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bioRxiv · 10.1101/2025.07.03.662901

Organism-wide spatiotemporal profiling of gene expression utilizing a X-CreERT2/Ai9 tracing system

Li, F.·Yao, Q.·Chen, M.·He, S.·Ran, Y.·Li, J.·Lin, L.·Xiao, G.
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Abstract

This study utilizes a novel inducible X-CreERT2/Ai9 system to comprehensively delineate the spatial expression landscape of Fermt2, which encodes a key focal adhesion protein Kindlin-2, across organs in mice. We can confirm all known Kindlin-2-expressing cells and identify any previously unknown Kindlin-2-expressing cells and those that do not express Kindlin-2 in all tissues/organs in mice. We have developed this cost-effective, rapid, and high-fidelity system and implemented its first whole-organism application for comprehensive gene expression profiling. This work not only provides unprecedented insights into roles of Kindlin-2 in diverse physiologies and pathologies, but also establishes the inducible X-CreERT2/Ai9 system as a powerful paradigm-shifting platform for organism-wide pan-organ spatiotemporal expression profiling of any target genes encoding any proteins and micro-RNAs. By enabling high-resolution mapping of drug target expression, this system may lay critical groundwork for elucidating previously unknown adverse and beneficial effects of targeted therapies, offering transformative potential for precision medicine.

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Li, F., Yao, Q., Chen, M., He, S., Ran, Y., Li, J., Lin, L., Xiao, G.. 2025-07-03. Organism-wide spatiotemporal profiling of gene expression utilizing a X-CreERT2/Ai9 tracing system. https://doi.org/10.1101/2025.07.03.662901

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