Search results for "TRANSFERASE"

Effects of an earth-strength magnetic field on pineal melatonin synthesis in pigeons

1987

Molecular epidemiology of Acinetobacter baumannii in Iran: endemic and epidemic spread of multiresistant isolates

2014

Objectives We examined the molecular epidemiology of Acinetobacter baumannii clinical isolates from two cities (Tehran and Tabriz) of Iran. Methods DiversiLab repetitive extragenic palindromic PCR (rep-PCR), multilocus sequence typing and sequence group multiplex PCR were performed. The presence of resistance mechanisms including metallo-β-lactamases, extended-spectrum β-lactamases, OXA carbapenemases, aminoglycoside-modifying enzymes and RNA methylases was also investigated. Results DiversiLab rep-PCR identified 11 clusters and 11 singleton isolates. Twelve sequence types (STs), including six novel types, were identified. Sequence groups (SGs) 1-3 as well as five additional banding pattern…

Dissemination of a Carbapenem-Resistant Acinetobacter baumannii Strain Belonging to International Clone II/Sequence Type 2 and Harboring a Novel AbaR…

2013

ABSTRACT An outbreak of hospital-acquired Acinetobacter baumannii infections, caused by a bla OXA-23 -positive carbapenem-resistant strain belonging to international clone II/ST2, was detected in Latvia. The strain was partially equipped with the armA gene and the intI1-aacA4-catB8-aadA1-qacE Δ 1 class 1 integron. In addition, the strain carried AbaR25, a novel AbaR4-like resistance island of ∼46,500 bp containing structures similar to the previously described AbaR22 and Tn 6167 islands. AbaR25 was characterized by the occurrence of a second copy of Tn 6022a interrupted by Tn 2006 carrying the bla OXA-23 gene.

Customised next-generation sequencing multigene panel to screen a large cohort of individuals with chromatin-related disorder

2020

BackgroundThe regulation of the chromatin state by epigenetic mechanisms plays a central role in gene expression, cell function, and maintenance of cell identity. Hereditary disorders of chromatin regulation are a group of conditions caused by abnormalities of the various components of the epigenetic machinery, namely writers, erasers, readers, and chromatin remodelers. Although neurological dysfunction is almost ubiquitous in these disorders, the constellation of additional features characterizing many of these genes and the emerging clinical overlap among them indicate the existence of a community of syndromes. The introduction of high-throughput next generation sequencing (NGS) methods f…

m6A RNA methylation of major satellite repeat transcripts facilitates chromatin association and RNA:DNA hybrid formation in mouse heterochromatin

2021

Abstract Heterochromatin has essential functions in maintaining chromosome structure, in protecting genome integrity and in stabilizing gene expression programs. Heterochromatin is often nucleated by underlying DNA repeat sequences, such as major satellite repeats (MSR) and long interspersed nuclear elements (LINE). In order to establish heterochromatin, MSR and LINE elements need to be transcriptionally competent and generate non-coding repeat RNA that remain chromatin associated. We explored whether these heterochromatic RNA, similar to DNA and histones, may be methylated, particularly for 5-methylcytosine (5mC) or methyl-6-adenosine (m6A). Our analysis in mouse ES cells identifies only b…

The 18S ribosomal RNA m 6 A methyltransferase Mettl5 is required for normal walking behavior in Drosophila

2020

RNA modifications have recently emerged as an important layer of gene regulation. N6-methyladenosine (m6A) is the most prominent modification on eukaryotic messenger RNA and has also been found on noncoding RNA, including ribosomal and small nuclear RNA. Recently, several m6A methyltransferases were identified, uncovering the specificity of m6A deposition by structurally distinct enzymes. In order to discover additional m6A enzymes, we performed an RNAi screen to deplete annotated orthologs of human methyltransferase-like proteins (METTLs) in Drosophila cells and identified CG9666, the ortholog of human METTL5. We show that CG9666 is required for specific deposition of m6A on 18S ribosomal …

Epigenetic dysregulation in the developing Down syndrome cortex

2016

Using Illumina 450K arrays, 1.85% of all analyzed CpG sites were significantly hypermethylated and 0.31% hypomethylated in fetal Down syndrome (DS) cortex throughout the genome. The methylation changes on chromosome 21 appeared to be balanced between hypo- and hyper-methylation, whereas, consistent with prior reports, all other chromosomes showed 3–11 times more hyper- than hypo-methylated sites. Reduced NRSF/REST expression due to upregulation of DYRK1A (on chromosome 21q22.13) and methylation of REST binding sites during early developmental stages may contribute to this genome-wide excess of hypermethylated sites. Upregulation of DNMT3L (on chromosome 21q22.4) could lead to de novo methyl…

Relationship between apoptosis and survival molecules in human cumulus cells as markers of oocyte competence

2017

SummaryTo select from a single patient the best oocytes able to reach the blastocyst stage, we searched for valuable markers for oocytes competence. We evaluated the DNA fragmentation index (DFI) and the level of some survival molecules, such as AKT, pAKT and pERK1/2, in individual cumulus cell–oocyte complexes (COC). The study included normo-responder women. The average age of the patients was 34.3. DFI in cumulus cells was evaluated using the terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labelling (TUNEL) assayin situ. AKT, pAKT and pERK1/2 were measured by immunological assay and densitometric analysis of fluorescent signals using NIS-Elements BR 3.10 image software. Statisti…

Novel hereditary angioedema linked with a heparan sulfate 3-O-sulfotransferase 6 gene mutation

2020

Background Hereditary angioedema (HAE) is a potentially fatal disorder resulting in recurrent attacks of severe swelling. It may be associated with a genetic deficiency of functional C1 inhibitor or with normal C1 inhibitor (HAEnCI). In families with HAEnCI, HAE-linked mutations in the F12, PLG, KNG1, ANGPT1, or MYOF genes have been identified. In many families with HAEnCI the genetic cause of the disease is currently unknown. Objective The aim of this study was to identify a novel disease-linked mutation for HAEnCI. Methods The study methods comprised whole exome sequencing, Sanger sequencing analysis, pedigree analysis, bioinformatic analysis of the mutation, and biochemical analysis of p…

Antibodies to hepatitis B core antigen in blood donors screened for alanine aminotransferase level and hepatitis non-A, non-B in recipients.

1988

Four-hundred and seventeen patients undergoing open-heart surgery were followed for more than 9 months after transfusion. All 2270 blood units transfused had alanine aminotransferase levels less than or equal to 30 U/l. Blood units positive for antibodies to hepatitis B core antigen (anti-HBc) were more frequently associated with recipient hepatitis non-A, non-B (HNANB) (13.7%) than anti-HBc-negative units (4.2%) (p less than 0.001). The frequency of HNANB among recipients of at least 1 anti-HBc-positive blood unit (8/79, 10.1%) was fivefold greater than among recipients of exclusively anti-HBc-negative blood units (7/338, 2.1%) (p less than 0.01). In this study the exclusion of donors posi…