Navigation Links
Mechanical forces could affect gene expression
Date:2/2/2010

ANN ARBOR, Mich.---University of Michigan researchers have shown that tension on DNA molecules can affect gene expression---the process at the heart of biological function that tells a cell what to do.

Scientists understand the chemistry involved in gene expression, but they know little about the physics. The U-M group is believed to be the first to actually demonstrate a mechanical effect at work in this process. Their paper is published in the current edition of Physical Review Letters.

"We have shown that small forces can control the machinery that turns genes on and off. There's more to gene regulation than biochemistry. We have to look at mechanics too," said Jens-Christian Meiners, associate professor in the Department of Physics and director of the biophysics program.

A better understanding of how cells regulate themselves could lead to new insights into how the process could fail and lead to disease.

"When cells start to misinterpret regulatory signals, cardiac disease, birth defects, and cancer can result. In fact, mechanical signals have been implicated as a culprit in a variety of pathologies," said Joshua Milstein, a research fellow in the Department of Physics.

To perform their experiment, the scientists used custom "optical tweezers," or lasers, to pull on the ends of bacterial DNA strands with 200 femtonewtons of force, said Yih-Fan Chen, a doctoral student in the Department of Biomedical Engineering. Chen designed and built the tweezers.

The force they used corresponds roughly to the weight of one-billionth of a grain of rice.

In segments of DNA that were tethered to a microscope slide, the scientists observed a 10-fold decrease in the rate at which the strands looped in on themselves.

DNA looping prevents genes within the loops from being expressed. A common mechanism for gene regulation, it also occurs in complex organisms including humans. Specialized proteins act as buckles to connect distant points on the DNA to form the loops. That's the chemistry part. The challenge for physics is to understand how the DNA bends so those distant points can come together.

While this experiment was performed on free DNA, the scientists say forces as much as 100 times stronger are regularly created inside cells as contents shift and buffet each other.

"If we can basically shut this process down with the tiniest force, how could all these larger forces not have an impact on gene expression?" Milstein said.

Meiners and his team are striving for a quantitative understanding of this biological process. He likens the current state of our understanding of gene expression to a diagram. He is searching for equations, and these results begin to provide that.

"We can tell you how long you'll have to wait for a DNA loop to form based on how much force you apply to the DNA," Meiners said. "We're one step closer to understanding cells quantitatively."


'/>"/>

Contact: Nicole Casal Moore
ncmoore@umich.edu
734-647-1838
University of Michigan
Source:Eurekalert

Related medicine news :

1. Mechanical ventilation for patients with lung damage dont always work as planned
2. Improved robotic hand captures mechanical engineering top award
3. Data Show Long-Term Mechanical Integrity of MitraClip(R) and Complete Healing Following Implantation of the Device for Mitral Valve Repair
4. Reportlinker Adds Mechanical Ventilators Report
5. Pharmacomechanical Thrombectomy Procedure Adoption to Accelerate Due to More Aggressive Treatment of Deep Vein Thrombosis, According to Millennium Research Group
6. First heart patients implanted with next-generation mechanical heart pump
7. ATS Medical Announces Regulatory Approval of the ATS Open Pivot AP360 Mechanical Heart Valve in Japan
8. Physical therapists test mechanical arm to help patients recover from stroke, traumatic brain injury
9. FDA approves HeartMate II mechanical heart pump for heart-failure patients
10. New research for mechanical support devices in pediatrics to be released at ISHLT
11. ATS Medical Receives FDA Approval for AP360 Mechanical Heart Valve
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/27/2017)... ... 2017 , ... Most us are familiar with the sound of occasional popping ... Osteoarthritis Initiative shows that certain people who experience consistent joint popping, grating and ... doctors the opportunity to treat patients before the problem becomes pronounced, potentially hedging off ...
(Date:5/26/2017)... VA (PRWEB) , ... May 26, 2017 , ... ... pleased to announce a new educational seminar to focus on current legislative activity ... News(LEARN) seminar will begin at 1 p.m. Sunday, Sept. 10, and will continue ...
(Date:5/26/2017)... ... May 26, 2017 , ... Boar’s Head Brand®, ... recipes for Memorial Day entertaining that are sure to satisfy your guests’ flavor ... sliced meats and cheeses featured in these refreshingly balanced recipes are packed with ...
(Date:5/26/2017)... ... May 26, 2017 , ... Yisrayl Hawkins, Pastor and Overseer at The House ... focusing on the Peace Agreements being discussed by President Donald Trump and the rest ... to try to speed up peace talks in the continuous battle between Israel and ...
(Date:5/26/2017)... ... ... “When the Stars Lead Home”: a poignant story of loss, determination, and perseverance. ... an avid reader who lives in the Pacific Northwest with her husband, daughter, two ... Camp. She couldn’t be more grateful. , Twelve-year old Tizzy could not believe how ...
Breaking Medicine News(10 mins):
(Date:5/6/2017)... , May 5, 2017   Provista , a proven ... than 200,000 customers, today announced Jim Cunniff as ... of executive and business experience to Provista, including most recently ... in California . He assumed his new ... is a great fit for Provista," says Jody Hatcher ...
(Date:5/4/2017)... Tenn. , May 4, 2017  A ... Infection Control, Ultraviolet-C light as a ... Tru-D SmartUVC,s ability to reduce bioburden on anesthesia ... bioburden reduction on high-touch, complex medical equipment surfaces ... surgical infections. "This study further validates ...
(Date:5/4/2017)... May 4, 2017  A new tight-tolerance microextrusion ... other highly-engineered materials, is being launched by Natvar, ... been developed in recent years to service a ... surgical applications. More expensive materials such as glass ... tubing due to their ability to consistently hold ...
Breaking Medicine Technology: