The results of their study are reported in the journal Nature Communications.
Cholesterol's role in heart disease has given it a bad reputation. But inside the thin membrane of a cell, the tight regulation of cholesterol at high levels (30 to 40 percent) suggests that it plays an important role in cellular processes, says Wonhwa Cho, professor of chemistry at the University of Illinois at Chicago and principal investigator on the study.
Cho and colleagues had previously found evidence that cholesterol was directly interacting with many proteins found in the interior of the cell. The interaction seemed necessary for the proper functioning of these proteins.
"This was quite a surprising finding," said Cho, because cholesterol resides within the membrane, sandwiched between its inner and outer face. Cell biologists had thought it could only interact with other biomolecules within the membrane.
In the new study, Cho and his colleagues showed how cholesterol interacts with a scaffolding protein, one of a class of proteins that plays an important role in cell signaling. The researchers showed that cholesterol binds to a region on the protein molecule where one of its signaling partners also binds -- and that disrupting cholesterol binding to the protein makes it unable to activate its partner.
The researchers describe in detail how the protein hooks onto and reaches inside the membrane to find and bind cholesterol.
Cho believes that this strategy for interacting with cholesterol may be used by many interior cellular proteins and offers an insight into what is known about the importance of cholesterol to well-functioning cells.
Much of the existing data on the cholesterol-related regulation of cellular processes had been difficult to interpret, he said.
"This is a major finding that will help people understand how cholesterol may regulate other cellular processes," Cho said.
Ren Sheng, graduate student in chemistry at UIC, was first author of the paper. Other authors are Yong Chen, Ewa Stec, Heather Melowic, Nichole Blatner and Moe Tun, all of the UIC chemistry department; Morten Kallberg and Hui Lu of the UIC bioengineering department; Heon Yung Gee, Yonjung Kim and Min Goo Lee of the Yonse University College of Medicine in Seoul; Takahiro Fujiwara and Akhiro Kusumi of Kyoto University in Japan; and Ji Hye Hong and Kwang Pyo Kim of Konkuk University in Seoul.
This study was supported by the Chicago Biomedical Consortium with the support of the Searle Funds at the Chicago Community Trust; National Institutes of Health grant GM68849; the World Class University program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology; and a grant from the National Project for Personalized Medicine, part of the Korea Health 21 R&D Project of the Korean Ministry of Health and Welfare.
UIC ranks among the nation's leading research universities and is Chicago's largest university with 27,000 students, 12,000 faculty and staff, 15 colleges and the state's major public medical center. A hallmark of the campus is the Great Cities Commitment, through which UIC faculty, students and staff engage with community, corporate, foundation and government partners in hundreds of programs to improve the quality of life in metropolitan areas around the world. For more information about UIC, please visit www.uic.edu.
NOTE: Please refer to the institution as the University of Illinois at Chicago on first reference and UIC on second reference. "University of Illinois" and "U. of I." are often assumed to refer to our sister campus in Urbana-Champaign.
Jeanne Galatzer-Levy | EurekAlert!
Researchers identify new way to unmask melanoma cells to the immune system
17.01.2018 | Duke University Medical Center
Study advances gene therapy for glaucoma
17.01.2018 | University of Wisconsin-Madison
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
18.01.2018 | Medical Engineering
18.01.2018 | Ecology, The Environment and Conservation
17.01.2018 | Ecology, The Environment and Conservation