I believe it is now possible to develop a device with controllable moving parts that can build a copy of its structure from significantly simpler components under external computer control.
Lovers of science fiction or disaster scenarios will be disappointed: the device would have only a few dozen parts, would rely heavily on self-assembly, would have no on-board computer, and would require massive quantities of expensive manufactured molecules to be pumped past it just to make it operate at all.
Basically, all it would do is to sort building blocks out of a mixture, stick them together one at a time in linear sequence, and let the resulting chain fold into the desired structure. But it could, in theory, make any desired structure, perhaps with with low enough error rates and high enough speed to assemble hundreds or even thousands of components. And my design only needs dozens.
Based on what I learned at the recent FNANO conference (which had lots and lots of information about DNA structures, and world-class experts on them), I think all the necessary techniques and knowledge are in place. Several of those experts told me that my idea is interesting; no one told me it was impossible.
The practical utility of this design is near zero. But it would blow away an important conceptual barrier, and demonstrate several useful new techniques and approaches (including one that Eric Drexler proposed years ago).
Is anyone planning on giving your idea a go?
Posted by: Summerspeaker | May 08, 2010 at 03:05 PM
Perhaps you should implement it then, or if it does nothing important anyway, release it as open source and let anyone who wishes so do it.
Posted by: Herve | May 10, 2010 at 05:43 AM
I'm already thinking of how to implement it myself. I've gathered several potential collaborators. The main thing I'm looking for now is 1) someone who can help me design the detailed strand sequences; 2) a lab person somewhere near the Bay Area who knows DNA and FRET.
Chris
Posted by: Chris Phoenix, CRN | May 10, 2010 at 12:30 PM
http://nextbigfuture.com/2010/05/billions-of-self-assembled-light.html
I have details on the Duke University self assembled light sensitive and emiting DNA elements.
http://www.cs.duke.edu/~alvy/papers/nsc-ret_final.pdf
Posted by: Brian Wang | May 11, 2010 at 05:08 PM
So Chris are you using FRET to get only information out of your system?
Or is your plan to use FRET to get both information out and conditionally put energy into your system?
Posted by: Jim Heameach | May 12, 2010 at 10:10 AM
Jim, good question. The answer is simple: FRET is for info out.
While writing my answer, I realized that the first experiment can be even simpler than I thought. I had been planning to use DNA strand replacement to get information in - and I still plan to use it for the robot. But I realized that for the first experiment, I can just use temperature change. The experiment gets simpler and simpler...
So you've inspired my next blog post...
Posted by: Chris Phoenix, CRN | May 12, 2010 at 11:17 AM
So if you want these DNA and FRET experts in the SF Bay Area, then post something at Foresight and at the various DIYbio meetups and possibly at appropriate departments at Stanford and at UCB. The (good) hacker philosophy is rampant in these parts. Hell, post your needs in CraigsList.
Posted by: Nitpicker77 | May 16, 2010 at 11:58 AM