(Press-News.org) PITTSBURGH—The interior of a living cell is a crowded place, with proteins and other macromolecules packed tightly together. A team of scientists at Carnegie Mellon University has approximated this molecular crowding in an artificial cellular system and found that tight quarters help the process of gene expression, especially when other conditions are less than ideal.
As the researchers report in an advance online publication by the journal Nature Nanotechnology, these findings may help explain how cells have adapted to the phenomenon of molecular crowding, which has been preserved through evolution. And this understanding may guide synthetic biologists as they develop artificial cells that might someday be used for drug delivery, biofuel production and biosensors.
"These are baby steps we're taking in learning how to make artificial cells," said Cheemeng Tan, a Lane Postdoctoral Fellow and a Branco-Weiss Fellow in the Lane Center for Computational Biology, who led the study. Most studies of synthetic biological systems today employ solution-based chemistry, which does not involve molecular crowding. The findings of the CMU study and the lessons of evolution suggest that bioengineers will need to build crowding into artificial cells if synthetic genetic circuits are to function as they would in real cells.
The research team, which included Russell Schwartz, professor of biological sciences; Philip LeDuc, professor of mechanical engineering and biological sciences; Marcel Bruchez, professor of chemistry; and Saumya Saurabh, a Ph.D. student in chemistry, developed their artificial cellular system using molecular components from bacteriophage T7, a virus that infects bacteria that is often used as a model in synthetic biology.
To mimic the crowded intracellular environment, the researchers used various amounts of inert polymers to gauge the effects of different density levels.
Crowding in a cell isn't so different from a crowd of people, Tan said. If only a few people are in a room, it's easy for people to mingle, or even to become isolated. But in a crowded room where it's hard to move around, individuals will often tend to stay close to each other for extended periods. The same thing happens in a cell. If the intracellular space is crowded, binding between molecules increases.
Notably, the researchers found that the dense environments also made gene transcription less sensitive to environmental changes. When the researchers altered concentrations of magnesium, ammonium and spermidine – chemicals that modulate the stability and binding of macromolecules – they found higher perturbations of gene expression in low density environments than in high density environments.
"Artificial cellular systems have tremendous potential for applications in drug delivery, bioremediation and cellular computing," Tan said. "Our findings underscore how scientists could harness functioning mechanisms of natural cells to their advantage to control these synthetic cellular systems, as well as in hybrid systems that combine synthetic materials and natural cells."
INFORMATION:
This work was supported by grants from the National Institutes of Health and the National Science Foundation, as well as Tan's Lane Postdoctoral Fellowship and his Society in Science – Branco Weiss Fellowship. The Lane Center for Computational Biology is part of Carnegie Mellon's School of Computer Science.
About Carnegie Mellon University: Carnegie Mellon (http://www.cmu.edu) is a private, internationally ranked research university with programs in areas ranging from science, technology and business, to public policy, the humanities and the arts. More than 12,000 students in the university's seven schools and colleges benefit from a small student-to-faculty ratio and an education characterized by its focus on creating and implementing solutions for real problems, interdisciplinary collaboration and innovation. A global university, Carnegie Mellon has campuses in Pittsburgh, Pa., California's Silicon Valley and Qatar, and programs in Africa, Asia, Australia, Europe and Mexico. The university recently completed "Inspire Innovation: The Campaign for Carnegie Mellon University," exceeding its $1 billion goal to build its endowment, support faculty, students and innovative research, and enhance the physical campus with equipment and facility improvements. The campaign closed June 30, 2013.
END
Exceptional spatial ability at age 13 predicts creative and scholarly achievements over 30 years later, according to results from a new longitudinal study published in Psychological Science, a journal of the Association for Psychological Science.
The study, conducted by psychology researcher David Lubinski and colleagues at Vanderbilt University, provides evidence that early spatial ability — the skill required to mentally manipulate 2D and 3D objects — predicts the development of new knowledge, and especially innovation in science, technology, engineering, and mathematics ...
BOSTON – When Georgetown University neurologist R. Scott Turner, MD, PhD, began enrolling people with mild to moderate Alzheimer's disease into a nationwide study last year, he expected to find only a handful of participants with undiagnosed glucose intolerance, as all the patients were already under a doctor's care and those with known diabetes were excluded. But Turner says he was "shocked" by how many study participants were found to have pre-diabetes — a finding that is triggering important questions.
Turner's study examines resveratrol, a compound found in red grapes ...
CHICAGO, IL – Baseball players undergoing ulnar collateral ligament (UCL) surgery are able to return to the same or higher level of competition for an extended period of time, according to research presented today at the American Orthopaedic Society for Sports Medicine's (AOSSM) Annual Meeting in Chicago, IL.
"Previous studies showed successful return to play after UCL surgery, but we were also able to evaluate each athlete's career longevity and reason for retirement," commented lead author, Daryl C. Osbahr, MD of MedStar Union Memorial Hospital in Baltimore. "These ...
Alexandria, VA – One of the greatest controversies in science is what's underneath the Yellowstone supervolcano. The controversy surrounds a unique relationship between a mantle plume (like the one that powers Hawaiian volcanoes) and the subduction zone off the Washington-Oregon coast. Cutting-edge research using a common kitchen ingredient is explored in the latest issue of EARTH Magazine.
Recently published research explores this problem in 3-D, using a model created with corn syrup, fiberglass and a series of hydraulic pistons. What the scientists saw was a plume sliced ...
CHICAGO, IL – Athletes who didn't get enough sleep the night before undergoing baseline concussion testing didn't perform as well as expected, say researchers presenting their work today at the American Orthopaedic Society for Sports Medicine's (AOSSM) Annual Meeting in Chicago, IL.
"Our results indicate athletes sleeping less than 7 hours the night prior to baseline concussion testing did not do as well on 3 out of 4 ImPACT scores and showed more symptoms," said lead author, Jake McClure, MD from Vanderbilt University. "Because return-to-play decisions often hinge on ...
CHICAGO, IL – 40,000 high school football kids get a concussion every year, but contrary to equipment manufacturers' claims, the specific brand of helmet and helmet age were not associated with lower risk of concussion, say researchers presenting their work today at the American Orthopaedic Society for Sports Medicine's Annual Meeting in Chicago, IL.
"According to our research, lower risks of sustaining a sports-related concussion (SRC) and its severity were not improved based on a specific manufacturer. In addition, the SRC rates were similar for players wearing new ...
BOSTON -- Although women who survived childhood cancer face an increased risk of infertility, nearly two-thirds of those who tried unsuccessfully to become pregnant for at least a year eventually conceived, according to clinical researchers at Dana-Farber/Boston Children's Cancer and Blood Disorders Center and Brigham and Women's Hospital. This is comparable to the rate of eventual pregnancy among all clinically infertile women.
"Most women think that if they had cancer as a child, then they'll never have children. It turns out that many of them can get pregnant. It ...
TORONTO, ON – Males and females face different challenges in accessing treatment for neglected tropical diseases (NTDs), according to a new study from researchers at the University of Toronto Dalla Lana School of Public Health, Uganda Ministry of Health and Imperial College London. The study, published by PLOS Neglected Tropical Diseases on July 11, explores the role of gender in access to treatment in the Uganda National Neglected Tropical Disease Control Program.
NTDs are a group of parasitic, viral and bacterial diseases that affect at least a billion people worldwide. ...
Boulder, Colo., USA – Twenty-five new articles have been posted online ahead of print on Geology's website since 28 June. The science covers a gamut of topics, from microbial mats to super-eruptions; sand to monsoons; glaciers to sinkholes. All Geology articles go through a rigorous peer-review process prior to print. Geology is the highest rated journal for geoscience for the seventh year in a row, according to a 2012 Thomson Reuters survey.
Highlights are provided below. GEOLOGY articles published ahead of print can be accessed online at http://geology.gsapubs.org/content/early/recent. ...
NJIT Professor Michel Boufadel, is a co-author of a new expert report on the effects of the Deepwater Horizon (DWH) Mississippi Canyon-252 oil spill on ecosystem services in the Gulf of Mexico.
Entitled "An Ecosystem Services Approach to Assessing the Impacts of the Deepwater Horizon Oil Spill in the Gulf of Mexico," the report, published by the National Academy of Sciences, makes the case for how and why a more resilient Gulf of Mexico ecosystem needs to be developed. Recommendations include a plea to build an infrastructure to organize and integrate data. The ...
