypoglycaemia Fear Survey comprehensively captures hypoglycaemia worries in Type 2 diabetes. Additional assessment of self-efficacy might be beneficial to identify people at risk of developing hypoglycaemia worries.


Assuntos
Diabetes Mellitus Tipo 2/psicologia , Medo/psicologia , Hipoglicemia/psicologia , Adulto , Idoso , Conscientização , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Grupos Focais , Alemanha/epidemiologia , Humanos , Hipoglicemia/epidemiologia , Hipoglicemia/etiologia , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Autoeficácia , Fatores Socioeconômicos
13.
ACS Med Chem Lett ; 8(7): 737-741, 2017 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-28740608

RESUMO

The biological function of bromodomains, epigenetic readers of acetylated lysine residues, remains largely unknown. Herein we report our efforts to discover a potent and selective inhibitor of the bromodomain of cat eye syndrome chromosome region candidate 2 (CECR2). Screening of our internal medicinal chemistry collection led to the identification of a pyrrolopyridone chemical lead, and subsequent structure-based drug design led to a potent and selective CECR2 bromodomain inhibitor (GNE-886) suitable for use as an in vitro tool compound.

14.
Biochemistry ; 56(30): 4015-4027, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28692281

RESUMO

Mycobacterium tuberculosis protein Rv0577 is a prominent antigen in tuberculosis patients, the component responsible for neutral red staining of virulent strains of M. tuberculosis, a putative component in a methylglyoxal detoxification pathway, and an agonist of toll-like receptor 2. It also has an amino acid sequence that is 36% identical to that of Streptomyces coelicolor AfsK-binding protein A (KbpA), a component in the complex secondary metabolite pathways in the Streptomyces genus. To gain insight into the biological function of Rv0577 and the family of KpbA kinase regulators, the crystal structure for Rv0577 was determined to a resolution of 1.75 Å, binding properties with neutral red and deoxyadenosine were surveyed, backbone dynamics were measured, and thermal stability was assayed by circular dichroism spectroscopy. The protein is composed of four approximate repeats with a ßαßßß topology arranged radially in consecutive pairs to form two continuous eight-strand ß-sheets capped on both ends with an α-helix. The two ß-sheets intersect in the center at roughly a right angle and form two asymmetric deep "saddles" that may serve to bind ligands. Nuclear magnetic resonance chemical shift perturbation experiments show that neutral red and deoxyadenosine bind to Rv0577. Binding to deoxyadenosine is weaker with an estimated dissociation constants of 4.1 ± 0.3 mM for saddle 1. Heteronuclear steady-state {1H}-15N nuclear Overhauser effect, T1, and T2 values were generally uniform throughout the sequence with only a few modest pockets of differences. Circular dichroism spectroscopy characterization of the thermal stability of Rv0577 indicated irreversible unfolding upon heating with an estimated melting temperature of 56 °C.


Assuntos
Proteínas de Bactérias/metabolismo , Desoxiadenosinas/metabolismo , Modelos Moleculares , Mycobacterium tuberculosis/metabolismo , Vermelho Neutro/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sítios de Ligação , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Dicroísmo Circular , Cristalografia por Raios X , Desoxiadenosinas/química , Temperatura Alta/efeitos adversos , Peptídeos e Proteínas de Sinalização Intracelular , Cinética , Ligantes , Conformação Molecular , Vermelho Neutro/química , Isótopos de Nitrogênio , Ressonância Magnética Nuclear Biomolecular , Conformação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Estabilidade Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Streptomyces coelicolor/metabolismo , Homologia Estrutural de Proteína
15.
Bioorg Med Chem Lett ; 27(15): 3534-3541, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28606761

RESUMO

Bromodomain-containing protein 9 (BRD9), an epigenetic "reader" of acetylated lysines on post-translationally modified histone proteins, is upregulated in multiple cancer cell lines. To assess the functional role of BRD9 in cancer cell lines, we identified a small-molecule inhibitor of the BRD9 bromodomain. Starting from a pyrrolopyridone lead, we used structure-based drug design to identify a potent and highly selective in vitro tool compound 11, (GNE-375). While this compound showed minimal effects in cell viability or gene expression assays, it showed remarkable potency in preventing the emergence of a drug tolerant population in EGFR mutant PC9 cells treated with EGFR inhibitors. Such tolerance has been linked to an altered epigenetic state, and 11 decreased BRD9 binding to chromatin, and this was associated with decreased expression of ALDH1A1, a gene previously shown to be important in drug tolerance. BRD9 inhibitors may therefore show utility in preventing epigenetically-defined drug resistance.


Assuntos
Resistência a Medicamentos/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Aldeído Desidrogenase/genética , Família Aldeído Desidrogenase 1 , Linhagem Celular Tumoral , Desenho de Fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Piridonas/química , Piridonas/farmacologia , Retinal Desidrogenase , Fatores de Transcrição/metabolismo
16.
J Med Chem ; 59(11): 5391-402, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-27219867

RESUMO

The biological role played by non-BET bromodomains remains poorly understood, and it is therefore imperative to identify potent and highly selective inhibitors to effectively explore the biology of individual bromodomain proteins. A ligand-efficient nonselective bromodomain inhibitor was identified from a 6-methyl pyrrolopyridone fragment. Small hydrophobic substituents replacing the N-methyl group were designed directing toward the conserved bromodomain water pocket, and two distinct binding conformations were then observed. The substituents either directly displaced and rearranged the conserved solvent network, as in BRD4(1) and TAF1(2), or induced a narrow hydrophobic channel adjacent to the lipophilic shelf, as in BRD9 and CECR2. The preference of distinct substituents for individual bromodomains provided selectivity handles useful for future lead optimization efforts for selective BRD9, CECR2, and TAF1(2) inhibitors.


Assuntos
Histona Acetiltransferases/antagonistas & inibidores , Proteínas Nucleares/antagonistas & inibidores , Piridonas/farmacologia , Pirróis/farmacologia , Fatores Associados à Proteína de Ligação a TATA/antagonistas & inibidores , Fator de Transcrição TFIID/antagonistas & inibidores , Fatores de Transcrição/antagonistas & inibidores , Água/química , Sítios de Ligação/efeitos dos fármacos , Proteínas de Ciclo Celular , Relação Dose-Resposta a Droga , Transferência Ressonante de Energia de Fluorescência , Fluorometria , Histona Acetiltransferases/metabolismo , Humanos , Ligantes , Modelos Moleculares , Conformação Molecular , Proteínas Nucleares/metabolismo , Piridonas/síntese química , Piridonas/química , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade , Fatores Associados à Proteína de Ligação a TATA/metabolismo , Fator de Transcrição TFIID/metabolismo , Fatores de Transcrição/metabolismo
17.
Nat Chem Biol ; 12(7): 531-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27214401

RESUMO

The KDM5 family of histone demethylases catalyzes the demethylation of histone H3 on lysine 4 (H3K4) and is required for the survival of drug-tolerant persister cancer cells (DTPs). Here we report the discovery and characterization of the specific KDM5 inhibitor CPI-455. The crystal structure of KDM5A revealed the mechanism of inhibition of CPI-455 as well as the topological arrangements of protein domains that influence substrate binding. CPI-455 mediated KDM5 inhibition, elevated global levels of H3K4 trimethylation (H3K4me3) and decreased the number of DTPs in multiple cancer cell line models treated with standard chemotherapy or targeted agents. These findings show that pretreatment of cancer cells with a KDM5-specific inhibitor results in the ablation of a subpopulation of cancer cells that can serve as the founders for therapeutic relapse.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Proteína 2 de Ligação ao Retinoblastoma/antagonistas & inibidores , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/química , Humanos , Modelos Moleculares , Estrutura Molecular , Proteína 2 de Ligação ao Retinoblastoma/metabolismo , Relação Estrutura-Atividade
18.
ACS Med Chem Lett ; 7(5): 531-6, 2016 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-27190605

RESUMO

CBP and EP300 are highly homologous, bromodomain-containing transcription coactivators involved in numerous cellular pathways relevant to oncology. As part of our effort to explore the potential therapeutic implications of selectively targeting bromodomains, we set out to identify a CBP/EP300 bromodomain inhibitor that was potent both in vitro and in cellular target engagement assays and was selective over the other members of the bromodomain family. Reported here is a series of cell-potent and selective probes of the CBP/EP300 bromodomains, derived from the fragment screening hit 4-methyl-1,3,4,5-tetrahydro-2H-benzo[b][1,4]diazepin-2-one.

19.
Structure ; 23(10): 1801-1814, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26365797

RESUMO

Bromodomains are epigenetic readers that are recruited to acetyllysine residues in histone tails. Recent studies have identified non-acetyl acyllysine modifications, raising the possibility that these might be read by bromodomains. Profiling the nearly complete human bromodomain family revealed that while most human bromodomains bind only the shorter acetyl and propionyl marks, the bromodomains of BRD9, CECR2, and the second bromodomain of TAF1 also recognize the longer butyryl mark. In addition, the TAF1 second bromodomain is capable of binding crotonyl marks. None of the human bromodomains tested binds succinyl marks. We characterized structurally and biochemically the binding to different acyl groups, identifying bromodomain residues and structural attributes that contribute to specificity. These studies demonstrate a surprising degree of plasticity in some human bromodomains but no single factor controlling specificity across the family. The identification of candidate butyryl- and crotonyllysine readers supports the idea that these marks could have specific physiological functions.


Assuntos
Histona Acetiltransferases/química , Histonas/química , Lisina/química , Processamento de Proteína Pós-Traducional , Fatores Associados à Proteína de Ligação a TATA/química , Fator de Transcrição TFIID/química , Fatores de Transcrição/química , Acilação , Sítios de Ligação , Butiratos/química , Butiratos/metabolismo , Crotonatos/química , Crotonatos/metabolismo , Cristalografia por Raios X , Epigênese Genética , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Cinética , Lisina/metabolismo , Modelos Moleculares , Análise Serial de Proteínas , Ligação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Fatores Associados à Proteína de Ligação a TATA/genética , Fatores Associados à Proteína de Ligação a TATA/metabolismo , Fator de Transcrição TFIID/genética , Fator de Transcrição TFIID/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Água/química , Água/metabolismo
20.
Br J Dermatol ; 172(4): 933-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25124732

RESUMO

BACKGROUND: Chronic plaque psoriasis can be subdivided into two groups according to the age of onset: type 1 (early onset, before 40 years) and type 2 (late onset, at or beyond 40 years). So far, 36 genetic loci have been associated with early-onset psoriasis in genome-wide association studies of white populations, while few studies have investigated genetic susceptibility to late-onset psoriasis. OBJECTIVES: To characterize the genetics underpinning late-onset psoriasis. METHODS: We genotyped 543 cases of late-onset psoriasis and 4373 healthy controls using the Immunochip array, a dense genotyping chip containing single-nucleotide polymorphisms previously associated with autoimmune diseases. Imputation using SNP2HLA and stepwise logistic regression analysis was performed for markers spanning the human leucocyte antigen gene region. RESULTS: Two loci (HLA-C and IL12B) previously associated with early-onset psoriasis showed significant association at a genome-wide threshold in the current study (P < 5 × 10(-8)). Six more loci (TRAF3IP2, IL23R, RNF114, IFIH1, IL23A and HLA-A) showed study-wide significant association (P < 2·3 × 10(-5); calculated using Genetic type 1 error calculator). Additionally, we identified an association at IL1R1 on chromosome 2q13, which is not associated with early-onset disease. CONCLUSIONS: This is the largest study to date of genetic loci in late-onset psoriasis, and demonstrates the overlap that exists with early-onset psoriasis. It also suggests that some loci are associated exclusively with late-onset psoriasis.


Assuntos
Loci Gênicos/genética , Psoríase/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Loci Gênicos/imunologia , Predisposição Genética para Doença/genética , Genótipo , Humanos , Transtornos de Início Tardio/genética , Transtornos de Início Tardio/imunologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Psoríase/imunologia
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