In research published in the April 30th edition of Cell, a team of Whitehead Institute researchers describes a pausing step in the transcription process that serves to regulate expression of as many as 80% of the genes in mammalian cells.
Scientists have long known that DNA-binding transcription factors recruit the RNA polymerase Pol II (which prompts copying of DNA into mRNA protein codes) to promoters in order to kick off the transcription process. Now researchers in the lab of Whitehead Member Richard Young have found that additional factors recruited to the promoters serve to stop transcription in its tracks shortly after it's begun.
"It's like the engine's running, but the transmission is not engaged on that transcription apparatus," says Young, who is also a professor of biology at MIT. "You need something to engage that transmission."
It turns out that for a surprisingly large number of genes in embryonic stem cells, that "something" is the transcription factor c-Myc. This so-called pause release role for c-Myc is significant, as many of c-Myc's targets are genes in highly proliferative cells. Over-expression of c-Myc is a hallmark of a number of tumors, and it now appears that c-Myc's ability to release transcriptional pausing is linked with the hyper-proliferation that is characteristic of cancer cells.
"Our findings provide the molecular basis for loss of proliferation control in some cancers," says Peter Rahl, a postdoctoral researcher in Young's lab and first author of the Cell paper.
Armed with this new understanding of c-Myc's role in controlling proliferation genes, Young and his colleagues have embarked on a search for drugs that could interrupt c-Myc's pause-release activity in tumors where it's over-expressed.
"Clearly, cancer cells are able to exploit mechanisms that normally operate in embryonic stem cells," says Young, "so I expect further understanding of embryonic stem cell control mechanisms will give us additional insights into human disease mechanisms."
This research was supported by the National Institutes of Health (NIH) and National Cancer Institute (NCI).
Written by Nicole Giese
Richard Young's primary affiliation is with Whitehead Institute for Biomedical Research, where his laboratory is located and all his research is conducted. He is also a professor of biology at Massachusetts Institute of Technology.Full Citation:
Nicole Giese | EurekAlert!
Molecular microscopy illuminates molecular motor motion
26.07.2017 | Penn State
New virus discovered in migratory bird in Rio Grande do Sul, Brazil
26.07.2017 | Fundação de Amparo à Pesquisa do Estado de São Paulo
Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers
Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...
Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.
At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...
3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects
A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...
Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.
For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...
What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.
To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...
26.07.2017 | Event News
21.07.2017 | Event News
19.07.2017 | Event News
26.07.2017 | Physics and Astronomy
26.07.2017 | Life Sciences
26.07.2017 | Earth Sciences