Their research is in a study published today (Feb.8, 2008) in the journal Science.
"This finding was unexpected -- especially since it entails a broad distribution of PARP-1 across the human genome and a strong correlation of the protein binding with genes being turned on," said W. Lee Kraus, Cornell associate professor in molecular biology and the corresponding author in the published study. Kraus has a dual appointment at Cornell's Weill Medical College in New York City. "Our research won't necessarily find cures for human diseases, but it provides molecular insight into the regulation of gene expression that will gives us clues where to look next."
Kraus explains that PARP-1 and another genome-binding protein called histone H1 compete for binding to gene "promoters" (the on-off switches for genes) and, as such, act as part of a control panel for the human genome. H1 puts genes in an "off" position and PARP-1 turns them "on." The new study, said Kraus, shows that for a surprising number genes, the PARP-1 protein is present and histone H1 is not, helping to keep those genes turned on.
When human cells are exposed to physiological signals, such as hormones, or to stress signals, such as metabolic shock or DNA damage caused by agents like ultra-violet (UV) light, the cells take action. One of the cellular responses is the production of NAD (nicotinamide adenine dinucleotide), a metabolic communication signal. NAD promotes the removal of PARP from the genome and alters PARP-1's ability to keep genes on, the scientists have found.
Knowing where this component of the genome's control panel -- the PARP-1 protein -- is located, scientists can better understand the effects of synthetic chemical inhibitors of PARP-1 activity, which are being explored for the treatment of human diseases including stroke, heart disease and cancer. Thus, conceivably, when a patient is having stroke, it may one day be possible to use PARP-1 inhibitors as part of stroke therapy, or one day play a role in targeting cancer, says Kraus.
"Think of PARP-1 as a key regulator of gene expression in response to normal signals and harmful stresses," said Kraus. "If you could control most of the traffic lights in a city's street grid with one hand, this is analogous to controlling gene expression across the genome with PARP-1. Under really adverse conditions, you can set all the lights to stop."
Blaine Friedlander | EurekAlert!
The birth of a new protein
20.10.2017 | University of Arizona
Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research