# An artificial cell capable of signal transduction mediated by ADRB2 for the regulation of glycogenolysis

## TL;DR

Researchers created an artificial cell that can respond to external signals to control glycogen breakdown, mimicking natural cell signaling.

## Contribution

The novel contribution is the successful reconstitution of a GPCR signaling pathway in artificial cells to regulate glycogenolysis.

## Key findings

- cAMP production in artificial cells is dose-dependent on isoproterenol with a maximum amplification of 22.45 ± 2.14.
- ISO stimulation triggers glycogen conversion to glucose-1-phosphate and NADPH via phosphorylase kinase and glycogen phosphorylase activation.
- The GPCR-mediated pathway in artificial cells enables progressive signal amplification and downstream metabolic regulation.

## Abstract

Bottom-up construction of artificial cells helps elucidate the working mechanism of cells. Signal transduction from extracellular to intracellular artificial cells is essential for autonomous artificial cells. It remains highly challenging to reconstitute G protein-coupled receptor (GPCR) signaling pathways to regulate downstream metabolism in artificial cells. Here, we reconstitute β2-adrenergic receptor, Gs subunit α and adenylate cyclase V into artificial cell membranes to enable signal transduction from extracellular isoproterenol (ISO) to intracellular cAMP (visualization via Epac1-cAMP probes). cAMP production is ISO dose-dependent, with a maximum amplification fold of 22.45 ± 2.14. By encapsulating the glycogenolytic pathway, cAMP activates protein kinase A, triggering phosphorylation of phosphorylase kinase and glycogen phosphorylase to convert glycogen to glucose-1-phosphate (G-1-P). G-1-P is further converted to 6-phosphogluconolactone accompanying with NADPH. ISO stimulation induces G-1-P and NADPH generation, achieving progressive signal amplification. The successful reconstitution of GPCR-mediated signaling pathway in artificial cells paves the way for developing autonomous artificial cells.

Signal transduction from extracellular to intracellular artificial cells is essential for autonomous artificial cells. Here the authors reconstitute a G protein-coupled receptor (GPCR) signaling pathway in an artificial cell to regulate downstream glycogen metabolism.