Spatiotemporal Regulation of Cell Fate in Living Systems Using Photoactivatable Artificial DNA Membraneless Organelles

Coacervates formed by liquid–liquid phase separation emerge as important biomimetic models for studying the dynamic behaviors of membraneless organelles and synchronously motivating the creation of smart architectures with the regulation of cell fate. Despite continuous progress, it remains challenging to balance the trade-offs among structural stability, versatility, and molecular communication for regulation of cell fate and systemic investigation in a complex physiological system. Herein, we present a self-stabilizing and fastener-bound gain-of-function methodology to create a new type of synthetic DNA membraneless organelle (MO) with high stability and controlled bioactivity on the basis of DNA coacervates. Specifically, long single-strand DNA generated by rolling circle amplification (RCA) is selected as the scaffold that assembles into membraneless coacervates via phase separation. Intriguingly, the as-formed DNA MO can recruit RCA byproducts and other components to achieve self-stabilization, nanoscale condensation, and function encoding. As a proof of concept, photoactivatable DNA MO is constructed and successfully employed for time-dependent accumulation and spatiotemporal management of cancer in a mouse model. This study offers new, important insights into synthetic membraneless organelles for the basic understanding and manipulation of important life processes.

Coacervate membraneless organelles formed through liquid−liquid phase separation (LLPS) have been actively investigated as an emerging cargo delivery platform to harbor proteins, RNAs, and therapeutic molecules. However, a trade-off among structural stability, versatility, and molecular communication in physiological conditions hampers their application for systemic administration. Our study develops self-stabilizing and fastener-bound gain-of-function DNA membraneless organelles (MOs). Unlike traditional approaches to obtain functional MOs via complicated surface coating or hybridization, long single-strand DNA coacervates are used as scaffolds, enabling self-stabilization and function encoding by simply recruiting surrounding components during LLPS for systematic regulation of cell fate, without loss of communication properties.