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bioRxiv · 10.1101/2024.05.31.596797

Non-disruptive inducible labeling of ER-membrane contact sites using the Lamin B Receptor

Downie, L.·Ferrandiz, N.·Jones, M.·Royle, S. J.
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Abstract

Membrane contact sites (MCSs) are areas of close proximity between organelles that allow the exchange of material, among other roles. The endoplasmic reticulum (ER) has MCSs with a variety of organelles in the cell. MCSs are dynamic, responding to changes in cell state, and are therefore best visualized through inducible labeling methods. However, existing methods typically distort ER-MCSs, by expanding contacts or creating artificial ones. Here we describe a new method for inducible labeling of ER-MCSs using the Lamin B receptor (LBR) and a generic anchor protein on the partner organelle. Termed LaBeRling, this versatile, one-to-many approach allows labeling of different types of ER-MCSs (mitochondria, plasma membrane, lysosomes, early endosomes, lipid droplets and Golgi), on-demand, in interphase or mitotic cells. LaBeRling is non-disruptive and does not change ER-MCSs in terms of the contact number, extent or distance measured; as determined by light microscopy or a deep-learning volume electron microscopy approach. We applied this method to study the changes in ER-MCSs during mitosis and to label novel ER-Golgi contact sites at different mitotic stages in live cells.

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Downie, L., Ferrandiz, N., Jones, M., Royle, S. J.. 2024-05-31. Non-disruptive inducible labeling of ER-membrane contact sites using the Lamin B Receptor. https://doi.org/10.1101/2024.05.31.596797

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