Search results for " tRNA"
showing 8 items of 8 documents
A bi-allelic loss-of-function SARS1 variant in children with neurodevelopmental delay, deafness, cardiomyopathy, and decompensation during fever
2021
Aminoacyl-tRNA synthetases (aaRS) are ubiquitously expressed enzymes responsible for ligating amino acids to their cognate tRNA molecules through an aminoacylation reaction. The resulting aminoacyl-tRNA is delivered to ribosome elongation factors to participate in protein synthesis. Seryl-tRNA synthetase (SARS1) is one of the cytosolic aaRSs and catalyzes serine attachment to tRNASer . SARS1 deficiency has already been associated with moderate intellectual disability, ataxia, muscle weakness, and seizure in one family. We describe here a new clinical presentation including developmental delay, central deafness, cardiomyopathy, and metabolic decompensation during fever leading to death, in a…
Differentially Expressed tRNA-Derived Small RNAs Co-Sediment Primarily with Non-Polysomal Fractions in Drosophila
2017
Recent studies point to the existence of poorly characterized small regulatory RNAs generated from mRNAs, rRNAs and tRNAs. To explore the subcellular location of tRNA-derived small RNAs, 0–1 and 7–8 h Drosophila embryos were fractionated on sucrose density gradients. Analysis of 12,553,921 deep-sequencing reads from unfractionated and fractionated Drosophila embryos has revealed that tRFs, which are detected mainly from the 5’ends of tRNAs, co-sediment with the non-polysomal fractions. Interestingly, the expression levels of a subset of tRFs change temporally following thematernal-to-zygotic transition in embryos. We detected non-polysomal association of tRFs in S2 cells as well. Differenti…
Investigating the inhibition of FTSJ1 a tryptophan tRNA-specific 2’-O-methyltransferase by NV TRIDs, as a mechanism of readthrough in nonsense mutate…
2023
Abstract: Cystic Fibrosis (CF) is an autosomal recessive genetic disease caused by mutations in the CFTR gene, coding for the CFTR chloride channel. About 10% of the CFTR gene mutations are "stop" mutations, which generate a Premature Termination Codon (PTC), thus synthesizing a truncated CFTR protein. A way to bypass PTC relies on ribosome readthrough, which is the ri-bosome’s capacity to skip a PTC, thus generating a full-length protein. “TRIDs” are molecules exerting ribosome readthrough; for some, the mechanism of action is still under debate. We in-vestigate a possible mechanism of action (MOA) by which our recently synthesized TRIDs, namely NV848, NV914, and NV930, could exert their r…
Naturaleza dinámica de MnmG. Una flavoenzima ancestral modificadora de tRNAs bacterianos y mitocondriales
2016
La modificación del tRNA es un proceso universal presente en todos los organismos y orgánulos de origen endosimbionte como mitocondria y cloroplasto. Las modificaciones de la uridina localizada en la posición de tambaleo del anticodón (conocida abreviadamente como U34) que implican la adición de un grupo aminometileno (o derivado) en la posición 5 (xm5) son especialmente importantes en el proceso de reconocimiento codón-anticodón y, por tanto, para una descodificación óptima del mensaje genético. La ausencia de estas modificaciones se asocia con un fenotipo pleiotrópico e incluso letalidad en determinadas condiciones. Las modificaciones del tipo xm5 son introducidas en la U34 de los tRNAs d…
La psicoteràpia trnasforma la praxis moral?
2018
espanolEsta investigacion se inicio en el ano 2014 con el objetivo principal de conocer si los pacientes que realizan una psicoterapia cambian su praxis moral. Otros objetivos eran descubrir asociaciones significativas entre subgrupos de la muestra. La muestra se capto principalmente por internet. Los datos recogidos son: sociodemograficos; el cuestionario de personalidad MCMI y la evaluacion de unos dilemas eticos con respuestas dicotomicas y con una explicacion descriptiva. Los dilemas sedisenaron especificamente para la investigacion. El analisis se ha efectuado con herramientas cualitativas (Atlas.ti) y cuantitativas (SPSS) sobre una muestra valida de 85 sujetos, y con la hipotesis nula…
Caracterización funcional de GTPBP3: una proteína G implicada en la modificación de tRNAs mitocondriales.
2015
Determinadas enfermedades mitocondriales, como MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes), MERRF (myoclonus epilepsy associated with ragged-red-fibers), cardiomiopatía hipertrófica y acidosis láctica dependiente de GTPBP3, cardiomiopatía hipertrófica infantil y acidosis láctica dependiente de MTO1 y fallo hepático infantil agudo dependiente de TRMU, están asociadas con una disfunción severa del sistema de fosforilación oxidativa (OXPHOS) que, se cree, podría ser resultado de defectos en la modificación postranscripcional de la uridina localizada en la posición de tambaleo (U34) de ciertos tRNAs mitocondriales (mt-tRNAs) y, por consiguiente, de u…
Effects of 5-Azacitidine on Dnmt2/Trdmt1 expression levels and endoplasmic reticulum stress in cellular models of insulinoma
2021
Diabetes mellitus affects people all over the world of all ages or social groups making it a worldwide healthcare challenge. Moreover, untreated or badly treated diabetes carries a risk of serious complications including premature death (IDF Diabetes Atlas 9th edition, 2019). The main symptom of diabetes is insulin secretion and/or action disorder leading to hyperglycemia what results in impaired carbohydrate, fat, and protein metabolism (“Diagnosis and Classification of Diabetes Mellitus,” 2013). Dnmt2/ Trdmt1 in its structure and sequence is similar to DNA methyltransferases, however, it has been shown that mainly methylates aspartic acid transfer RNA, specifically at the cytosine-38 resi…
The Mitochondrial tRNASer(UCN) Gene: A Novel m.7484A>G Mutation Associated with Mitochondrial Encephalomyopathy and Literature Review
2023
Mitochondrial tRNASer(UCN) is considered a hot-spot for non-syndromic and aminoglycoside-induced hearing loss. However, many patients have been described with more extensive neurological diseases, mainly including epilepsy, myoclonus, ataxia, and myopathy. We describe a novel homoplasmic m.7484A>G mutation in the tRNASer(UCN) gene affecting the third base of the anticodon triplet in a girl with profound intellectual disability, spastic tetraplegia, sensorineural hearing loss, a clinical history of epilepsia partialis continua and vomiting, typical of MELAS syndrome, leading to a myoclonic epilepticus status, and myopathy with severe COX deficiency at muscle biopsy. The mutation was also …