Navigation Links
Training cells to perform Boolean functions? It's logical
Date:5/31/2012

Johns Hopkins scientists have engineered cells that behave like AND and OR Boolean logic gates, producing an output based on one or more unique inputs. This feat, published in the May issue of Nature Chemical Biology, could eventually help researchers create computers that use cells as tiny circuits.

Study leader Takanari Inoue, Ph.D., an assistant professor in the Department of Cell Biology and member of the Institute of Basic Biomedical Sciences' Center for Cell Dynamics at the Johns Hopkins University School of Medicine, explains that many researchers are striving to mimic devices in everyday use by engineering new qualities into biological materials, including biomolecules and cells. Several of those engaged in this relatively new field, known as synthetic biology, have tried to create biological computers.

At the heart of both the biological and the more everyday silicon-based variety of computers are Boolean logic gates, which produce responses that vary depending on what type and how many inputs they receive. For example, AND gates need two unique inputs to generate an output. In contrast, OR gates generate an output based on whether they receive one input, or another, or both.

Inoue says that previous research has shown some success in generating logic gates based on biomolecules in test tubes or petri dishes. However, he adds, developing logic gates using whole cells has proven significantly trickier. Most previous efforts have taken advantage of cells' transcriptional machinery the cellular processes that read genes to create proteins to generate an output signal. But transcription can be a slow process, taking from minutes to days to produce the desired response.

"People like to have speedy computation," Inoue says. "We were hoping to achieve computation in cells on the order of seconds, which is significantly faster than what people have achieved thus far."

To accomplish their goal, the researchers used a technique called chemically inducible dimerization, or CID. This tool takes advantage of natural biological mechanisms that bring together two proteins into a complex in the presence of a chemical.

Since AND and OR gates generate a response based on two different inputs, either together or separately, the researchers needed two different CID systems that didn't compete or overlap with each other. They relied on one system that's been studied for years, which brings two proteins, called FRB and FKBP, together in the presence of a drug called rapamycin. Rapamycin comes from bacteria, and FRB and FKBP come from animals.

In addition, they used a second CID system that brings together two other proteins, known as GID1 and GAI, in the presence of a plant hormone called gibberellin. Since this system is native to plants, the gibberellin-based system doesn't compete with the rapamycin-based one, Inoue explains.

The researchers engineered mammalian cells that produce all four of the requisite proteins, as well as a response when the right two proteins came together. When either FRB and FKBP or GID1 and GAI linked up, the cell's membrane developed ruffles easily visible under a microscope.

To create the OR gate, FRB and GAI were bound together at the cell membrane, while FKBP and GID1 were bound together floating freely in the cell. Adding either rapamycin, gibberellin, or both to cells brought the freely floating complex to the one at the cellular membrane, linking up the matching proteins and triggering the output signal.

To create the AND gate, the researchers placed just GAI at the cell membrane, with just FRB and complexes of FKBP and GID1 free-floating in the cell. This system required all four proteins to link up to produce membrane ruffling, which wouldn't occur without both input chemicals.

Tests showed that each of the engineered cellular logic gates produced the desired response reliably, in a matter of seconds. Additionally, as a second proof of principle, the researchers generated similar logic gates that used fluorescence as an output, which worked just as well and quickly.

Eventually, Inoue notes, researchers might use similar cellular logic gates to build larger, more complex circuits that could form the basis for computers that use cells as basic units. In the meantime, these individual cellular circuits could be engineered to produce specific outputs in the presence of chemicals, making them useful detectors or diagnostic agents. He adds that researchers might also use synthetic logic gate systems like this one to study how cells naturally produce outputs to keep bodily functions running smoothly.


'/>"/>

Contact: Audrey Huang
audrey@jhmi.edu
410-614-5105
Johns Hopkins Medical Institutions
Source:Eurekalert

Related biology news :

1. Researchers develop new self-training gene prediction program for fungi
2. NC State takes lead in crime scene investigation training
3. National and international doctoral training
4. Virtual reality: Keyhole surgeons training could help meet European working time directives
5. Biophysical sciences program receives $2 million training grant
6. Building strong bones: Running may provide more benefits than resistance training, MU study finds
7. Stimulus-funded university research addressing issues from climate change to cancer, creating jobs and training a new generation of scientists
8. Concordia University to build innovative centre for health research and training
9. Kent State receives $2.7 million NSF training grant for environmental aquatic resource sensing
10. Rockefeller Foundation supports expansion, training of e-health work force in developing world
11. Less is more when restraining calories boosts immunity
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/21/2016)... January 21, 2016 ... new market research report "Emotion Detection and Recognition Market by ... Tools (Facial Expression, Voice Recognition and Others), Services, ... forecast to 2020", published by MarketsandMarkets, the global ... reach USD 22.65 Billion by 2020, at a ...
(Date:1/18/2016)... Jan. 18, 2016  Extenua Inc., a pioneering ... the use and access of ubiquitous on-premise and ... with American Cyber.  ... leading transformational C4ISR and Cyber initiatives in support ... latest proven technology solutions," said Steve Visconti ...
(Date:1/11/2016)... Calif. , Jan. 11, 2016 Synaptics ... human interface solutions, today announced that its ClearPad ® ... integration (TDDI) products won two separate categories in the ... Mobile Innovator and Best Technology Breakthrough. The Synaptics ® ... cost, a simplified supply chain, thinner devices, brighter displays ...
Breaking Biology News(10 mins):
(Date:2/11/2016)... , Feb. 11, 2016  Dovetail Genomics™ LLC today ... beta program for a planned metagenomic genome assembly service. ... company,s metagenomic genome assembly method in a talk on ... Biology & Technology conference in Orlando, Fla. ... highly complex datasets is difficult. Using its proprietary ...
(Date:2/11/2016)... ... , ... Global Stem Cells Group, has announced ... new facility will provide advanced protocols and state-of-the-art techniques in cellular medicine, focusing ... The new GSCG clinic is headed by four prominent Ecuadorian physicians, including Pablo ...
(Date:2/10/2016)... , Feb.10, 2016 ASAE is introducing a ... Management Companies (AMC) the option of joining or renewing ... fee determined by staff size, every employee in any ... ASAE and reap all available member benefits.   ... new organizational membership options will allow organizations of any ...
(Date:2/10/2016)... ... 2016 , ... Benchmark Research, a fully-integrated network of ... principal investigators (PI) to the roles of Chief Medical Officer, Clinical Research and ... Chu, a Benchmark Research PI in the Austin office, will assume the role ...
Breaking Biology Technology: