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bioRxiv · 10.1101/2020.08.19.248898

Comparing Lifeact and Phalloidin for Super-resolution Imaging of Actin in Fixed Cells

Mazloom-Farsibaf, H.·Farzam, F.·Fazel, M.·Wester, M. J.·Meddens, M. B. M.·Lidke, K. A.
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Abstract

Visualizing actin filaments in fixed cells is of great interest for a variety of topics in cell biology such as cell division, cell movement, and cell signaling. We investigated the possibility of replacing phalloidin, the standard reagent for super-resolution imaging of F-actin in fixed cells, with the actin binding peptide lifeact. We compared the labels for use in single molecule based super-resolution microscopy, where AlexaFluor 647 labeled phalloidin was used in a (d)STORM modality and Atto 655 labeled lifeact was used in a single molecule imaging, reversible binding modality. We found that imaging with lifeact had a comparable resolution in reconstructed images and provided several advantages over phalloidin including lower costs, the ability to image multiple regions of interest on a coverslip without degradation, simplified sequential super-resolution imaging, and more continuous labeling of thin filaments.

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Mazloom-Farsibaf, H., Farzam, F., Fazel, M., Wester, M. J., Meddens, M. B. M., Lidke, K. A.. 2020-08-20. Comparing Lifeact and Phalloidin for Super-resolution Imaging of Actin in Fixed Cells. https://doi.org/10.1101/2020.08.19.248898

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