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bioRxiv · 10.1101/2022.01.28.478241

CRY-BARs: Versatile light-gated molecular tools for the remodeling of membrane architectures

Wurz, A. I.·Bunner, W. P.·Szatmari, E. M.·Hughes, R. M.
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Abstract

BAR (Bin, Amphiphysin and Rvs) protein domains are responsible for the generation of membrane curvature and represent a critical mechanical component of cellular functions. Thus, BAR domains have great potential as components of membrane-remodeling tools for cell biologists. In this work, we describe the design and implementation of a family of versatile light-gated I-BAR domain containing tools ( CRY-BARs) with applications in the remodeling of membrane architectures and the control of cellular dynamics. By taking advantage of the intrinsic membrane binding propensity of the I-BAR domain, CRY-BARs can be used for spatial and temporal control of cellular processes that require induction of membrane protrusions. Using cell lines and primary neuron cultures, we demonstrate that the CRY-BAR optogenetic tool reports membrane dynamic changes associated with cellular activity. Moreover, we provide evidence that Ezrin acts as a relay between the plasma membrane and the actin cytoskeleton and therefore is an important mediator of switch function. Overall, CRY-BARs hold promise as a useful addition to the optogenetic toolkit to study membrane remodeling in live cells.

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Wurz, A. I., Bunner, W. P., Szatmari, E. M., Hughes, R. M.. 2022-01-28. CRY-BARs: Versatile light-gated molecular tools for the remodeling of membrane architectures. https://doi.org/10.1101/2022.01.28.478241

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