Difference between revisions of "Featured Parts:Cell-Cell-Signaling"

Revision as of 15:10, 6 May 2006

Introduction

Coordinating the behavior of cells within a population requires cell-cell signaling. Information transfer between different groups of cells can also be enabled by cell-cell signaling. The registry contains parts and devices to enable this inter-cell communication.

Cell-cell signaling technology

Most of the existing methods to enable cell-cell signaling borrow technology from bacterial quorum sensing systems Bassler. The best characterized of these is the LuxI/R system from V. fischeri Nealson and its homologs. LuxI is a synthase that converts SAM into a small molecule called an acyl-homoserine lactone (AHL). That molecule can diffuse across cell membranes and is stable in growth media at a range of pH. LuxR is a constitutively expressed protein that can bind AHL. When bound to AHL it can stimulate transcription from the right hand lux promoter. In the natural system, this promoter controls transcription of the LuxI enzyme leading to a positive feedback loop that increases transcription from the right hand lux promoter. As well as controlling the transcription of luxI, the promoter also controls transcription of luciferase.

A range of similar systems exist in other bacteria using homologous proteins that synthesize and respond to slightly modified versions of the V. fischeri AHL molecules. Differing levels of cross-talk exist among these different systems

Device classes

A minimal set of devices to enable cell-cell signaling is a sender device and a receiver signal. These devices are sufficient to enable basic communication between cells in a population of bacteria. These devices have been defined and some proofs of concept tested. We expect that further classes of devices will be described in the future.

Sender devices

Currently, we define a sender device as a device that accepts an input of PoPS and outputs a rate of signaling molecule synthesis.

Receiver devices

We define a receiver device as a device that accepts an input of a signaling molecule and produces a PoPS output.

The parts

References

<biblio>
Bassler pmid=16212498 Nealson pmid=396467

</biblio>