Bioengineers add cooperative molecules to their toolkit for programming signal processing

Bioengineers add cooperative molecules to their toolkit for programming signal processing
Synthetic biologists designed a system for engineering cells that respond digitally to analog signals. Cells are pre-programmed to produce transcription factor protein components (top left) in proportion to the strength of an incoming signal. Upon reaching a critical concentration, components self-assemble (top right) into a protein complex that initiates transcription of a pre-programmed target gene. The more modules a self-assembled transcription complex contains (bottom, left to right), the more sharply it responds to the critical threshold. Credit: Rice University



The type of combinatorial signal processing that they've been able to engineer synthetically is what naturally and elegantly do to enable intricate tasks, like those in embryonic development and differentiation.








Using their system, engineered cells are made to produce assembly components in response to a desired chemical or environmental input. In one experiment, they programmed to respond to two different chemicals, and specifically to respond to varying concentrations of the two chemicals in either analog or digital fashion.

In the analog circuits, the response is continuous; if a small concentration of either or both chemicals is present, there is a graded response. But in the digital circuits, there is an all-or-nothing, discrete response—like a signal conversion to binary code, which is only comprised of 0s and 1s, off and on.

By taking advantage of their new ability to adjust the cooperativity between assembly components, they showed that they could convert the cell's response from dull to sharp—the more cooperative the complex, the sharper the response. The sharpness of a response—how acutely and intensely a system responds when a signal reaches a critical threshold—is key for digital signal processing.


That upgrade from analog to digital is the culmination of years of research. The analog-to- and their other synthetic gene circuits can be used to explore and manipulate the regulatory programs that guide immune and stem cell functions with the ultimate goal of developing transformational cell-based therapeutics from engineered human cells.

"It's well known that nature has perfected very powerful information processing with only a small number of parts, but deconvoluting precisely how this works is virtually impossible in human cells due to their complexity," adds Ellis, who was not part of the research. "By recreating the way process information at the DNA level, but in a simple yeast cell model with synthetic parts, they have been able to recreate complex from first principles. This is an excellent example of how thinking like an engineer can unlock a new way to answer major biology questions."

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More information: "Complex signal processing in synthetic gene circuits using cooperative regulatory assemblies" Science (2019). science.sciencemag.org/cgi/doi … 1126/science.aau8287
Journal information: Science

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Citation: Bioengineers add cooperative molecules to their toolkit for programming signal processing (2019, April 18) retrieved 23 July 2019 from https://phys.org/news/2019-04-bioengineers-cooperative-molecules-toolkit.html

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Apr 18, 2019

It is strictly forboten to say that GOD did it. So the irrational attribution to a non-existing sentient "Nature" has to be made. I challenge anyone, no matter their education level to show just how "Nature" has the ability to conceive of a need and to design AND BUILD a solution to fulfill that need. Pointing out existing solutions to existing problems won't do since it's already be done - by the supernatural genius of our God.
