Artificial Gel‐Based Organelles for Spatial Organization of Cell‐Free Gene Expression Reactions

Abstract

In biological cells, chemical processes often occur inside specialized subcellular compartments or organelles. For instance, in eukaryotes mRNA is transcribed and processed inside the nucleus, exported to the endoplasmic reticulum, and translated into the encoded protein. Inspired by this high degree of intracellular organization, we here develop gel‐based artificial organelles that enable sequence‐specific and programmable localization of cell‐free transcription and translation reactions inside an artificial cellular system. To this end, we utilize agarose microgels covalently modified with DNA templates coding for various functions and encapsulate them into emulsion droplets. We show that RNA signals transcribed from transcription organelles can be specifically targeted to capture organelles via hybridization to the corresponding DNA addresses. We also demonstrate that mRNA molecules, produced from transcription organelles and controlled by toehold switch riboregulators, are only translated in translation organelles containing their cognate DNA triggers. Spatial confinement of transcription and translation in separate organelles is thus superficially similar to gene expression in eukaryotic cells. Combining communicating gel spheres with specialized functions opens up new possibilities for programming artificial cellular systems at the organelle level.