18 November 2013
ByAppeared in BioNews 731
A system that allows researchers to control a tiny cellular transport network has been developed by researchers at the Universities of Oxford and Warwick.
In the system DNA acts like a foreman on
the nanoscale construction site, assembling and directing the operation of shuttles that transport molecular cargo along cellular components called microtubules.
'DNA is an excellent building block for constructing synthetic molecular systems, as we can program it to do whatever we need,' said Adam Wollman, who conducted the research at the University of Oxford's Department of Physics.
This set-up served as the inspiration for the system. 'One of the more sci-fi visions of nanotechnology is the creation of moving "nanobots", but it turns out that nature got there first', said Wollman, speaking to the online magazine Motherboard.
The Oxford team fused the kinesin with a short, synthetic DNA strand loaded with information for either assembly of the network or transportation. 'Assembler' nanobots were made with two kinesin proteins, allowing them to move tracks around to assemble the network, whereas the 'shuttles' only need one kinesin protein to travel along the tracks.
The group used fluorescent green dyes as cargo to demonstrate the system, a method inspired by melanophore, a pigment used by fish cells to control their colour.
'We first use assemblers to arrange the track into spokes, triggered by the introduction of ATP (adenosine triphosphate), then send in shuttles with fluorescent green cargo which spread out across the track', explains Wollman. 'When we add more ATP, the shuttles all cluster in the centre of the track where the spokes meet'.
The system also allows the researchers to reverse the process, or 'demolish' the site, by programming the shuttles to signal the cargo-carrying shuttles to release the fluorescent cargo into the environment and dismantle the tracks.
The developers of the self-construction system say it has the potential to speed up chemical reactions used in biotechnology by bringing the necessary compounds together into a central hub.