Radio waves switch proteins on and off.
6 December 2002
PHILIP BALL

Remote-controlled bacteria could be just around the corner. Researchers have found a way to switch cell processes on and off with radio waves.

The goal is "microbial machines", Joseph Jacobson of the Massachusetts Institute of Technology in Cambridge told this week's Materials Research Society meeting in Boston.

Cells, he explained, could be equipped with a toolbox of 'software' - such as the ability to glow periodically1. Remote-controlled enzymes could cut and paste these modules as if downloading a particular program into the cells. This is a long way off, but the components are taking shape.

Jacobson's team uses an electromagnetic field to switch on and off an enzyme that snips open the genetic messenger molecule RNA. First they attach a tiny particle of gold to the enzyme.

Only millionths of a millimetre across, the gold nanoparticle acts as an antenna, harvesting energy from a radio-frequency electromagnetic field. This energy breaks up the enzyme, rendering it useless. When the field is switched off, the parts of the enzyme re-assemble of their own accord.

Earlier this year the same team manipulated DNA in a similar way2 . They stuck a gold antenna to DNA strands that spontaneously curl up into hairpin structures where the two ends zip together. A radio-frequency pulse picked up by the gold antenna opened up the hairpin.

Showing that the approach works for proteins too greatly increases the range of things that might be done with it - proteins orchestrate nearly all the chemical processes in a cell.

References
Elowitz, M. B. & Leibler, S. A synthetic oscillatory network of transcriptional regulators. Nature, 403, 335 - 338, (2000). |Article|
Hamad-Schifferli, K., Schwartz, J. J., Santos, A.T., Zhang, S. & Jacobson, J. M. Remote electronic control of DNA hybridization through inductive coupling to an attached metal nanocrystal antenna. Nature, 415, 152 - 155, (2002).

Source: www.nature.com