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bioRxiv · 10.1101/2023.08.03.551799

Optogenetic strategies for optimizing the performance of biosensors of membrane phospholipids in live cells

Yao, Y.·Lou, X.·Du, G.·Jin, L.·Li, J.·Liu, J.·Chen, Y.·Cheng, S.·Zhao, T.·Ke, S.·Zhang, L.·Zhang, P.·Xu, Y.·He, L.·Li, H.
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Abstract

High-performance biosensors play a crucial role in elucidating the intricate spatiotemporal regulatory roles and dynamics of membrane lipids. However, enhancing their sensitivity and substrate-detecting capabilities remains a significant challenge. Here, we presented optogenetic-based strategies to optimize phospholipid biosensors. These strategies involved pre-sequestering unbound probes in the cell nucleus to minimize background signals in the cytoplasm. These stored probes could be released from the nucleus in response to blue light according to experimental requirements. Furthermore, we employed optically-controlled phase separation to generate punctate probes that amplified signals and facilitated the visualization of phospholipids in cells. These improved phospholipid biosensors hold great potential for enhancing our understanding of the spatiotemporal dynamics and regulatory roles of membrane lipids in live cells and this methodological insights might be valuable for developing other high-performance biosensors.

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Yao, Y., Lou, X., Du, G., Jin, L., Li, J., Liu, J., Chen, Y., Cheng, S., Zhao, T., Ke, S., Zhang, L., Zhang, P., Xu, Y., He, L., Li, H.. 2023-08-04. Optogenetic strategies for optimizing the performance of biosensors of membrane phospholipids in live cells. https://doi.org/10.1101/2023.08.03.551799

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