scholarly journals A tRNA-mimic Strategy to Explore the Role of G34 of tRNAGly in Translation and Codon Frameshifting

2019 ◽  
Vol 20 (16) ◽  
pp. 3911 ◽  
Author(s):  
Janvier ◽  
Despons ◽  
Schaeffer ◽  
Tidu ◽  
Martin ◽  
...  
Keyword(s):  
Codon Position ◽  
Variable Number ◽  
The Other ◽  
Loop Structure ◽  
Anticodon Loop ◽  
Reading Frame ◽  
The Third ◽  
Genome Wide ◽  
Trna Isoacceptors

Decoding of the 61 sense codons of the genetic code requires a variable number of tRNAs that establish codon-anticodon interactions. Thanks to the wobble base pairing at the third codon position, less than 61 different tRNA isoacceptors are needed to decode the whole set of codons. On the tRNA, a subtle distribution of nucleoside modifications shapes the anticodon loop structure and participates to accurate decoding and reading frame maintenance. Interestingly, although the 61 anticodons should exist in tRNAs, a strict absence of some tRNAs decoders is found in several codon families. For instance, in Eukaryotes, G34-containing tRNAs translating 3-, 4- and 6-codon boxes are absent. This includes tRNA specific for Ala, Arg, Ile, Leu, Pro, Ser, Thr, and Val. tRNAGly is the only exception for which in the three kingdoms, a G34-containing tRNA exists to decode C3 and U3-ending codons. To understand why G34-tRNAGly exists, we analysed at the genome wide level the codon distribution in codon +1 relative to the four GGN Gly codons. When considering codon GGU, a bias was found towards an unusual high usage of codons starting with a G whatever the amino acid at +1 codon. It is expected that GGU codons are decoded by G34-containing tRNAGly, decoding also GGC codons. Translation studies revealed that the presence of a G at the first position of the downstream codon reduces the +1 frameshift by stabilizing the G34•U3 wobble interaction. This result partially explains why G34-containing tRNAGly exists in Eukaryotes whereas all the other G34-containing tRNAs for multiple codon boxes are absent.

Role of pro-opiomelanocortin-derived peptides in the regulation of steroid production by human fetal adrenal cells in culture

1983 ◽  
Vol 97 (3) ◽  
pp. 357-367 ◽  
Author(s):  
Andrew Baird ◽  
K. W. Kan ◽  
Samuel Solomon
Keyword(s):  
Peptide Hormones ◽  
The Other ◽  
Dehydroepiandrosterone Sulphate ◽  
Steroid Production ◽  
Adrenal Cells ◽  
The Third ◽  
Cells In Culture

Synthetic (1–39)ACTH, (1–24)ACTH, (18–39)ACTH, α-MSH, met-enkephalin and α-, βand γ-endorphin were tested for their ability to stimulate steroidogenesis by human fetal adrenal cells in culture. Adrenal cells were incubated with peptide hormones for two periods of 24 h. On the third day of the experiment the cells were incubated with progesterone (4 μg/2 ml) for 8 h. At the doses tested only (1–39)ACTH, (1–24)ACTH and α-MSH stimulated steroidogenesis. None of the other peptides had any corticotrophic effect on the formation of cortisol, corticosterone or dehydroepiandrosterone sulphate (DHAS). At the highest doses tested, α-MSH (100 μg/2 ml) had a corticotrophic effect that was not different from that obtained with 20 ng (1–39)ACTH or (1–24)ACTH. At the lower doses (0·2–2 μg/2 ml), α-MSH stimulated the formation of DHAS (P<0·01) without stimulating the formation of cortisol.

scholarly journals One of the tightly clustered genes of the mouse surfeit locus is a highly expressed member of a multigene family whose other members are predominantly processed pseudogenes.

1988 ◽  
Vol 8 (9) ◽  
pp. 3898-3905 ◽  
Author(s):  
C Huxley ◽  
T Williams ◽  
M Fried
Keyword(s):  
Multigene Family ◽  
Open Reading Frame ◽  
The Other ◽  
Base Pairs ◽  
Regulation Of Expression ◽  
Reading Frame ◽  
Processed Pseudogenes ◽  
Dna Fragment ◽  
Basic Polypeptide

The mouse surfeit locus is unusual in that it contains a number of closely clustered genes (Surf-1, -2, and -4) that alternate in their direction of transcription (T. Williams, J. Yon, C. Huxley, and M. Fried, Proc. Natl. Acad. Sci. USA 85:3527-3530, 1988). The heterogeneous 5' ends of Surf-1 and Surf-2 are separated by 15 to 73 base pairs (bp), and the 3' ends of Surf-2 and Surf-4 overlap by 133 bp (T. Williams and M. Fried, Mol. Cell. Biol. 6:4558-4569, 1986; T. Williams and M. Fried, Nature (London) 322:275-279, 1986). A fourth gene in this locus, Surf-3, which is a member of a multigene family, has been identified. The poly(A) addition site of Surf-3 lies only 70 bp from the poly(A) addition site of Surf-1. Transcription of Surf-3 has been studied in the absence of the other members of its multigene family after transfection of a cloned genomic mouse DNA fragment, containing the Surf-3 gene, into heterologous monkey cells. Surf-3 specifies a highly expressed 1.0-kilobase mRNA that contains a long open reading frame of 266 amino acids, which would encode a highly basic polypeptide (23% Arg plus Lys). The other members of the Surf-3 multigene family are predominantly, if not entirely, intronless pseudogenes with the hallmarks of being generated by reverse transcription. The role of the very tight clustering on regulation of expression of the genes in the surfeit locus is discussed.

Inspiratory elevation of the ribs in the dog: primary role of the parasternals [published errata appear in J Appl Physiol 1991 Aug;71(2):following Table of Contents and 1991 Dec;71(6):following Author Index]

1991 ◽  
Vol 70 (4) ◽  
pp. 1447-1455 ◽  
Author(s):  
A. De Troyer
Keyword(s):  
Quantitative Analysis ◽  
Axial Displacement ◽  
The Other ◽  
Primary Role ◽  
Intercostal Muscles ◽  
The Third ◽  
Inspiratory Activity ◽  
Fourth Rib

To assess the relative contributions of the different groups of inspiratory intercostal muscles to the cranial motion of the ribs in the dog, we have measured the axial displacement of the fourth rib and recorded the electromyograms of the parasternal intercostal, external intercostal, and levator costae in the third interspace in 15 anesthetized animals breathing at rest. In eight animals, the parasternal intercostals were denervated in interspaces 1-5. This procedure caused a marked increase in the amount of external intercostal and levator costae inspiratory activity, and yet the inspiratory cranial motion of the rib was reduced by 55%. On the other hand, the external intercostals in interspaces 1-5 were sectioned in seven animals, and the reduction in the cranial rib motion was only 22%; the amount of parasternal and levator costae activity, however, was unchanged. When the parasternals in these animals were subsequently denervated, the levator costae inspiratory activity increased markedly, but the inspiratory cranial motion of the rib was abolished or reversed into an inspiratory caudal motion. These studies thus confirm that, in the dog breathing at rest, the parasternal intercostals have a larger role than the external intercostals and levator costae in causing the cranial motion of the ribs during inspiration. A quantitative analysis suggests that the parasternal contribution is approximately 80%.

scholarly journals Association between spectator and other roles in school bullying

2016 ◽  
Vol 26 (3) ◽  
pp. 352
Author(s):  
Marcela Almeida Zequinão ◽  
Pâmella De Medeiros ◽  
Beatriz Pereira ◽  
Fernando Luiz Cardoso
Keyword(s):  
Public Schools ◽  
Negative Reinforcement ◽  
Strong Association ◽  
School Bullying ◽  
The Other ◽  
Seventh Grade ◽  
Santa Catarina ◽  
The Third ◽  
Aggressive Behaviours

Introduction: The school bullying is characterized by repetitiveness of aggression and the intentionality to injure or cause suffering to others. The bystanders to this phenomenon tend to be mainly responsible for the course that bullying will take and its results. Objective: To analyse the association between the role of bystander with the other possible roles played in bullying. Method: A total of 409 children from the third to seventh grade participated in this study, with an average age of 11 years (SD = 1.61), enrolled in two municipal public schools in Florianópolis, Santa Catarina, Brazil. The instruments used were: one of the scales of the Questionnaire for the Study of Violence Among Peers, to identify bystanders, and the Olweus Questionnaire, to describe the possible roles played in school bullying. Results: It was found that most of the participants assumed the role of bystander in school bullying. However, an association was found with regard to gender and being a bystander. Also, strong association was found between being a bystander and the other roles played in bullying, primarily in relation to the bullies. Conclusion: These results reinforce the importance of bystanders in these aggressions, not only because they represent most of the participants, but mainly because of the positive or negative reinforcement they can offer in these aggressive behaviours. Therefore, the incentive and the encouragement of these students to denounce the aggressors, as well as defending the victims is essential to reduce school bullying.

Socio-Cognitive Model of Trust

2009 ◽  
pp. 2316-2323
Author(s):  
Rino Falcone ◽  
Cristiano Castelfranchi
Keyword(s):  
Decision Making ◽  
Cognitive Model ◽  
Frame Of Reference ◽  
The Other ◽  
The Internet ◽  
The Third ◽  
Interaction Traces ◽  
Cooperative Models ◽  
Support Decision Making

Humans have learned to cooperate in many ways and in many environments, on different tasks, and for achieving different and several goals. Collaboration and cooperation in their more general sense (and, in particular, negotiation, exchange, help, delegation, adoption, and so on) are important characteristics - or better, the most foundational aspects - of human societies (Tuomela, 1995). In the evolution of cooperative models, a fundamental role has been played by diverse constructs of various kinds (purely interactional, technical-legal, organizational, socio-cognitive, etc.), opportunely introduced (or spontaneously emerged) to support decision making in collaborative situations. The new scenarios we are destined to meet in the third millennium transfigure the old frame of reference, in that we have to consider new channels and infrastructures (i.e., the Internet), new artificial entities for cooperating with artificial or software agents, and new modalities of interaction (suggested/imposed by both the new channels and the new entities). In fact, it is changing the identification of the potential partners, the perception of the other agents, the space-temporal context in which interaction happen, the nature of the interaction traces, the kind and role of the authorities and guarantees, etc. For coping with these scenarios, it will be necessary to update the traditional supporting decision-making constructs. This effort will be necessary especially to develop the new cybersocieties in such a way as not to miss some of the important cooperative characteristics that are so relevant in human societies.

scholarly journals The role of second coordination-sphere interactions in incommensurately modulated structures, using β-K5Yb(MoO4)4 as an example

2005 ◽  
Vol 61 (4) ◽  
pp. 400-406 ◽  
Author(s):  
Alla Arakcheeva ◽  
Gervais Chapuis ◽  
Vâclav Petricek ◽  
Vladimir Morozov
Keyword(s):  
Coordination Sphere ◽  
Driving Force ◽  
The Other ◽  
Structure Model ◽  
Unit Cell Parameters ◽  
Cell Parameters ◽  
The Third ◽  
Modulated Structures ◽  
Coordination Spheres

The incommensurate palmierite-like structure of β-K5Yb(MoO4)4, potassium ytterbium tetramolydate, has been refined in the (3 + 1)-dimensional monoclinic superspace group X2/m(0ρ0)00, with X = [0 0 0 0; ½ ½ 0 0; 0 0 ½ ½; ½ ½ ½ ½] and the unit-cell parameters a = 10.4054 (16), b = 6.1157 (12), c = 19.7751 (18) Å, β = 136.625 (10)°; q = 0.6354 (30)b*. The occupations of the K and Yb atomic positions are described by crenel functions. The structure model reveals a balanced interaction between the atoms of the first and second coordination spheres. It is shown that the third coordination sphere should not be neglected in studies of modulated structures. The ordering of the K and Yb atoms appears to be the driving force for the modulation of all the other atoms.

scholarly journals METTL2 forms a complex with the DALRD3 anticodon-domain binding protein to catalyze formation of 3-methylcytosine in specific arginine tRNA isoacceptors

2019 ◽  
Author(s):  
Jenna M. Lentini ◽  
Dragony Fu
Keyword(s):  
Binding Protein ◽  
Complete Loss ◽  
Human Cells ◽  
Binding Domain ◽  
Biological Role ◽  
Anticodon Loop ◽  
Sequence Elements ◽  
Trna Isoacceptors

AbstractIn mammals, a subset of arginine tRNA isoacceptors are methylated in the anticodon loop by the METTL2 methyltransferase to form the 3-methylcytosine (m3C) modification. However, the mechanism by which METTL2 identifies specific arginine tRNAs for m3C formation as well as the biological role of m3C in mammals is unknown. Here, we show that human METTL2 forms a complex with DALR anticodon binding domain containing 3 (DALRD3) protein in order to recognize particular arginine tRNAs destined for m3C modification. Using biochemical reconstitution, we find that METTL2-DALDR3 complexes catalyze m3C formation in vitro that is dependent upon sequence elements specific to certain arginine tRNAs. Notably, DALRD3-deficient human cells exhibit nearly complete loss of the m3C modification in arginine tRNAs. These findings uncover an unexpected function for the DALRD3 protein in the targeting of distinct arginine tRNAs for m3C modification.

scholarly journals Intertextuality of Political Discourse in Germany (on the Example of “Political Ash Wedfnesday”)

2020 ◽  
pp. 76-90
Author(s):  
Maria A. Elizarieva ◽  
Marina A. Chigasheva ◽  
Boris Blahak ◽  
Maria Yu. Mikhina
Keyword(s):  
Literary Work ◽  
The Other ◽  
The Political ◽  
Ordinary People ◽  
Television Commercial ◽  
The Third ◽  
Christian Social Union ◽  
The One ◽  
The Relationship

The article is devoted to the role of intertext in public speeches of politicians of the Christian Social Union in Bavaria within the framework of the “political ash Wednesday”. On the example of the speeches of M. Söder, A. Scheuer and M. Blume in 2018, the relationship between the type of intertext and its pretext, on the one hand, and the speaker’s intention, on the other, was analyzed. As a result of the analysis of 23 intertextual inclusions, four intentions were revealed, among which (48 %) criticism of political opponents (SDPG, “The Greens”, AfD, “Free Voters”) prevails. Quotes from representatives of these parties, political slogans, a paraphrase of the name of the eco-movement and a quote from an artist are used to express it. As the intertextual analysis showed, to verbalize the second intention (appeal to authoritative opinion and emphasize the continuity of the party course), the former chairman of the CSU F. J. Strauss is cited, while the third intention (opposing Bavaria to the rest of Germany) is implemented using a quote from the Bavarian anthem, a paraphrase of a television commercial and quotations from a literary work. In addition, the authors found that the fourth intention (emphasizing the dialogic nature of communication with ordinary people) is found only in M. Söder’s speech in the form of a retelling of his dialogues with ordinary citizens.

scholarly journals The role of NDI on the failure analysis of an aircraft propeller hub

2018 ◽  
Vol 188 ◽  
pp. 04021
Author(s):  
Iordanis Spyroglou ◽  
Angelos Koutsomichalis ◽  
Panos Stavropoulos ◽  
Nikolaos Roussis
Keyword(s):  
High Stress ◽  
Sem Analysis ◽  
The Other ◽  
Propeller Blade ◽  
High Stress Concentration ◽  
The Third ◽  
Stage Of Development ◽  
Corrosion Pits ◽  
Non Destructive

This paper analyses the causes of an incident in an aircraft propeller hub. The aluminum alloy propeller blade hub was detached from the plane bearing one of its two blades with the other one being jettisoned away. Stereoscopic examination of the fractured hub revealed that it was initially cracked by fatigue, with the crack initiating on the root of the third and fourth spirals and propagating form the inner to the outer. SEM analysis showed that the crack epicentres were created very close or/and on the spiral roots and were attributed to microcracks from corrosion pits and high stress concentration. Non Destructive Inspection was both used on the other side of the hub and the remaining three hubs of the plane and confirmed the presence of cracks similar to those which caused the fatigue failure of the fractured hub but at earliest stage of development.

History, Identity, and the Present

2020 ◽  
pp. 251-290
Author(s):  
Donald Bloxham
Keyword(s):  
Historical Consciousness ◽  
The Other ◽  
Conceptual Difficulty ◽  
Fourth Section ◽  
The Third ◽  
Past Action ◽  
Present Part ◽  
Definition Of ◽  
The Relationship

part 4 History, Identity, and the Present Part 4 considers the role of historical consciousness in shaping present-day identity. It is critical of prejudicial ‘Identity History’ while enjoining historians to embrace their roles in historical arguments pertaining to identity. The first section clarifies what falls outside the definition of ‘Identity History’, noting that much excellent scholarship pertains to identity and even serves identity goals without being prejudicial. The second section highlights where historians working on identity matters are likely to fall into conceptual difficulty. Is the relationship between past ‘them’ and present ‘us’ a matter of identity or difference or a bit of both? Identity History is inconsistent here, with different attitudes taken depending on whether that past behaviour was good or bad by present lights. There are consequences for the historian’s engagement with past rights and wrongs, harms and benefits, because claims on these matters constitute stakes in the identity game whose winner gets to decide what is desirable in the here and now. The third section develops such themes and distinguishes between more and less appropriate idioms for characterizing the relationship between contemporary polities and groups on one hand and the deeds of relevant ‘forebears’ on the other hand. It is a mistake to talk of contemporary guilt, or for that matter virtue, in light of what one’s predecessors did, but the language of shame or pride may be appropriate. The fourth section addresses the material legacies of past action, considering matters of compensation and redistribution. The concluding section returns to broader principles.

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