Search results for " telomeres"
showing 8 items of 8 documents
Understanding ageing: Biomedical and bioengineering approaches, the immunologic view
2008
Abstract During the past century, humans have gained more years of average life expectancy than in the last 10,000 years; we are now living in a rapidly ageing world. The sharp rise in life expectancy, coupled to a steady decline in birth rates in all developed countries, has led to an unprecedented demographic revolution characterized by an explosive growth in the number and proportion of older people. Ageing is a complex process that negatively impacts the development of the immune system and its ability to function. Progressive changes in the T and B cell systems over the life span have a major impact on the capacity to respond to immune challenge. These cumulative age-associated changes…
Telomeres as a molecular marker of male infertility
2018
In recent years, male infertility has become a growing social problem. Standard diagnostic procedures, based on assessing seminological parameters, are often insufficient to explain the causes of male infertility. Because of this, new markers with better clinical application are being sought. One of the promising markers seems to be an assessment of telomere length of sperm. Sperm telomeres, in contrast to somatic cells, are elongated as men age. The results of some studies suggest that telomere length may be relevant in the case of fertilization and normal embryo development. Literature reports indicate that there is a correlation between telomere length of sperm and abnormal sperm paramet…
Acetylated nucleosome assembly on telomeric DNAs
2003
Abstract The role of histone N-terminal domains on the thermodynamic stability of nucleosomes assembled on several different telomeric DNAs as well as on ‘average’ sequence DNA and on strong nucleosome positioning sequences, has been studied by competitive reconstitution. We find that histone tails hyperacetylation favors nucleosome formation, in a similar extent for all the examined sequences. On the contrary, removal of histone terminal domains by selective trypsinization causes a decrease of nucleosome stability which is smaller for telomeres compared to the other sequences examined, suggesting that telomeric sequences have only minor interactions with histone tails. Micrococcal nuclease…
The histone deacetylase Rpd3 regulates telomeric heterochromatin structure of polytene chromosomes
2010
From cellular senescence to age-associated diseases: miRNAs as tools and targets for healthy ageing
2017
miRNAs are the most abundant RNA species to be found in cell-free blood, encapsulated within microvesicles or bound to proteins. miRNAs play essential roles in the regulation of various biological processes. Moreover, specific changes in miRNA transcription levels or miRNA secretory levels have been linked to the development and progression of certain age-related diseases. So, they might be an ideal target for modulating healthy ageing
UbcD1: from telomere capping to global chromatin regulation
2012
Human DNA Telomeres in Presence of Oxidative Lesions: The Crucial Role of Electrostatic Interactions on the Stability of Guanine Quadruplexes
2019
By using all atom molecular dynamics simulations, we studied the behavior of human DNA telomere sequences in guanine quadruplex (G4) conformation and in the presence of oxidative lesions, namely abasic sites. In particular, we evidenced that while removing one guanine base induces a significant alteration and destabilization of the involved leaflet, human telomere oligomers tend, in most cases, to maintain at least a partial quadruplex structure, eventually by replacing the empty site with undamaged guanines of different leaflets. This study shows that (i) the disruption of the quadruplex leaflets induces the release of at least one of the potassium cations embedded in the quadruplex channe…