Turn-On Protein Switches for Controlling Actin Binding in Cells

Effiong, U. M.; Khairandish, H.; Ramirez-Velez, I.; Wang, Y.; Belardi, B.

doi:10.1101/2023.10.26.561921

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bioRxiv · 10.1101/2023.10.26.561921

Turn-On Protein Switches for Controlling Actin Binding in Cells

Effiong, U. M.·Khairandish, H.·Ramirez-Velez, I.·Wang, Y.·Belardi, B.

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Abstract

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 ABPs 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. Being genetically encoded, we show that CASTs can be inserted into native protein sequences to control F-actin association locally and engineered into new structures to control cell and tissue shape and behavior.

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Effiong, U. M., Khairandish, H., Ramirez-Velez, I., Wang, Y., Belardi, B.. 2023-10-26. Turn-On Protein Switches for Controlling Actin Binding in Cells. https://doi.org/10.1101/2023.10.26.561921

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