Within a shared cytoplasm, filamentous actin (F-actin) plays numerous and critical roles across the cell body. Cells rely on actin-binding proteins (ABPs) to organize F-actin and to integrate its polymeric characteristics into diverse cellular processes. Yet, the multitude of ABPs that engage with and shape F-actin make studying a single ABP’s influence on cellular activities a significant challenge. Moreover, without a means of manipulating actin-binding subcellularly, harnessing the F-actin cytoskeleton for synthetic biology purposes remains elusive. Here, we describe a suite of designed proteins, Controllable Actin-binding Switch Tools (CASTs), whose actin-binding behavior can be controlled with external stimuli. CASTs were developed that respond to different external inputs, providing options for turn-on kinetics and enabling orthogonality and multiplexing. Being genetically encoded, we show that CASTs can be inserted into native protein sequences to control F-actin association locally and engineered into structures to control cell and tissue shape and behavior.
This content will become publicly available on January 31, 2025
Bio-synthetic telechelics consisting of polyethylene glycol chains end-capped with the actin-binding peptide, LifeAct, are effective F-actin crosslinkers with contour length dependent control over network mechanics and structure.
more » « less- PAR ID:
- 10507267
- Publisher / Repository:
- The Royal Society of Chemistry
- Date Published:
- Journal Name:
- Soft Matter
- Volume:
- 20
- Issue:
- 5
- ISSN:
- 1744-683X
- Page Range / eLocation ID:
- 971 to 977
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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