histones

Man and mouse share genome structures

... a working chromosome. Chemical tags placed on the histones alter the way chromatin is organized, thus allowin... For example, proteins that place methyl groups on histones can, when mutated, cause leukemia. Bernstein hopes to apply the new technology to characterize chrom...

Enzyme shown to help protect genomic stability

...ion is repressed. When the coils of DNA around the histones are loosened or the histone molecules are altered,...hich Ubp10 contributes. Enzymatic modifications to histones control DNA activation or silencing through the addition or removal of acetyl, methyl, and ubiquitin...

Protein helps regulate the genes of embryonic stem cells

...tein. The prevailing model is that methylation on histones serves as a docking site for proteins that "read" ...ification, any given gene associated with modified histones is marked to be turned on or off. In the study, eed is the first protein shown to be required for t...

Novel enzyme offers new look at gene regulation

... histone had been regarded as irreversible. "That histones can become methylated has been known for over thre...ated with DNA, even slight chemical alterations of histones can have profound effects on nearby genes. Depending on the precise location and how many methyl gro...

New mechanism for essential genome-wide gene silencing identified

...entists showed that a protein called SUMO binds to histones and acts to repress transcription of genes, and it... ago. "In our experiments, we saw SUMO binding to histones across the genome, suggesting that if this mechanism went wrong, it could have a dramatic effect," s...

Pathway toward gene silencing described in plants

... the chromatin remodeler DRD1 presumably bulldozes histones and other proteins out of the way to make the DNA accessible for methylation by the de novo cytosine methyltransferase, DRM2. A paradoxical aspect of the pathway is that siRNAs direct DNA methylation but DNA methylation is also required for the pro...

Loosen up, DNA: Leukemia gene changes genetic packaging

... is spooled up very tightly around proteins called histones in the nucleus of nearly every cell in our bodies. The whole structure, called chromatin, looks much like a narrow thread wound tightly around a stack of tuna cans. While there are genes aplenty in every cell, not all our DNA is equally accessible to...

University of Minnesota researchers take new look at cellular suicide

...aging its functions. "In the past, people thought histones were just for packaging DNA," said Dong, who studied a histone named H2AX. "People believe H2AX plays a role in DNA repair. But we find that if DNA can't be repaired, the cell undergoes apoptosis. The histone H2AX is probably important for both apopt...

Researchers find protein that silences genes

...ty. It can remove the acetyl groups from multiple histones and from multiple lysines of those histones" said ...ehind the silencing involves both modifications of histones and changes in DNA methylation, and that HDA6 affects both. Circular pathway to silence "Somehow...

Regulating the nuclear architecture of the cell

... a set of proteins known as histones; four similar histones join together to form a cylindrical spool around w... codes for proteins that chemically modify certain histones in the nucleosomes. Su(var)3-9 proteins attach methyl groups to the histone labeled H3 at its ni...

Beyond the DNA: Chemical signatures reveal genetic switches in the genome

...lls and discovered distinct signatures of modified histones that correspond to known promoters and enhancers. ...s that it utilizes a chemical signature present on histones but not DNA. Existing methods to predict enhancers rely on the DNA sequence alone, but these are ina...

Revealing the machinery underlying the 'plastic' juvenile brain

...telltale chemical alterations in substances called histones that were not triggered in the adult brains. Such histones are protein components of the spools around which DNA winds in chromosomes, and alterations of histo...