PT  - JOURNAL ARTICLE
AU  - Patrick M. Caveney
AU  - Rosemary M. Dabbs
AU  - William T. McClintic
AU  - S. Elizabeth Norred
AU  - C. Patrick Collier
AU  - Michael L. Simpson
TI  - Controlling Cell-Free Gene Expression Behavior by Tuning Membrane Transport Properties
AID  - 10.1101/604454
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 604454
4099  - http://biorxiv.org/content/early/2019/04/10/604454.short
4100  - http://biorxiv.org/content/early/2019/04/10/604454.full
AB  - Controlled transport of molecules across boundaries for energy exchange, sensing, and communication is an essential step toward cell-like synthetic systems. This communication between the gene expression compartment and the external environment requires reaction chambers that are permeable to molecular species that influence expression. In lipid vesicle reaction chambers, species that support expression – from small ions to amino acids – may diffuse across membranes and amplify protein production. However, vesicle-to-vesicle variation in membrane permeability may lead to low total expression and high variability in this expression. We demonstrate a simple optical treatment method that greatly reduces the variability in membrane permeability. When transport across the membrane was essential for expression, this optical treatment increased mean expression level by ~6-fold and reduced expression variability by nearly two orders of magnitude. These results demonstrate membrane engineering may enable essential steps toward cell-like synthetic systems. The experimental platform described here provides a means of understanding controlled transport motifs in individual cells and groups of cells working cooperatively through cell-to-cell molecular signaling.