Navigation Links
Combined molecular study techniques reveal more about DNA proteins

CHAMPAIGN, Ill. Illinois researchers have combined two molecular imaging technologies to create an instrument with incredible sensitivity that provides new, detailed insight into dynamic molecular processes.

Physics professors Taekjip Ha and Yann Chemla and combined their expertise in single-molecule biophysics fluorescence microscopy and optical traps, respectively to study binding and unbinding of individual DNA segments to a larger strand. They and their joint postdoctoral researcher Matthew Comstock detail their technique in a paper published in the Feb. 20 online edition of Nature Methods.

Both professors have particularly studied proteins and enzymes that regulate DNA, such as the enzyme helicase that unwinds DNA for duplication or transcription to RNA. Fluorescent microscopy techniques allow researchers to observe proteins as they conform and move, but often lack the spatial range to track the protein's motion over distance.

Optical traps, meanwhile, enable researchers to study a protein's translocation, but not its conformation. Chemla compares traditional optical traps to fishing. A single molecule of DNA is tethered between two attachment points, and the activity of a protein bound to it is only inferred from how it tugs on the tether, much like a fish at the end of a line. This can reveal a lot about a protein's activity and motion, but the technique has glaring limitations as well. For example, it is difficult to know how many proteins or the types of proteins that are involved.

"Also, these proteins may do all sorts of things beyond tugging on our line that we may not be sensitive to," Chemla said. "Fluorescence allows you to have an additional readout to actually see these things, and the key is that we can now measure them simultaneously. This work was a real synthesis of the expertise of two groups at the Center for the Physics of Living Cells at the U. of I."

The combination allows Chemla, Ha and their group to measure both a protein's motion sensitive to translocation as small as one DNA base pair, a distance of only a few angstroms and also conformational changes as it acts. This can reveal details about its mechanism that would not have been accessible before.

"It was a major technical challenge, but the final product is a one-of-a-kind instrument with unique capabilities," Chemla said. "It's like taking a rudimentary, real-time 'movie' of what individual molecules are doing."


Contact: Liz Ahlberg
University of Illinois at Urbana-Champaign

Related biology news :

1. Newborn screening increases survival outcome for patients with severe combined immunodeficiency
2. AOptix Technologies to Show Combined Biometric Face and Iris Capture System at Biometrics Consortium Conference
3. Reading food labels, combined with exercise, can lead to weight loss
4. Combined stem cell-gene therapy approach cures human genetic disease in vitro
5. A combined tooth-venom arsenal revealed as key to Komodo dragons hunting strategy
6. Fingerprints match molecular simulations with reality
7. Designing new molecular tools to study the life and death of a cancer cell
8. Molecular network influences development of chronic lymphocytic leukemia
9. Polymer membranes with molecular-sized channels that assemble themselves
10. Molecular medicine could avert predicted catastrophic vision loss in the aged
11. New book highlights the cellular and molecular determinants of brain wiring
Post Your Comments:
(Date:9/28/2015)... , Sept. 28, 2015 CLEAR, ... that its expedited traveler service is coming ... transforms travel, bringing a frictionless experience, serious ... "CLEAR offers our travelers an ... service," said Jim Smith , Executive ...
(Date:9/28/2015)... PUNE, India , September 28, 2015 ... Recognition Market by Component (Hardware & Software), Product (Scanner & ... Immigration, Military & Defense, & Others) & Geography Global ... Market is expected to reach USD 3627.90 Million by ... 2020. Browse 65 market data T ...
(Date:9/24/2015)... NEW YORK , Sept. 24, 2015  EyeLock ... will be showcasing its award winning and latest technology ... Anaheim, California . EyeLock,s ... and security with unmatched biometric accuracy, making it the ... DNA.   EyeLock,s platform uses video technology to deliver a ...
Breaking Biology News(10 mins):
(Date:10/9/2015)... On October 8, the Honorable Doris O. ... recognizing the third annual International Plasma Awareness Week (IPAW), ... the Plasma Protein Therapeutics Association (PPTA) and ... , Raise global awareness about plasma donation , ... improving lives , Increase understanding about lifesaving plasma ...
(Date:10/9/2015)... ROCKVILLE, Md. , Oct. 9, 2015 /PRNewswire/ ... developing next generation vaccines based on the LAMP-vax ... an exclusive worldwide licensing agreement with Astellas Pharma ... prevention of any and all allergic diseases in ... will receive an upfront payment of $300 million ...
(Date:10/9/2015)...  Pulmatrix, Inc., (NASDAQ: PULM ) will be webcasting ... th Annual BIO Investor Forum on Tuesday, ... --> th Annual BIO Investor Forum ... pm EDT). --> Pulmatrix will be presenting ... on Thursday, October 15, 2015 at 8:30 am EDT. Additionally, ...
(Date:10/9/2015)... ... October 09, 2015 , ... Leading microbial genomics startup uBiome today launched the ... relationship between weight management and the microbiome. The study uses the ResearchKit framework, designed ... iPhone app. , The uBiome app is available as a free download from the ...
Breaking Biology Technology: