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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

Hormonal control and pharmacology of bTREK-1 K+ channels in bovine adrenal zona fasciculata cells

Liu, Haiyan 09 September 2009 (has links)
No description available.
2

Estudos de variação genômica em homens azoospérmicos e sua correlação com a expressão de microRNAs em tecido testicular / Genomic Variation studies of azoospermic men and their correlation with microRNA expression in testicular tissue

Dias, Camila Calixto Moreira 22 February 2017 (has links)
A infertilidade é um problema de saúde pública com um significativo impacto social, econômico e psicológico. Em todo o mundo, a incidência da infertilidade entre a população geral é estimada em 10-15%. Cerca de 50% da infertilidade dos casais são de origem masculina. Em mais da metade dos homens inférteis, a causa da infertilidade é desconhecida (idiopática). Etiologicamente, a infertilidade masculina apresenta causas genéticas e não genéticas. Dentre as causas genéticas mais conhecidas temos mutação do receptor de andrógenos, mutação do gene regulador da condutibilidade transmembrana da fibrose cística (CFTR), anomalias cromossômicas clássicas, anomalias meióticas, microdeleções do cromossomo Y, etc. As anomalias cromossômicas são encontradas com muito mais frequência em homens inférteis, com uma incidência de 4-16% em relação à incidência de 0,4% na população fértil. Estudos mostram que as CNVs também podem estar relacionadas com a infertilidade masculina, especificamente com a falha na espermatogênese. CNVs encontradas tanto no cromossomo Y quanto nos cromossomos autossômicos também foram associadas a possíveis falhas na espermatogênese. Um outro fator que também pode estar envolvido com a infertilidade masculina é a expressão desregulada dos miRNAs. O presente trabalho teve como objetivo promover a análise em larga escala da distribuição de CNVs e do perfil transcricional dos miRNAs em amostras de biopsias testiculares de paciente com azoospermia. Para o estudo das CNVs nós utilizamos a metodologia do CytoScan HDTM da Affymetrix. O perfil transcricional de miRNAs nos indivíduos estudados foi avaliado por meio da tecnologia de microarranjos também da plataforma Affymetrix. Para estas analises montamos dois grupos de estudo (Parada de Maturação (MA) de Células Germinativas e Síndrome de Células Sertoli Only (SCOS)) e um grupo controle (azoospermia obstrutiva e espermatogênese normal). Através das análises das CNVs nós encontramos 94 CNVs nos cromossomos autossômicos e sexuais, 35 (37%) CNVs foram classificadas como benignas, 24 (23%) como potencialmente benignas, sete CNVs (7,4%) como patogênicas e sete foram classificadas como potencialmente patogênica. Todas as CNVs classificadas como patogênica estão presentes no cromossomo Y, cinco CNVs são do tipo duplicação e duas do tipo deleção. A CNV do tipo duplicação foi encontrada no paciente MA e a CNV do tipo deleção foi encontrada no paciente SCOS. As CNVs se sobrepõem e quando analisadas em conjunto (formando uma única CNV de cada condição) elas apresentam um tamanho parecido. Estas CNVs apresentam genes envolvidos na espermatogênese. As CNVs classificadas como potencialmente patogênicas estavam presentes nos cromossomos autossômicos e cromossomo X. Nestas CNVs estavam presentes genes que foram associados com a falha na espermatogênese. A análise da expressão dos miRNAs revelou um perfil transicional muito mais alterado nos pacientes com SCOS. As duas condições apresentaram miRNAs exclusivos, mas também compartilharam: 30 miRNAs. Nós identificamos duas famílias de miRNAs (miR449 e miR34) diferencialmente expressos nas duas condições e que apresentam expressão preferencial no testículo. Nossos resultados mostram que alterações no número de copias (CNVs) no cromossomo Y levam a infertilidade masculina e CNVs nos cromossomos autossômicos e X podem levar a infertilidade masculina. As alterações do tipo deleção podem levar a uma falha na espermatogênese maior que as alterações do tipo duplicação. A expressão diferencial dos miRNAs em tecido testicular de pacientes com diferenças histopatológicas (SCOS e MA) apresentam um padrão de expressão de miRNAs diferentes devido ao tipo de células germinativas que eles apresentam no tecido epitelial do testículo. / Infertility is a public health problem with significant social, economic and psychological impact. Worldwide, the incidence of infertility in the general population is estimated at 10- 15%. Approximately 50% of infertility of couples is of male origin. In more than half of infertile men, the cause of infertility is unknown (idiopathic). Etiologically, male infertility has genetic and non-genetic causes. Among the best known genetic causes we found the mutation of the androgen receptor, the cystic fibrosis transmembrane conductance regulator (CFTR), classic chromosomal abnormalities, meiotic abnormalities and microdeletions of the Y chromosome. Chromosomal abnormalities are found much more frequently in infertile men, with an incidence of 4-16% in the incidence of 0.4% in the fertile population. Studies show that CNVs can also be related to male infertility, specifically in the failure of spermatogenesis. CNVs found in both the Y and autosomes chromosomes were also associated with possible failures in spermatogenesis. Another factor that may also be involved in male infertility is the deregulated expression of miRNAs. This work aimed to promote the analysis of large-scale distribution of CNVs and the transcriptional profile of miRNAs in testicular biopsy samples from patients with azoospermia. For the study of CNV we used the CytoScan HDTM Affymetrix methodology and the transcriptional profile of miRNAs in the samples was assessed by means of microarray technology from Affymetrix platform. For these analyzes we set up two study groups (Stop Maturation (MA) of Germ Cells and Sertoli Cell Only Syndrome (SCOS)) and compared them to a control group (obstructive azoospermia, normal spermatogenesis). Through analysis of CNVs, we found 94 CNVs in sexual and autosomes chromosomes, 35 (37%) were classified as benign CNVs, 24 (23%) as a potentially benign seven CNVs (7.4%) as pathogenic and 7 were classified as potentially pathogenic. All CNVs classified as pathogenic are present on the Y chromosome, five CNVs are of duplication type and two are deletion type. The duplication type CNV was found in MA patients and deletion type CNV was found in SCOS patient. We identified that CNVs overlap and when analyzed jointed - as a single CNV of each condition - they have a similar size. These CNVs have genes involved in spermatogenesis. CNVs classified as potentially pathogenic were present in autosomes and in the X chromosome. In these CNVs were present genes that were associated with failure in spermatogenesis. The analysis of the expression of miRNAs revealed a transitional profile much more altered in patients with SCOS. The two conditions presented exclusive miRNAs, but shared 30 miRNAs differentially expressed when compared to the control group. We identify two families of miRNAs (miR449 and miR34) which exhibit preferential expression in testis as differentially expressed in both conditions. Our results show that changes in the number of copies (CNVs) on the Y chromosome lead to male infertility and CNVs in autosomes and X chromosomes may lead to male infertility. The deletion type changes can lead to a failure of spermatogenesis greater than the duplication type changes. The differential expression of miRNAs in patients with testicular tissue histopathologic differences (SCOS and MA) has a different pattern of miRNA expression due to the type of germ cells they present in epithelial tissue of the testis.
3

Estudos de variação genômica em homens azoospérmicos e sua correlação com a expressão de microRNAs em tecido testicular / Genomic Variation studies of azoospermic men and their correlation with microRNA expression in testicular tissue

Camila Calixto Moreira Dias 22 February 2017 (has links)
A infertilidade é um problema de saúde pública com um significativo impacto social, econômico e psicológico. Em todo o mundo, a incidência da infertilidade entre a população geral é estimada em 10-15%. Cerca de 50% da infertilidade dos casais são de origem masculina. Em mais da metade dos homens inférteis, a causa da infertilidade é desconhecida (idiopática). Etiologicamente, a infertilidade masculina apresenta causas genéticas e não genéticas. Dentre as causas genéticas mais conhecidas temos mutação do receptor de andrógenos, mutação do gene regulador da condutibilidade transmembrana da fibrose cística (CFTR), anomalias cromossômicas clássicas, anomalias meióticas, microdeleções do cromossomo Y, etc. As anomalias cromossômicas são encontradas com muito mais frequência em homens inférteis, com uma incidência de 4-16% em relação à incidência de 0,4% na população fértil. Estudos mostram que as CNVs também podem estar relacionadas com a infertilidade masculina, especificamente com a falha na espermatogênese. CNVs encontradas tanto no cromossomo Y quanto nos cromossomos autossômicos também foram associadas a possíveis falhas na espermatogênese. Um outro fator que também pode estar envolvido com a infertilidade masculina é a expressão desregulada dos miRNAs. O presente trabalho teve como objetivo promover a análise em larga escala da distribuição de CNVs e do perfil transcricional dos miRNAs em amostras de biopsias testiculares de paciente com azoospermia. Para o estudo das CNVs nós utilizamos a metodologia do CytoScan HDTM da Affymetrix. O perfil transcricional de miRNAs nos indivíduos estudados foi avaliado por meio da tecnologia de microarranjos também da plataforma Affymetrix. Para estas analises montamos dois grupos de estudo (Parada de Maturação (MA) de Células Germinativas e Síndrome de Células Sertoli Only (SCOS)) e um grupo controle (azoospermia obstrutiva e espermatogênese normal). Através das análises das CNVs nós encontramos 94 CNVs nos cromossomos autossômicos e sexuais, 35 (37%) CNVs foram classificadas como benignas, 24 (23%) como potencialmente benignas, sete CNVs (7,4%) como patogênicas e sete foram classificadas como potencialmente patogênica. Todas as CNVs classificadas como patogênica estão presentes no cromossomo Y, cinco CNVs são do tipo duplicação e duas do tipo deleção. A CNV do tipo duplicação foi encontrada no paciente MA e a CNV do tipo deleção foi encontrada no paciente SCOS. As CNVs se sobrepõem e quando analisadas em conjunto (formando uma única CNV de cada condição) elas apresentam um tamanho parecido. Estas CNVs apresentam genes envolvidos na espermatogênese. As CNVs classificadas como potencialmente patogênicas estavam presentes nos cromossomos autossômicos e cromossomo X. Nestas CNVs estavam presentes genes que foram associados com a falha na espermatogênese. A análise da expressão dos miRNAs revelou um perfil transicional muito mais alterado nos pacientes com SCOS. As duas condições apresentaram miRNAs exclusivos, mas também compartilharam: 30 miRNAs. Nós identificamos duas famílias de miRNAs (miR449 e miR34) diferencialmente expressos nas duas condições e que apresentam expressão preferencial no testículo. Nossos resultados mostram que alterações no número de copias (CNVs) no cromossomo Y levam a infertilidade masculina e CNVs nos cromossomos autossômicos e X podem levar a infertilidade masculina. As alterações do tipo deleção podem levar a uma falha na espermatogênese maior que as alterações do tipo duplicação. A expressão diferencial dos miRNAs em tecido testicular de pacientes com diferenças histopatológicas (SCOS e MA) apresentam um padrão de expressão de miRNAs diferentes devido ao tipo de células germinativas que eles apresentam no tecido epitelial do testículo. / Infertility is a public health problem with significant social, economic and psychological impact. Worldwide, the incidence of infertility in the general population is estimated at 10- 15%. Approximately 50% of infertility of couples is of male origin. In more than half of infertile men, the cause of infertility is unknown (idiopathic). Etiologically, male infertility has genetic and non-genetic causes. Among the best known genetic causes we found the mutation of the androgen receptor, the cystic fibrosis transmembrane conductance regulator (CFTR), classic chromosomal abnormalities, meiotic abnormalities and microdeletions of the Y chromosome. Chromosomal abnormalities are found much more frequently in infertile men, with an incidence of 4-16% in the incidence of 0.4% in the fertile population. Studies show that CNVs can also be related to male infertility, specifically in the failure of spermatogenesis. CNVs found in both the Y and autosomes chromosomes were also associated with possible failures in spermatogenesis. Another factor that may also be involved in male infertility is the deregulated expression of miRNAs. This work aimed to promote the analysis of large-scale distribution of CNVs and the transcriptional profile of miRNAs in testicular biopsy samples from patients with azoospermia. For the study of CNV we used the CytoScan HDTM Affymetrix methodology and the transcriptional profile of miRNAs in the samples was assessed by means of microarray technology from Affymetrix platform. For these analyzes we set up two study groups (Stop Maturation (MA) of Germ Cells and Sertoli Cell Only Syndrome (SCOS)) and compared them to a control group (obstructive azoospermia, normal spermatogenesis). Through analysis of CNVs, we found 94 CNVs in sexual and autosomes chromosomes, 35 (37%) were classified as benign CNVs, 24 (23%) as a potentially benign seven CNVs (7.4%) as pathogenic and 7 were classified as potentially pathogenic. All CNVs classified as pathogenic are present on the Y chromosome, five CNVs are of duplication type and two are deletion type. The duplication type CNV was found in MA patients and deletion type CNV was found in SCOS patient. We identified that CNVs overlap and when analyzed jointed - as a single CNV of each condition - they have a similar size. These CNVs have genes involved in spermatogenesis. CNVs classified as potentially pathogenic were present in autosomes and in the X chromosome. In these CNVs were present genes that were associated with failure in spermatogenesis. The analysis of the expression of miRNAs revealed a transitional profile much more altered in patients with SCOS. The two conditions presented exclusive miRNAs, but shared 30 miRNAs differentially expressed when compared to the control group. We identify two families of miRNAs (miR449 and miR34) which exhibit preferential expression in testis as differentially expressed in both conditions. Our results show that changes in the number of copies (CNVs) on the Y chromosome lead to male infertility and CNVs in autosomes and X chromosomes may lead to male infertility. The deletion type changes can lead to a failure of spermatogenesis greater than the duplication type changes. The differential expression of miRNAs in patients with testicular tissue histopathologic differences (SCOS and MA) has a different pattern of miRNA expression due to the type of germ cells they present in epithelial tissue of the testis.
4

« Les Sapeurs-pompiers, une identité temporelle de métier »

Kanzari, Ryad 17 December 2008 (has links) (PDF)
« Les Sapeurs-pompiers, une identité temporelle de métier » Résumé Notre thèse a pour objet le travail des sapeurs-pompiers. Ce travail est soumis à une évolution notable. D'un côté, l'évolution récente du métier, avec la croissance des interventions de « secours à victimes » affaiblit l'image du pompier « héroïque » pour le transformer en « travailleur social ». D'un autre côté, les pompiers maintiennent leurs engagements professionnels et répondent aux attentes de la population en mobilisant des valeurs collectives. Nos analyses tentent de montrer les multiples facettes de ce travail d'urgence en variant les objets d'analyse : négociation et conflit à propos du temps de travail, interventions lors de la catastrophe "AZF", observation de la vie quotidienne des pompiers, analyse de leurs discours assistée par ordinateur. Notre thèse peut être résumée rapidement. Le travail d'urgence des sapeurs-pompiers est supporté par une identité temporelle de métier. L'identité des pompiers se construit autour de valeurs partagées, de représentations tout autant subjectives qu'imprégnées d'histoire de la profession. Le pompier reste pompier même en dehors de ses activités professionnelles. L'organisation formalisée des interventions est accompagnée d'une organisation collective non-formalisée, tributaire des évènements, mais qui renvoie à un ensemble de croyances et d'engagements orientés vers l'aide des victimes. Les temporalités de cette profession caractérisent bien cette identité particulière : des horaires peu communs, l'urgence des interventions, le refus de la distinction entre vie privée et vie professionnelle, une disponibilité permanente. Ces temporalités sont bien sociales. Elles transgressent les frontières établies entre les activités, les manières de classer et de mesurer l'effort des individus. Le métier de sapeurs-pompiers met en cause les cadres habituels d'analyse du travail. Ce métier de la « protection » des individus est en effet exercé à 85% par des non-professionnels. Les « volontaires » mettent en relief ce type d'engagement professionnel très particulier, à la limite d'un salariat classique, caractérisé par une vie associative et par une activité professionnelle complémentaire. L'identité temporelle de métier permet de déplacer le regard sur le travail, son organisation et sur sa finalité économique. Elle s'articule autour du don de soi, dans des collectifs soudés, en vue d'un service public de protection, du secours et de la solidarité sociale.
5

De la Poudrerie nationale de Toulouse au Cancéropôle La catastrophe d'AZF dans les dynamiques territoriales d'un espace industriel urbain (1850-2008)

Cauhopé, Marion 28 January 2011 (has links) (PDF)
L'explosion de l'usine AZF, le 21 septembre 2001 à Toulouse, pose éminemment la question de la place d'activités " à risques " dans l'espace urbain, et remet brutalement en cause la légitimité d'usage des sols qu'avait acquise l'industrie. Partant de la catastrophe d'AZF, des discours sur l'espace qu'elle génère et les rapports de force qu'elle met en évidence, cette thèse analyse les relations que la société toulousaine entretient avec l'industrie chimique depuis l'implantation de la Poudrerie nationale de Toulouse au milieu du XIXe siècle. Les répercussions, matérielles et symboliques, de l'événement sont ainsi mises en perspective avec les dynamiques territoriales à l'œuvre sur l'espace urbain sinistré, dans une temporalité encadrant l'avant et l'après-catastrophe. Emblématique de ces changements, l'ONIA, ancêtre de l'usine AZF, était dans les années d'après-guerre une entreprise-phare de l'agglomération toulousaine. Celle-ci est entrée ensuite, du fait de l'évolution du projet industriel, de l'urbanisation des alentours et de la montée des préoccupations environnementales, dans un cycle de progressive déqualification, qui se conclut en avril 2002 par une décision de fermeture définitive. Les vifs débats sur l'avenir des installations chimiques laissent alors la place à l'émergence d'un projet de requalification du site industriel sinistré, autour d'un centre de recherche et de soins sur le cancer : le Cancéropôle. Affirmant une rupture avec le passé industriel du site, ce projet est au cœur des reconstructions successives à l'explosion de l'usine AZF. Il vise à réinscrire l'espace sinistré dans le développement économique et urbain d'une métropole qui " gagne ".
6

Exploration du génome et de l'épigénome dans les troubles sévères de la spermatogenèse chez l'homme

Faure, Anne-Karen 28 February 2007 (has links) (PDF)
L'objectif de ce travail est d'approfondir l'exploration du génome et de l'épigénome somatique et germinal chez des hommes présentant une atteinte sévère de la spermatogenèse. <br />Concernant le génome somatique, nous avons recherché la présence de mosaïques somatiques pour le chromosome Y microdélété chez 44 hommes infertiles, et aucune mosaïque n'a été détectée. Nous avons également analysé des réarrangements complexes du chromosome Y chez 3 patients infertiles. Cette étude nous a permis d'affiner leur caryotype et de mieux définir l'implication de l'anomalie du Y dans le phénotype d'infertilité. La ségrégation méiotique des chromosomes X, Y, 18, 13 et 21 a été étudiée par FISH multi-couleurs sur les spermatozoïdes de 31 patients infertiles. Nous avons montré des taux de disomies spermatiques augmentés chez la moitié de ces patients et identifié 4 facteurs de risques cliniques ou biologiques associés à l'augmentation des anomalies chromosomiques spermatiques. Enfin, concernant l'exploration de l'épigénome germinal, nous avons caractérisé le profil d'acétylation des histones par immunohistochimie sur les biopsies testiculaires de 33 patients atteints d'un syndrome des cellules de Sertoli isolées et/ou d'une tumeur testiculaire. Nous avons mis en évidence une hyperacétylation globale massive du noyau des cellules de Sertoli lorsque les tubes séminifères sont dépourvus de cellules méiotiques et post-méiotiques. Cette étude a révélé que l'acétylation des histones pourrait être impliquée dans le dialogue entre cellules germinales et cellules de Sertoli, et que sa dérégulation pourrait être associée à la genèse des cancers testiculaires. Ce travail ouvre des perspectives intéressantes pour la prise en charge des infertilités masculines sévères.
7

Lieux de rumeurs, lieux de co-mémorations : vers la reconstruction d'un passé : le cas de l'explosion de l'usine AZF / Places of rumors, places of commemorations : towards the reconstruction of a past : the AZF case

Demoures, Amélie 12 June 2015 (has links)
Dans une perspective psychosociale, l’objectif de cette thèse est de saisir l’aspect dynamique de la rumeur inter et intragroupe et son rôle dans la reconstruction des mémoires collectives dans des contextes spatio-temporels précis. A partir d’une étude monographique, sur la catastrophe de l’usine AZF survenue le 21 septembre à Toulouse, notre travail de thèse vise à expliquer ce qui est en jeu pour les groupes en présence, d’adhérer à et de faire perdurer ou non, telle ou telle « version ». En prenant en compte l'espace en tant que cadre social de la mémoire, nous nous intéressons à l'inscription spatiale de la rumeur, notamment au travers des pratiques commémoratives, comme une manière de s'approprier les lieux détruits par cette catastrophe. Notre recherche s’ancre dans le champ de la pensée sociale interrogeant les savoirs du sens commun et les manières de penser en contexte en fonction des insertions sociales des individus. Dans cette perspective nous adoptons le regard ternaire propre à la psychologie sociale pour interroger la rumeur dans une visée compréhensive du phénomène. Pour cela, nous avons mis en place une triangulation méthodologique (entretiens semi-directifs, observations, analyse de presse et questionnaires) afin de saisir la dynamique de la rumeur dans ses différentes temporalités, au travers de plusieurs groupes plus ou moins impliqués. L’analyse de l’ensemble des résultats confirme alors l’existence d’un phénomène rumoral à Toulouse plus de 10 ans après la catastrophe autour des origines de l’explosion au sein des différents lieux et groupes enquêtés. Le niveau d’implication des sujets et le degré des émotions négatives ressenties suite à l’événement sont alors des facteurs saillants expliquant d’une part, l’adhésion à une rumeur et, d’autre part, sa persistance. Toutefois, nos résultats mettent en évidence des variations de contenu du message de la rumeur selon les groupes en fonction de leur insertion et position sociales ainsi que du lien qui les rattachait à l’usine AZF. Notre recherche souligne ainsi combien le processus de la rumeur et les fonctions qu’elle remplit ne sont pas simplement animés par une mécanique cognitive de la pensée mais davantage motivés par des enjeux identitaires et mémoriels, selon les intérêts du moment pour le groupe. La permanence de la rumeur dans le temps et des lieux précis, témoigne alors de son rôle dans la transmission d’une mémoire collective, de sorte qu’elle soit valorisante pour les groupes. / In a psychosocial perspective, the aim of this research is to capture the dynamic aspect of inter and intragroup rumor and its role in the reconstruction of collective memories in specific spatiotemporal contexts. Based on a monographic study relative to the explosion of the AZF factory that occurred September 21th, 2001, in Toulouse, our PhD work aims to explain what is at stake for the groups involved, and why would they adopt and perpetuate or not a « version » of the story or another. Taking into account space as a social framework of memory, we will focus on the spatial inscription of the rumor, particularly through commemorative practices, considered as a way to re-appropriate places destroyed by the catastrophe. Our research belongs to the field of social thought, which question common sense knowledge and ways of thinking in specific contexts, depending on individuals’ social insertion. In this perspective, we adopt a « ternary » interpretation of facts, inherent to social psychology, to investigate rumor in a comprehensive approach. To fulfill this goal, we applied methodological triangulation in our research (semi-structured interviews, observations, press analyses and questionnaires), in order to seize the dynamic of rumor in its different temporalities, through several groups more or less involved. The analysis of all results confirm the existence of a rumor phenomenon in Toulouse over 10 years after the disaster and related to the origins of the explosion, in the different investigated places and groups. The level of implication and the level of negative emotions felt after the event are salient factors to explain both the adhesion to a rumor and its persistence. However, our results highlight variations in the message content for different groups depending on their social insertion and position as well as the bond that relationship that bonded them to the AZF factory. Our research affirm that the rumor process and functions are not simply animated by a cognitive mechanisms of though but rather motivated by identity and memory issues, depending on the group’s present interest. The persistence of rumor in specific times and places demonstrate its role in the transmission of a collective memory, in a gratifying way for the involved groups.
8

Orthogonality and Codon Preference of the Pyrrolysyl-tRNA Synthetase-tRNAPyl pair in Escherichia coli for the Genetic Code Expansion

Odoi, Keturah 2012 May 1900 (has links)
Systematic studies of basal nonsense suppression, orthogonality of tRNAPyl variants, and cross recognition between codons and tRNA anticodons are reported. E. coli displays detectable basal amber and opal suppression but shows a negligible ochre suppression. Although detectable, basal amber suppression is fully inhibited when a pyrrolysyl-tRNA synthetase (PylRS)-tRNAPyl_CUA pair is genetically encoded. trnaPyl_CUA is aminoacylated by an E. coli aminoacyl-tRNA synthetase at a low level, however, this misaminoacylation is fully inhibited when both PylRS and its substrate are present. Besides that it is fully orthogonal in E. coli and can be coupled with PylRS to genetically incorporate a NAA at an ochre codon, tRNAPyl_UUA is not able to recognize an UAG codon to induce amber suppression. This observation is in direct conflict with the wobble base pair hypothesis and enables using an evolved M. jannaschii tyrosyl-tRNA synthetase-tRNAPyl_UUA pair and the wild type or evolved PylRS-tRNAPyl_UUA pair to genetically incorporate two different NAAs at amber and ochre codons. tRNAPyl_UCA is charged by E. coli tryptophanyl-tRNA synthetase, thus not orthogonal in E. coli. Mutagenic studies of trnaPyl_UCA led to the discovery of its G73U form which shows a higher orthogonality. Mutating trnaPyl_CUA to trnaPyl_UCCU not only leads to the loss of the relative orthogonality of tRNAPyl in E. coli but also abolishes its aminoacylation by PylRS.

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