With the sequence of the human genome largely in hand and the majority of genes now available for study, scientists have increasingly turned their attention to better understanding the process of gene regulation. How is a gene turned on? How is a gene turned off? Estimates are that only one in ten genes is active in a given cell at a given time, so these questions are biologically significant. And in many ways, health turns on the appropriate and reliable control of genes. An array of disease conditions can arise if normal gene regulation is perturbed for any reason.
In the case of gene activation, past studies have revealed that specific molecular additions to DNA-packaging proteins called histones are critical to the process. A number of histones are generally involved in the packaging of a single gene, and the picture had emerged of different enzymes adding different molecular groups to different histones to achieve a series of small changes with the collective outcome of turning the gene on. In essence, additions to histones were accumulated until the "on" state was reached.
Now, a new study by researchers at The Wistar Institute reveals the gene-activation process through these molecular modifications to be more dynamic than had been appreciated previously. Specifically, the teams experiments show that, within the process of turning a gene on, the addition of a molecule called ubiquitin is required and, at a different stage of activation, the removal of ubiquitin is also necessary. A sequence of modifications is therefore involved – including some that may be reversible, it is now clear. The picture of certain molecular groups being added to histones until the cumulative changes result in gene activation now appears inadequate to explain the process. Instead, a new view that places greater emphasis on the specific order of molecular events within the process of gene activation targeting the histones now seems more informative.
Franklin Hoke | EurekAlert!
Carefully crafted light pulses control neuron activity
20.11.2017 | University of Illinois at Urbana-Champaign
Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
20.11.2017 | Earth Sciences
20.11.2017 | Physics and Astronomy
17.11.2017 | Physics and Astronomy