Susceptibilities to snake venom 5'-nucleotidase (EC 3.1.3.5) have been evaluated for several 8-substituted analogues of 5'-GMP with varying populations of syn/anti conformations about the glycosidic bond. Improved syntheses of some of these are described, including direct chlorination of 5'-GMP to give 8-chloro-5'-GMP, a procedure which should be applicable to other purine nucleotides. The conf...

5-Formylcytidine (f(5)C), a previously discovered natural nucleotide in the mitochondrial tRNA of many species including human, has been recently detected as the oxidative product of 5-methylcytidine (m(5)C) through 5-hydroxymethylcytidine (hm(5)C) in total RNA of mammalian cells. The discovery indicated that these cytosine derivatives in RNA might also play important epigenetic roles similar a...

The thymine analog 5-chlorouridine, first reported in the 1950s as anti-tumor agent, is known as an effective mutagen, clastogen and toxicant as well as an effective inducer of sister-chromatid exchange. Recently, the first microorganism with a chemically different genome was reported; the selected Escherichia coli strain relies on the four building blocks 5-chloro-2'-deoxyuridine (ClU), A, C a...

PURPOSE Aging is believed to affect epigenetic marking of brain DNA with 5-methylcytosine (5mC) and possibly via the 5mC to 5-hydroxymethylcytosine (5hmC) conversion by TET (ten-eleven translocation) enzymes. We investigated the impact of aging on hippocampal DNA 5-hydroxymethylation including in the sequence of aging-susceptible 5-lipoxygenase (5-LOX) gene. METHODS Hippocampal samples were o...

Serotonin (5-HT) is one of the major monoamines in the brain. It is also found in the retina, a part of the brain, where a subgroup of amacrine cells are considered to be the sole retinal source of 5-HT. The data, obtained so far, about the serotonin receptors’ function are contradictory. Therefore, our aim was to study the distribution of the 5-HT synthesizing neurons and the serotonin recepto...