Assembling the world's first DNA message
"Everything is theoretically impossible, until it is done." - Robert A. Heinlein
Well... we've done it!!! This week, on August 2nd 2016, our DNA Typewriter typed it's first message!
Our DNA Typewriter has a keyboard made of BabbleBricks, which allow you to construct any message you like. The inner workings of the Typewriter, what really makes it functional, are dependent on a DNA assembly method; the protocol we use to join our Bricks together. Put it this way, a typewriter with keys is useless if the type bars can't print the message on the paper.
Our assembly method is grounded in the features of our BabbleBricks; each Brick exists in both an AB and a BA form. This ensures that during assembly, only Bricks, or in our case - words, can stick to each other in the correct order. This prevents repeats of a BabbleBrick joining on to the larger construct.
Assembly starts by ligating our first BabbleBrick to an Anchor sequence, this sequence does exactly what you would expect; anchors the BabbleBrick construct during assembly. Each growing construct, or BabbleBlock, is anchored to a magnetic bead. By performing our assembly reactions with magnetic beads on a magnetic rack, we are able to anchor and hold our growing BabbleBlock in place. Without this, our DNA would simply wash away throughout the process.
A picture of an assembly in process - the magnetic rack is pictured in the back. If you look closely, you can see the cluster of magnetic beads inside the Eppendorf tube.
After ligating the Anchor sequence to the beads, we grow our BabbleBlock by cycles of BabbleBrick addition, ligation and washing steps. The washing steps are important because they remove any excess or unligated BabbleBrick from the solution. Each addition step takes only 10 minutes - standard DNA ligation procedures can take up to 2 hours! In this way our assembly method is rapid and efficient.
Our assembly method has been a work-in-progress for many weeks now; we've performed countless assays and trials and had to overcome a range of different obstacles. We've had to figure out appropriate anchor and bead quantities, the amount of time each step takes and the most efficient buffers to use during our wash steps.
After many failed attempts, this week we have successfully constructed a two word and a six word sentence. We're still trying to figure out the longest BabbleBlock we can construct, so we're back in the lab today to assemble more Bricks! Once we've done this we'll upload our assembly protocol and all of our results, so stay tuned!
All of our hard work has paid off and we can proudly say that we have a functional proof of concept for our project.
@EdiGEM2016
