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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

MH-1, a computer-operated mechanical hand

Ernst, Heinrich Arnold January 1962 (has links)
Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering, 1962. / Vita. / Includes bibliographical references (leaves 93-100). / by Heinrich Arnold Ernst. / Sc.D.
2

Crosstalk between high-risk human papillomavirus E7 and p63 in cervical cancer

Eldakhakhny, Sahar January 2018 (has links)
Introduction: Cervical cancer is the fourth most common malignancy diagnosed in women worldwide. It results from cellular transformation by the high-risk human papillomavirus (HPV) oncogenes E6 and E7, which accounts for more than 99% of diagnosed cases. HPV links its life cycle to epithelial proliferation and differentiation, which requires the cells to remain active in cell cycle. p63 modulates epithelial development as well as proliferation, differentiation and DNA damage response (DDR), which makes it an important target for HPV oncoproteins to allow viral replication and survival in infected cells. Methods: In this study, small interfering RNAs targeting E7 oncoprotein and p63 in the HPV16 positive cervical cancer cell line CaSki were used. Western blotting, proliferation assays, apoptosis assays and cell cycle analysis were applied to examine the effects of E7 and p63 depletion on cell fate. Overexpression of different types of HPV-E7 was performed in the N/Tert-1 keratinocyte cell line to study the effect of E7 overexpression on p63 level. Results: E7 drives the expression of p63 at both transcript and protein levels in cervical cancer cell lines. Downregulation of E7 is accompanied by a remarkable inhibition of cell proliferation and cell cycle arrest in the G0/G1 phase. Depletion of E7 is associated with a significant reduction in p63 expression which is not due to impaired proliferation or induced differentiation. Downregulation of p63 is associated with delayed DDR in cervical cancer cells following treatment with ionising radiation. High-risk HPV E7s are more potent in inducing p63 upregulation and increasing the proliferation rates in keratinocytes. Conclusion: This work for the first time demonstrated that E7 modulates the expression of p63, which regulates DNA damage repair pathways, that promotes efficient and rapid repair of the DNA damage following ionising radiation treatment in cervical cancer cells. Tumour recurrence due to resistance to radiotherapy is common, mostly due to promoted DNA repair ability of cancer cells to reduce radiation-induced toxicity and increase cell survival in response to ionising radiation. These findings might be the key to the development of radioresistance in cervical cancer. The HPV E7-p63 axis may be a novel therapeutic target to enhance radio-sensitivity in HPV-transformed tumours.
3

Avaliação da presença do Papilomavírus humano (HPV) em tumores de pulmão

AMARAL, Carolina Maria Medeiros Do 15 December 2015 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-04-03T14:39:58Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese - Carolina Amaral (2).pdf: 3097271 bytes, checksum: a09eebe935773ec4b3446a95c4507f5c (MD5) / Made available in DSpace on 2017-04-03T14:39:58Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese - Carolina Amaral (2).pdf: 3097271 bytes, checksum: a09eebe935773ec4b3446a95c4507f5c (MD5) Previous issue date: 2015-12-15 / FACEPE / Os Papilomavírus humano (HPV) infectam mucosas e epitélio contribuindo para o desenvolvimento de tumores benignos como também malignos. São amplamente conhecidos como causadores do câncer cervical, contudo, atualmente, vem apresentando evidências de associação com diversos outros tipos de canceres, como o câncer de pulmão. Sendo assim, o presente estudo avaliou a presença do DNA do HPV em tumores de pulmão de pacientes do Estado de Pernambuco bem como a expressão de suas oncoproteínas E6 e E7. Para isto, a detecção foi feita em amostras de tecidos de tumores frescos e parafinados de 63 pacientes. HPV estava presente em 52% das amostras, sendo detectados os tipos 16 e 18 com frequências de 81 e 19%, respectivamente. Quanto a presença do vírus nos diferentes tipos histológicos dos tumores, foi detectado HPV em 40% dos carcinomas escamosos, 33% dos adenocarcinomas, 18% dos carcinomas de células pequenas e 9% em carcinoma de células grandes. Através da técnica de imunohistoquimica detectou-se a presença das oncoproteinas virais E6 (anticorpo anti-HPV 16 e anti-HPV 18) e E7 (anticorpo anti-HPV 16 e anti-HPV 18) com frequências de 85 e 75%, respectivamente. Tal resultado confirma os resultados obtidos molecularmente quanto à presença do HPV e é sugestivo de que o vírus esteja em atividade nas células tumorais e provavelmente esteja desempenhando um papel na carcinogênese de pulmão. No entanto, mais estudos são necessários para se ter um maior esclarecimento sobre interação de E6 e E7 com proteínas celulares na tumorigenese pulmonar. / Small DNA viruses - Human Papillomavirus (HPV) - infect oral mucosa and the epthelium, which leads to the development of both benign and malign tumors. They are widely known as the principal causes of cervical cancer although currently there is evidence to show that they are associated with several other types of cancer, such as lung cancer. In the light of this, this study evaluated the presence of HPV in the tumors of lungs of patients from the State of Pernambuco, as well as the E6 and E7 oncoproteins expression. This involved carrying out the detection in tumor tissue samples that were fresh and paraffin-embedded and taken from 63 patients. HPV was found to be present in 52% of the samples, and types 16 and 18 were detected with frequencies of 81% and 19% respectively. With regard to the presence of the vírus in different histological types of tumors, HPV was detected in 40% of the squamous carcinomas, 33% of the adenocarcinomas, 18% of the small cell carcinomas and 9% in large cell carcinomas. The presence of the E6 (antibody anti-HPV 16 and anti-HPV 18) and E7 (antibody anti-HPV 16 and anti-HPV 18) oncoproteins was detected by means of the immunohistochemical technique and this confirmed the results obtained from a molecular analysis with regard to the presence of the virus and it is suggestive that the virus is active in tumor cells and is probably playing a role in lung carcinogenesis. However, further studies are required to have a clearer understanding of the interaction of E6 and E7 with the cell proteins in pulmonary tumorigenesis.
4

Characterization of the Nucleocytoplasmic Transport of the Cutaneous HPV8 E7 Protein

Onder, Zeynep January 2014 (has links)
Thesis advisor: Junona Moroianu / Some non melanoma skin cancers (NMSC) have been associated with human papillomavirus (HPV) pathogenesis, like epidermodysplasia verruciformis (EV) and squamous cell carcinoma (SCC). EV is a genetically inherited skin disease that develops when the individuals are infected with cutaneous HPV types belonging to the β-genus, especially types 5 and 8. Transgenic mouse lineages expressing all early genes of cutaneous HPV8 develop papillomas, dysplasias and SCC after UV irradiation and this correlates with enhanced HPV8 oncogenes expression. We have previously discovered that the nuclear localization of mucosal HPV16 E7 and HPV11 E7 proteins is mediated by their zinc-binding domain via a Ran-dependent pathway and independent of nuclear import receptors and that a patch of hydrophobic residues within the zinc-binding domain of HPV16 E7 and HPV11 E7 proteins is responsible for their nuclear import via hydrophobic interactions with FG nucleoporins. Here we investigated the nucleocytoplasmic traffic of cutaneous HPV8 E7 protein using confocal microscopy to analyze the intracellular localization of EGFP-8E7, its subdomains and its mutants after transient transfections. We also investigated the nuclear import ability of GST-8E7, its subdomains and mutants using in vitro nuclear import assays in digitonin-permeabilized HeLa cells. In addition, we performed isolation assays to study the direct interaction between HPV8 E7 and two FG nucleoporins, Nup62 and Nup153 or the nuclear export receptor, CRM1. We found that the nuclear import of cutaneous HPV8 E7 is mediated by a nuclear localization signal (NLS) located within its zinc-binding domain. Furthermore, we determined that the hydrophobic residues within the 65LRLFV69 patch are responsible for the nuclear import and nuclear localization of HPV8 E7 via direct hydrophobic interactions with FG nucleoporins, Nup62 and Nup153, whereas the positively charged arginine 66 plays no significant role in the function of the NLS. In addition, we examined the nuclear export mechanism of cutaneous HPV8 E7 protein and showed that it has a leucine-rich nuclear export signal (NES) in its C-terminal domain that is recognized by the CRM1 nuclear export receptor. These studies are essential for understanding the nucleocytoplasmic traffic of cutaneous HPV8 E7 protein. / Thesis (PhD) — Boston College, 2014. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Biology.
5

Studies on the Nucleocytoplasmic Transport of the E7 Oncoprotein of High-Risk HPV Type 16

Eberhard, Jeremy January 2013 (has links)
Thesis advisor: Junona Moroianu / Human papillomaviruses (HPVs) have been estimated to be the most common sexually transmitted infection in the United States. In addition to condyloma accuminata, infection of the squamous basal epithelium by high-risk HPVs, notably type 16 (HPV16), has been shown to be the primary etiological agent in the majority of cervical carcinomas. The E7 major transforming protein of HPV16, along with E6, has been linked to tumorigenesis and malignancy. While the E7 protein itself possesses no enzymatic activity, its ability to bind a number of nuclear and cytoplasmic targets subverts a variety of cellular regulatory complexes and facilitates viral replication. Previous studies in the Moroianu Lab have shown the HPV16 E7 oncoprotein to translocate across the nuclear pore complex (NPC) in a facilitated manner dependent on a non-canonical, c-terminal, nuclear localization signal (cNLS) for import, and a consensus leucine-rich nuclear export sequence (NES) for export (28). While the leucine-rich NES has been characterized, a full examination of the cNLS has yet to be performed. Here we present evidence that the karyopherin independent nuclear import mediated by the cNLS of 16E7 is dependent on its c-terminal Zn binding domain. Furthermore, we demonstrate that nuclear import is mediated by the direct interaction of a small patch of hydrophobic residues, 65LRLCV69, with the FG domain of the central FG-nucleoporin Nup62. In addition, we examined a potential regulatory mechanism of 16E7 nucleocytoplasmic translocation. Previous work has shown that a serine conserved in the high-risk HPVs at position 71 is phosphorylated by an unknown kinase. Here we present evidence that while phosphorylation of S71 is not required for either 16E7 nuclear localization or nuclear export in HeLa cells, mimicking phosphorylation of the S71 residue results in a statistically significant shift in the distribution of localization phenotypes of the resultant cell population toward a larger percentage exhibiting more nuclear localization. These data suggest that nucleocytoplasmic transport of 16E7 is, at least in part, a regulated process. / Thesis (PhD) — Boston College, 2013. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Biology.
6

Characterization of the nuclear import and export signals of the E7 protein of human papillomavirus type 11

McKee, Courtney Holmes January 2011 (has links)
Thesis advisor: Junona Moroianu / The E7 protein of low risk HPV11 has been shown to interact with multiple proteins, including pRb, in both the cytoplasm and the nucleus. High risk HPV16 E7 and low risk HPV11 E7 share a novel nuclear import pathway independent of karyopherins but dependent on the GTPase Ran (Angeline, et al., 2003; Knapp, et al., 2009; Piccioli, et al., 2010). We continued to analyze the nucleocytoplasmic transport of HPV11 E7 in vivo through transfection assays in HeLa cells with EGFP-HPV11 E7 wild type and mutant fusion constructs. We found that nuclear localization of HPV11 E7 is mediated by a nuclear localization signal located in the C-terminal domain which contains a unique zinc-binding domain. Mutations of cysteine residues that interfered with zinc-binding clearly disrupted the nuclear localization of the EGFP-11cE7 and EGFP-11E7 mutants. These data suggest that the integrity of the zinc-binding domain is essential for the nuclear localization of HPV11 E7. In addition, we discovered that HPV11 E7 has a leucine-rich C-terminal nuclear export signal (NES) (76IRQLQDLLL84) mediating the nuclear export of HPV11 E7 in a CRM1-dependent manner. / Thesis (BS) — Boston College, 2011. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Biology Honors Program. / Discipline: Biology.
7

Avaliação de possível alteração nos genes E6 e E7 do papilomavírus humano tipos 18 e 31 e sua relação com o polimorfismo do códon 72 do gene TP53 em lesões de colo de útero de pacientes da região Nordeste do Brasil

CHAGAS, Barbara Simas 31 January 2010 (has links)
Made available in DSpace on 2014-06-12T18:07:26Z (GMT). No. of bitstreams: 2 arquivo768_1.pdf: 2124568 bytes, checksum: 406686ffa8bab1f85f50c826f2d4d9f4 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O papilomavírus humano (HPV) apresenta a capacidade de provocar infecção clínica ou subclínica em mulheres e homens após a transmissão por via sexual. Estudos confirmam a relação entre a infecção com alguns tipos de HPV e a etiologia do câncer cervical, tido como a segunda maior causa de morte entre as mulheres no mundo. Os genes E6 e E7 são os principais oncogenes dos papilomavírus humanos de alto risco. Os produtos desses genes inibem a p53 e pRb, respectivamente, contribuindo para a transformação celular. Tem sido descrito um polimorfismo comum do gene supressor de tumor TP53, localizado no códon 72 do éxon 4, resultando em prolina (p53Pro) ou arginina (p53Arg). O genótipo Arg/Arg versus Arg/Pro ou Pro/Pro para o códon 72 do gene TP53 tem sido discutido como um importante fator de risco para as neoplasias cervicais. Estudos evidenciam uma diversidade de variantes de tipos de HPV. As diferenças nas sequências nucleotídicas entre os variantes HPV podem resultar em alterações nos aminoácidos codificados, podendo levar a potenciais oncogênicos distintos. Neste trabalho foi proposta a análise da variabilidade genética das regiões genômicas E6 e E7, dos HPVs 18 e 31, bem como a análise do polimorfismo do gene supressor tumoral TP53, códon 72 éxon 4, em amostras cervicais de mulheres da região metropolitana do Recife. Para a análise da variabilidade, amostras de DNA positivas para os HPVs 18 e 31 foram amplificadas, clonadas e sequenciadas quanto às regiões genômicas E6 e E7. As sequências obtidas foram alinhadas com sequência referência do GenBank para avaliar possíveis polimorfismos. A detecção do polimorfismo no gene TP53 foi realizada por meio de PCR alelo específica. Foi possível identificar alterações gênicas nas sequências de E6 e E7 dos HPVs 18 e 31 em relação à sequência de referência depositada do GenBank. Três alterações nucleotídicas em E6 de HPV-31 estão sendo descritas pela primeira vez neste estudo. Algumas alterações nucleotídicas ocasionaram mutações não sinônimas. As alterações nas amostras de HPV-31 da região metropolitana do Recife podem estar relacionadas com a diferença encontrada na distribuição do HPV-31 entre as regiões Sudeste e Nordeste do Brasil. Na análise do polimorfismo do códon 72 do gene TP53, o presente estudo mostrou frequências similares dos genótipos Arg/Arg entre casos e controles, reforçando a hipótese de que este polimorfismo não é um fator de risco para a predisposição ao desenvolvimento de lesões cervicais pré-malignas e malignas quando associado ao HPV
8

Diferenças Estruturais e \"Docking\" Receptor-Ligante da Proteína E7 do Vírus do Papiloma Humano (HPV) de Alto e Baixo Riscos para o Câncer Cervical. / Structural Differences and Receptor-Ligand Docking of E7 Protein from Human Papillomavirus (HPV) of High and Low Risk for Cervical Cancer.

Nicolau Junior, Nilson 25 March 2013 (has links)
O câncer cervical afeta milhões de mulheres em todo o mundo a cada ano. A maioria dos casos de câncer cervical é causada pelo vírus do papiloma humano (HPV) que é sexualmente transmissível. Cerca de 40 tipos de HPV infectam o colo do útero e estes são designados como sendo de alto ou de baixo risco com base no seu potencial para provocar lesões de alto grau e câncer. A oncoproteína E7 do HPV está diretamente envolvida no aparecimento de câncer de colo do útero. Esta se associada com a proteína pRb e outros alvos celulares que promovem a imortalização celular e carcinogênese. Apesar de muito progresso nos estudos sobre os HPVs de alto risco, ainda não existe uma terapêutica adequada para o tratamento das lesões e câncer causados por este vírus. Este trabalho teve como objetivo entender as diferenças estruturais entre E7 de alto e baixo risco e sugerir, através de análises de bioinformática, possíveis sítios de ligação e inibidores para a E7. Esta é a primeira descrição da modelagem e análise de dinâmica molecular de quatro estruturas tridimensionais completas da E7 dos tipos de alto risco (HPV tipos 16 e 18), de baixo risco (HPV tipo 11) e não relacionadas ao câncer cervical (HPV tipo 1A). Os modelos foram construídos por uma abordagem híbrida usando modelagem por homologia e ab initio. Os modelos foram usados em simulações de dinâmica molecular por 50 ns, sob condições normais de temperatura e pressão. A desordem intrínseca da sequência da proteína E7 foi avaliada com o uso de ferramentas in silico. Os domínios N-terminal de todas as E7 estudadas, mesmo as de alto risco, exibiram estruturas secundárias depois da modelagem. Nas análises da trajetória da dinâmica molecular, as E7s dos HPVs dos tipos 16 e 18 apresentaram maior instabilidade nos seus domínios N-terminais em relação aos do HPV dos tipos 11 e 01. No entanto, esta variação não afetou a conformação das estruturas secundárias durante a simulação. A análise com ANCHOR indicou que as regiões CR1 e CR2 regiões dos tipos de HPV 16 e 18 contêm possíveis alvos para a descoberta da droga. Já a região CR3 do domínio C-terminal indicou estabilidade nas análises in silico e, por isso, foi usada como alvo de busca de modelos farmacofóricos e docking macromolecular. A proteína usada como modelo foi a E7 do HPV tipo 45 resultante de análises de ressonância magnética nuclear (RMN) e depositada no banco de dados de proteína (ID: 2F8B). Foram selecionados por análises sequenciais de busca farmacofórica, docking e re-docking, 19 compostos (extraídos de amplas bibliotecas de pequenos ligantes) com potencial para candidatos a inibidores da E7. Eles foram avaliados quanto a sua função de pontuação, mapas de interação receptor-ligante e toxicidade e os melhores foram indicados para estudos futuros. / Cervical cancer affects millions of women around the world each year. Most cases of cervical cancer are caused by human papilloma virus (HPV) which is sexually transmitted. About 40 types of HPV infect the cervix and these are designated as being at high or low risk based on their potential to cause high-grade lesions and cancer. The E7 oncoprotein from HPV is directly involved in the onset of cervical cancer. It associates with the pRb protein and other cellular targets that promote cell immortalization and carcinogenesis. Although the progress in studies with high-risk HPVs there is still no adequate therapy for the treatment of lesions and cancers caused by this virus. This study aimed to understand the structural differences between E7 of high and low risk and suggest, with the aid of bioinformatics analyzes, possible binding sites and inhibitors for the E7. This is the first description of the modeling and molecular dynamics analysis of four complete three-dimensional structures of E7 from high-risk types (HPV types 16 and 18), low risk (HPV type 11) and that not related to cervical cancer (HPV 01). The models were constructed by a hybrid approach using homology modeling and ab initio. The models were used in molecular dynamics simulations for 50 ns, under normal temperature and pressure. The intrinsic disorder of the E7 protein sequence was assessed using in silico tools. The N-terminal domains of all E7s, even the high-risks, showed secondary structures after modeling. In the trajectory analyzes of molecular dynamics, the E7s of HPV types 16 and 18 showed high instability in their N-terminal domains than those of HPV types 11 and 01, however, this variation did not affect the conformation of secondary structures during the simulation. The analysis with ANCHOR indicated that regions CR1 and CR2 regions of types of HPV 16 and 18 contain possible targets for drug discovery. The CR3 region of the C-terminal domain indicated stability by in silico analyzes and was therefore used as target to search for pharmacophoric models and \"docking\". The protein used as a model was the E7, from HPV type 45, constructed by analysis of nuclear magnetic resonance (NMR) and deposited in the protein data bank (ID: 2F8B). It was selected 19 compounds as potential candidates for E7 inhibitors (extracted from large libraries of small ligands) using sequential pharmacophore search, docking and re-docking analyzes. They were evaluated for their scoring function, maps of receptor-ligand interactions and toxicity and the best suited were indicated for future studies.
9

Imunoterapia e imunomodulação envolvendo a glicoproteína D (gD) do HSV-1 em formulações vacinais voltadas para o controle de tumores associados ao HPV-16. / Immunotherapy and immunomodulation involving glycoprotein D (gD) of HSV-1 in vaccine formulations directed to HPV-16-associated tumors control.

Bruna Felicio Milazzotto Maldonado Porchia 25 November 2015 (has links)
O câncer cervical é considerado um grande problema de saúde pública e um dos maiores causadores de mortes relacionadas a tumores em mulheres. O principal objetivo desta tese foi aumentar a eficácia antitumoral terapêutica da proteína gDE7 por meio da associação de adjuvantes vacinais em formulações testadas em condições experimentais com a linhagem celular tumoral TC-1. A proteína gDE7 foi produzida a partir de uma linhagem de E. coli e associada a diferentes adjuvantes. A proteína gDE7 coadministrada ao poly(I:C) conferiu proteção antitumoral completa aos camundongos previamente desafiados e induziu ativação de linfócitos T CD8+ E7-específicos polifuncionais, citotóxicos e de fenótipo de memória efetora/efetor. Foi demonstrado que a proteína gDE7 ativa de forma específica a subpopulação de células dendríticas especializada na apresentação cruzada de antígenos para linfócitos T CD8+, tanto em camundongos como em seres humanos. Esses resultados abrem perspectivas para o emprego da proteína gD como plataforma vacinal para o controle de tumores induzidos pelo HPV-16. / Cervical cancer is considered a major public health problem and one of the leading causes of cancer death in women. The main goal of this thesis was the improvement of a therapeutic antitumor vaccine based on gDE7 protein in formulations admixed with adjuvants under experimental conditions with the tumor cell line TC-1. The gDE7 protein was expressed and purified from E. coli, and then tested in combination with different vaccine adjuvants. The gDE7 protein admixed with poly(I:C) conferred complete therapeutic antitumor protection to mice previously challenged with TC-1 cells and induced polyfunctional, cytotoxic E7-specific CD8+ T cells with effector/effector memory phenotype. It was also demonstrated that the gDE7 protein activated a specialized dendritic cell subset involved in specific antigen cross-presentation to CD8+ T cells, both in mice and humans. These results open perspectives for the use of the gD protein use as a vaccine platform for the control of HPV-16-induced tumors.
10

Diferenças Estruturais e \"Docking\" Receptor-Ligante da Proteína E7 do Vírus do Papiloma Humano (HPV) de Alto e Baixo Riscos para o Câncer Cervical. / Structural Differences and Receptor-Ligand Docking of E7 Protein from Human Papillomavirus (HPV) of High and Low Risk for Cervical Cancer.

Nilson Nicolau Junior 25 March 2013 (has links)
O câncer cervical afeta milhões de mulheres em todo o mundo a cada ano. A maioria dos casos de câncer cervical é causada pelo vírus do papiloma humano (HPV) que é sexualmente transmissível. Cerca de 40 tipos de HPV infectam o colo do útero e estes são designados como sendo de alto ou de baixo risco com base no seu potencial para provocar lesões de alto grau e câncer. A oncoproteína E7 do HPV está diretamente envolvida no aparecimento de câncer de colo do útero. Esta se associada com a proteína pRb e outros alvos celulares que promovem a imortalização celular e carcinogênese. Apesar de muito progresso nos estudos sobre os HPVs de alto risco, ainda não existe uma terapêutica adequada para o tratamento das lesões e câncer causados por este vírus. Este trabalho teve como objetivo entender as diferenças estruturais entre E7 de alto e baixo risco e sugerir, através de análises de bioinformática, possíveis sítios de ligação e inibidores para a E7. Esta é a primeira descrição da modelagem e análise de dinâmica molecular de quatro estruturas tridimensionais completas da E7 dos tipos de alto risco (HPV tipos 16 e 18), de baixo risco (HPV tipo 11) e não relacionadas ao câncer cervical (HPV tipo 1A). Os modelos foram construídos por uma abordagem híbrida usando modelagem por homologia e ab initio. Os modelos foram usados em simulações de dinâmica molecular por 50 ns, sob condições normais de temperatura e pressão. A desordem intrínseca da sequência da proteína E7 foi avaliada com o uso de ferramentas in silico. Os domínios N-terminal de todas as E7 estudadas, mesmo as de alto risco, exibiram estruturas secundárias depois da modelagem. Nas análises da trajetória da dinâmica molecular, as E7s dos HPVs dos tipos 16 e 18 apresentaram maior instabilidade nos seus domínios N-terminais em relação aos do HPV dos tipos 11 e 01. No entanto, esta variação não afetou a conformação das estruturas secundárias durante a simulação. A análise com ANCHOR indicou que as regiões CR1 e CR2 regiões dos tipos de HPV 16 e 18 contêm possíveis alvos para a descoberta da droga. Já a região CR3 do domínio C-terminal indicou estabilidade nas análises in silico e, por isso, foi usada como alvo de busca de modelos farmacofóricos e docking macromolecular. A proteína usada como modelo foi a E7 do HPV tipo 45 resultante de análises de ressonância magnética nuclear (RMN) e depositada no banco de dados de proteína (ID: 2F8B). Foram selecionados por análises sequenciais de busca farmacofórica, docking e re-docking, 19 compostos (extraídos de amplas bibliotecas de pequenos ligantes) com potencial para candidatos a inibidores da E7. Eles foram avaliados quanto a sua função de pontuação, mapas de interação receptor-ligante e toxicidade e os melhores foram indicados para estudos futuros. / Cervical cancer affects millions of women around the world each year. Most cases of cervical cancer are caused by human papilloma virus (HPV) which is sexually transmitted. About 40 types of HPV infect the cervix and these are designated as being at high or low risk based on their potential to cause high-grade lesions and cancer. The E7 oncoprotein from HPV is directly involved in the onset of cervical cancer. It associates with the pRb protein and other cellular targets that promote cell immortalization and carcinogenesis. Although the progress in studies with high-risk HPVs there is still no adequate therapy for the treatment of lesions and cancers caused by this virus. This study aimed to understand the structural differences between E7 of high and low risk and suggest, with the aid of bioinformatics analyzes, possible binding sites and inhibitors for the E7. This is the first description of the modeling and molecular dynamics analysis of four complete three-dimensional structures of E7 from high-risk types (HPV types 16 and 18), low risk (HPV type 11) and that not related to cervical cancer (HPV 01). The models were constructed by a hybrid approach using homology modeling and ab initio. The models were used in molecular dynamics simulations for 50 ns, under normal temperature and pressure. The intrinsic disorder of the E7 protein sequence was assessed using in silico tools. The N-terminal domains of all E7s, even the high-risks, showed secondary structures after modeling. In the trajectory analyzes of molecular dynamics, the E7s of HPV types 16 and 18 showed high instability in their N-terminal domains than those of HPV types 11 and 01, however, this variation did not affect the conformation of secondary structures during the simulation. The analysis with ANCHOR indicated that regions CR1 and CR2 regions of types of HPV 16 and 18 contain possible targets for drug discovery. The CR3 region of the C-terminal domain indicated stability by in silico analyzes and was therefore used as target to search for pharmacophoric models and \"docking\". The protein used as a model was the E7, from HPV type 45, constructed by analysis of nuclear magnetic resonance (NMR) and deposited in the protein data bank (ID: 2F8B). It was selected 19 compounds as potential candidates for E7 inhibitors (extracted from large libraries of small ligands) using sequential pharmacophore search, docking and re-docking analyzes. They were evaluated for their scoring function, maps of receptor-ligand interactions and toxicity and the best suited were indicated for future studies.

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