FIGURE 1.

Controlling communication in synthetic cells. Genetically encoded synthetic cell communication systems have been controlled by regulating the expression of αHL using (A) small molecule sensitive riboswitches or (B) transcription factors. (C—left) Transcription factors that recognise acyl-homoserine lactones are typically used to regulate quorum sensing between E. coli and synthetic cells or synthetic cells and other synthetic cells, (C—right) but they have also regulated expression of a large protein pore, PFO, in synthetic cell communication with mammalian cells. (D) Control over communication that does not require genetic control has been demonstrated by using pH-responsive DNA nanostructures and polymers to regulate the fusion of entrapped vesicles with the membrane of a larger vesicle and the release of insulin. (E) In contrast to molecular activation, communication between synthetic cells has been initiated using light-activated DNA. 3OC6-HSL, N-3-oxo-hexanoyl homoserine lactone; αHL, alpha-hemolysin; araC, arabinose-sensitive transcription regulator; BDNF, brain-derived neurotrophic factor; Cat, catalase; Dox, doxycycline; fLuc, firefly luciferase; GFP, green fluorescent protein; Glut 2, glucose transporter 2; GO, glucose oxidase; GOI, gene of interest; HEK293T, human embryonic kidney 293T cells; IPTG, isopropyl ß-d-1-thiogalactopyranoside; LacI, lac repressor; LasI, 3OC12-HSL synthase gene; LasR, 3OC12-HSL transcriptional activator; LuxI, 3OC6-HSL synthase gene; LuxR, 3OC6-HSL transcriptional activator; PEG, polyethylene glycol-5000; PFO, perfringolysin O; RBS, ribosome binding site; TetR, Tet Repressor protein; UV, ultraviolet.