Regulation of nucleosome stability as a mediator of chromatin function

Interactions among regulatory proteins, enzymes and DNA are required to use the information encoded in genomes. In eukaryotes, the location and timing of interactions between these proteins and DNA is determined in large part by whether DNA at a given locus is packaged into a nucleosome. Given the central role of nucleosome formation in regulating genome function, many mechanisms have evolved to control nucleosome stability at loci across the genome. New conclusions about the role of the DNA sequence itself in the regulation of nucleosome stability have come from two new types of experiment: high-resolution mapping of in vivo nucleosome occupancy on a genomic scale; and in vivo versus in vitro comparisons of nucleosome stability on natural DNA templates. These new types of data raise intriguing questions about the evolutionary constraints on DNA sequence with regard to nucleosome formation, and at long last might enable the derivation of DNA sequence-based rules that produce reliable predictions of nucleosome behavior

Sarcopenia: its assessment, etiology, pathogenesis, consequences and future

Sarcopenia is a loss of muscle protein mass and loss of muscle function. It occurs with increasing age, being a major component in the development of frailty. Current knowledge on its assessment, etiology, pathogenesis, consequences and future perspectives are reported in the present review. On-going and future clinical trials on sarcopenia may radically change our preventive and therapeutic approaches of mobility disability in older peopleY. Rolland, S. Czerwinski, G. Abellan Van Kan, J.E. Morley, M. Cesari, G. Onder, J. Woo, R. Baumgartner, F. Pillard, Y. Boirie, W.M.C. Chumlea, B. Vella

An integrated encyclopedia of DNA elements in the human genome.

The human genome encodes the blueprint of life, but the function of the vast majority of its nearly three billion bases is unknown. The Encyclopedia of DNA Elements (ENCODE) project has systematically mapped regions of transcription, transcription factor association, chromatin structure and histone modification. These data enabled us to assign biochemical functions for 80% of the genome, in particular outside of the well-studied protein-coding regions. Many discovered candidate regulatory elements are physically associated with one another and with expressed genes, providing new insights into the mechanisms of gene regulation. The newly identified elements also show a statistical correspondence to sequence variants linked to human disease, and can thereby guide interpretation of this variation. Overall, the project provides new insights into the organization and regulation of our genes and genome, and is an expansive resource of functional annotations for biomedical research