Search results for "Methylation"
showing 10 items of 607 documents
Cytosine methylation of tRNA-Asp by DNMT2 has a role in translation of proteins containing poly-Asp sequences
2015
AbstractThe Dnmt2 RNA methyltransferase catalyses the methylation of C38 in the anticodon loop of tRNA-Asp, but the molecular role of this methylation is unknown. Here, we report that mouse aspartyl-tRNA synthetase shows a four to fivefold preference for C38-methylated tRNA-Asp. Consistently, a 30% reduced charging level of tRNA-Asp was observed in Dnmt2 knockout (KO) murine embryonic fibroblast cells. Gene expression analysis with fluorescent reporter proteins fused to an N-terminal poly-Asp sequence showed that protein synthesis of poly-Asp-tagged reporter proteins was reduced in Dnmt2 KO cells as well. The same effect was observed with endogenous proteins containing poly-Asp sequences, i…
Comparative analysis of production and purification of homo- and hetero-polysaccharides produced by lactic acid bacteria
2013
2 figuras, 2 tablas
NFATc1 Is Transcriptionally Activated in Chronic Lymphocytic Leukemia (CLL) By Promotor DNA-Hypomethylation Which Correlates with in-Vitro Vulnerabil…
2014
Abstract Chronic lymphocytic leukemia (CLL), the most frequent adult leukemia in Western countries, is characterized by progressive accumulation of mature, monoclonal B lymphocytes in blood, bone marrow, and lymphoid tissues. In the pathogenesis and treatment of CLL, B cell receptor (BCR) signaling plays a crucial role, and aberrations in downstream pathways that become activated in CLL need to be better defined. One downstream target of BCR signaling is NFATc1, a transcription factor with a high oncogenic and transforming potential. Employing a genome-wide comparative DNA methylation analysis the NFATc1 5’ region was identified to be DNA hypomethylated in CLL patient samples. The pilot ser…
Biotic methylation of mercury by intestinal and sulfate-reducing bacteria and their potential role in mercury accumulation in the tissue of the soil-…
2014
Abstract Monomethylmercury as one of the most toxic mercury species influences the health and development of higher organisms and tends to accumulate in the tissue of animals and humans. The aim of this study was to explore the mercury methylating capability of (1) intestinal microbiota of the soil-living earthworm Eisenia foetida (E. foetida) and (2) intestinal sulfate reducing-bacteria in pure cultures. After exposing animals to inorganic mercury chloride (4 mg kg−1 Hg2+) in soil and sterile soil for ten days, the amount of methylmercury in tissue was measured. Despite sterilization of soil, the accumulation of the organic mercury species in tissue was 51 ng g−1. To elucidate the potentia…
The Histone Acetyl-Transferase MOZ Cooperates with the Histone Methyl-Transferase MLL to Regulate HOX Gene Expression in Human Hematopoietic Stem Cel…
2008
Abstract MOZ (MOnocytic leukaemia Zinc finger protein) (also called MYST3 or KAT6A) is a member of the MYST family of HATs which likely acetylate H4K16. The MLL (MixedLineageLeukemia) gene is a frequent target for recurrent chromosomal translocations found in AML and ALL. MLL (KMT2A) is a methyl-transferase targeting H3K4. It was shown that MOZ/CBP leukemia, as observed in MLL-rearranged leukemias, harbors abnormal levels of homeobox (HOX) genes expression. HOX transcription factors have a crucial function in hematopoiesis regulation. In addition, HOXA5, HOXA7, and HOXA9 are often considered to be pivotal HOX genes for MLL transformation, constituting downstream targets of MLL. In our study…
Isotope Fractionation of Selenium During Fungal Biomethylation by Alternaria alternata
2011
The natural abundance of stable Se isotopes may reflect sources and formation conditions of methylated Se. We aimed at (1) quantifying the degree of methylation of selenate [Se(VI)] and (hydro)selenite [Se(IV)] by the fungus Alternaria alternata at pH 4 and 7 and (2) determining the effects of these different Se sources and pH values on 82Se/76Se ratios (δ82/76Se) in methylselenides. Alternaria alternata was incubated with Se(VI) and Se(IV) in closed microcosms for 11-15 days and additionally with Se(IV) for 3-5 days at 30 °C. We determined Se concentrations and δ82/76Se values in source Se(VI) and Se(IV), media, fungi, and trapped methylselenides. In Se(VI) incubations, methylselenide vola…
Study of the epi- / genomic dysregulation of breast cancer in women under 35 years and evaluation of cellular models
2019
El cáncer de mama tiene la tasa de incidencia más alta de todos los cánceres en mujeres en todo el mundo. Este cáncer suele tener un excelente pronóstico con un 80% de supervivencia. Aunque las mujeres menores de 35 años representan el 3-4% del total de casos diagnosticados, sus tumores se caracterizan por ser más grandes, más proliferativos y con una mayor representación de subtipos más agresivos y de peor pronóstico. Las transformaciones neoplásicas se asocian con alteraciones en la metilación del ADN, que incluyen tanto la hipometilación global como la hipermetilación específica. Por otro lado, los miRNAs son pequeñas moléculas no codificantes con un papel importante en la regulación de …
Do epigenetic clocks provide explanations for sex differences in lifespan? A cross-sectional twin study
2021
ABSTRACTBackgroundThe sex gap in life expectancy has been narrowing in Finland over the past four to five decades; however, on average, women still live longer than men. Epigenetic clocks are markers for biological aging that predict lifespan. In this study, we examined the mediating role of lifestyle factors on the association between sex and biological aging in younger and older adults.MethodsOur sample included same-sex younger and older twins (21-42-y, n = 1110; 50-76-y, n = 763) and younger opposite-sex twins (21-30-y, n = 302). Blood-based DNA methylation (DNAm) was used to compute epigenetic age acceleration by four epigenetic clocks as a measure of biological aging. Path modelling w…
Electrochemical Installation of CFH 2 −, CF 2 H−, CF 3 −, and Perfluoroalkyl Groups into Small Organic Molecules
2021
Electrosynthesis can be considered a powerful and sustainable methodology for the synthesis of small organic molecules. Due to its intrinsic ability to generate highly reactive species under mild conditions by anodic oxidation or cathodic reduction, electrosynthesis is particularly interesting for otherwise challenging transformations. One such challenge is the installation of fluorinated alkyl groups, which has gained significant attention in medicinal chemistry and material science due to their unique physicochemical features. Unsurprisingly, several electrochemical fluoroalkylation methods have been established. In this review, we survey recent developments and established methods in the…
Mapping and Quantification of tRNA 2′-O-Methylation by RiboMethSeq
2018
Current development of epitranscriptomics field requires efficient experimental protocols for precise mapping and quantification of various modified nucleotides in RNA. Despite important advances in the field during the last 10 years, this task is still extremely laborious and time-consuming, even when high-throughput analytical approaches are employed. Moreover, only a very limited subset of RNA modifications can be detected and only rarely be quantified by these powerful techniques. In the past, we developed and successfully applied alkaline fragmentation-based RiboMethSeq approach for mapping and precise quantification of multiple 2'-O-methylation residues in ribosomal RNA. Here we descr…