Abstract Synthetic cells offer a versatile platform for addressing biomedical and environmental challenges, due to their modular design and capability to mimic cellular processes such as biosensing, intercellular communication, and metabolism. Constructing synthetic cells capable of stimuli‐responsive secretion is vital for applications in targeted drug delivery and biosensor development. Previous attempts at engineering secretion for synthetic cells have been confined to non‐specific cargo release via membrane pores, limiting the spatiotemporal precision and specificity necessary for selective secretion. Here, a protein‐based platform termed TEV Protease‐mediated Releasable Actin‐binding Protein (TRAP) is designed and constructed for selective, rapid, and triggerable secretion in synthetic cells. TRAP is designed to bind tightly to reconstituted actin networks and is proteolytically released from bound actin, followed by secretion via cell‐penetrating peptide membrane translocation. TRAP's efficacy in facilitating light‐activated secretion of both fluorescent and luminescent proteins is demonstrated. By equipping synthetic cells with a controlled secretion mechanism, TRAP paves the way for the development of stimuli‐responsive biomaterials, versatile synthetic cell‐based biosensing systems, and therapeutic applications through the integration of synthetic cells with living cells for targeted delivery of protein therapeutics.
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Massively parallel, computationally guided design of a proenzyme
Significance Proteins have shown promise as therapeutics and diagnostics, but their effectiveness is limited by our inability to spatially target their activity. To overcome this limitation, we developed a computationally guided method to design inactive proenzymes or zymogens, which are activated through cleavage by a protease. Since proteases are differentially expressed in various tissues and disease states, including cancer, these proenzymes could be targeted to the desired microenvironment. We tested our method on the therapeutically relevant protein carboxypeptidase G2 (CPG2). We designed Pro-CPG2s that are inhibited by 80 to 98% and are partially to fully reactivatable following protease treatment. The developed methodology, with further refinements, could pave the way for routinely designing protease-activated protein-based therapeutics and diagnostics that act in a spatially controlled manner.
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- Award ID(s):
- 1541278
- PAR ID:
- 10493070
- Publisher / Repository:
- National Library of Medicine
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 119
- Issue:
- 15
- ISSN:
- 0027-8424
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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