Cytosine 59 methylation of CpG dinucleotides within and around genes exerts a major influence on transcription in many plants and animals (1–3). DNA methylation can be causal for transcriptional silencing (4–5) and targets the machinery necessary to assemble specialized chromatin enriched in deacetylated histones (6–8). Once established in somatic cells, CpG methylation patterns within the geno...

The levels of ribonucleotide reductase activity (measured as the conversion of 3H-cytosine monophosphate to 3HdCMP) in cell-free extracts of partially synchronized cultures of L cells were measured as the cells moved through the division cycle. A strict parallelism was found between the measured enzyme levels and the fractions of the population that were forming DNA. This relationship between e...

This paper reports the first array type chip for DNA methylation assay by electrochemiluminescence (ECL) detection. This was achieved using a small volume (141-nL) sample between two thin film electrodes that enabled us to observe an ECL emission derived from an anti methyl-cytosine antibody with a high signal-to-noise ratio. We performed a single methyl-cytosine measurement in DNA without the ...

A first synthesis of a new class of novel cytosine thioglycoside analogs from readily available starting materials has been described. The key step of this protocol is the formation of sodium pyrimidine-4-thiolate via condensation of N'-arylidene-2-cyanoacetohydrazides with sodium cyanocarbonimidodithioate salt, followed by coupling with halo sugars to give the corresponding cytosine thioglycos...

Many organisms expand the information content of their genome through enzymatic methylation of cytosine residues. Here we report the 2.8 A crystal structure of a bacterial DNA (cytosine-5)-methyltransferase (DCMtase), M. HaeIII, bound covalently to DNA. In this complex, the substrate cytosine is extruded from the DNA helix and inserted into the active site of the enzyme, as has been observed fo...

The DNA double helix, one of the most amazing and important self-assembled structures found in nature is dependendent on the interaction between the DNA base molecules: Adenine (A) and Thymine (T); and Cytosine (C) and Guanine (G). Recently there have been a number of Scanning Tunneling Microscope (STM) experiments on the gold (111) surface in which the DNA base molecules (Adenine (A), Cytosine...

Marrow specimens obtained from 23 patients with acute myelocytic leukemia were exposed to cytosine arabinoside and/or daunorubicin in vitro, and the effects of these agents on colony formation in vitro was determined. Thymidine suicide indices were determined as well, which permitted a distinction to be made between kinetic and metabolic resistance to cytosine arabinoside. The sensitivity of th...

1. When DNA is hydrolysed with formic acid for 30min. at 175 degrees and the hydrolysate is chromatographed on paper with propan-2-ol-2n-hydrochloric acid, in addition to expected ultraviolet-absorbing spots corresponding to guanine, adenine, cytosine and thymine, an ultraviolet-absorbing region with R(F) similar to that of uracil can be detected. Uracil was separated from this region and ident...

In this work, we developed a label-free, homogeneous surface-enhanced Raman-scattering (SERS) platform for the rapid, simple and sensitive detection of Ag(+) by using the unmodified gold nanoparticles (AuNPs). It utilizes the different absorption properties of single-strand DNA (ssDNA) and double-strand DNA (dsDNA) on citrate-coated AuNPs and specific interactions between Ag(+) and cytosine-cyt...