The idea that RNA (ribonucleic acid) is involved in activating and inhibiting genes is relatively new, and it has been unclear how RNA strands might regulate the process.
Genes are segments of DNA housed in the nucleus of every cell, and they carry instructions for making proteins. Faulty or mutated genes lead to malfunctioning, missing or overabundant proteins, and any of those conditions can result in disease. Scientists seek to understand the mechanisms by which genes are activated, or expressed, and turned off in order to get a clearer picture of basic cell biology and also to develop medical therapies that affect gene expression.
In previous studies, Dr. Corey and Dr. Bethany Janowski, assistant professor of pharmacology at UT Southwestern and a senior author of the current study, have shown that tiny strands of RNA can be used to activate certain genes in cultured cancer cells. Using strands of RNA that they manufactured in the lab, the researchers showed that the strands regulate gene expression by somehow perturbing a delicate mixture of proteins that surround DNA and control whether or not genes are activated.
Until now, however, it was not clear exactly how the synthetic RNA strands affected that mix of regulating proteins.
In the current study, also carried out in cancer cell cultures, the UT Southwestern research team discovered an unexpected target for the manufactured RNA. The RNA did not home in on the gene itself, but rather on another type of RNA produced by the cell, a so-called noncoding RNA transcript. This type of RNA is found in association with the promoter regions that occur in front of the gene. Promoter regions, when activated, act essentially as a “start” command for turning on genes.
The researchers found that their man-made RNA strand bound to the RNA transcript, which then recruited certain proteins to form an RNA-protein complex. The whole complex then bound to the promoter region, an action that could then either activate or inhibit gene expression.
“Involvement of RNA at a gene promoter is a new concept, potentially a big new concept,” Dr. Janowski said. “Interactions at gene promoters are critical for understanding disease, and our results bring a new dimension to understanding how genes can be regulated.”
Until recently, many scientists believed that proteins alone control gene expression at promoters, but Drs. Corey and Janowski’s results suggest that this assumption is not necessarily true.
“By demonstrating how small RNAs can be used to recruit proteins to gene promoters, we have provided further evidence that this phenomenon should be in the mainstream of science,” Dr. Corey said.
Although using synthetic RNA to regulate gene expression and possibly treat disease in humans is still in the future, Dr. Corey noted that the type of man-made RNA molecules employed by the UT Southwestern team are already being used in human clinical trials, so progress toward the development of gene-regulating drugs could move quickly.
Other researchers from UT Southwestern involved in the research were lead author and student research assistant Jacob Schwartz; student research assistant Scott Younger; and research associate Ngoc-Bich Nguyen. Researchers from the University of Western Ontario and ISIS Pharmaceuticals also participated.
The research was supported by the National Institutes of Health and the Welch Foundation.
Amanda Siegfried | EurekAlert!
First time-lapse footage of cell activity during limb regeneration
25.10.2016 | eLife
Phenotype at the push of a button
25.10.2016 | Institut für Pflanzenbiochemie
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
25.10.2016 | Earth Sciences
25.10.2016 | Life Sciences
25.10.2016 | Earth Sciences