Engineered Molecular Probes for Systematic Studies of Cellular Response in Collective Cell Migration

Abstract

The investigation of complex biological processes, such as wound healing, cell migration, cancer cell invasion, and gene regulatory networks can be benefited tremendously by novel biosensing techniques with high stability and spatiotemporal resolution. In particular, molecular probes with qualities including high stability, sensitivity, and specificity are highly sought-after for long-term monitoring of gene expression in individual cells. Among different single-cell analysis techniques oligonucleotide optical probes is a promising detection method to monitor the dynamics of cellular responses. Herein, the design and optimization of double-stranded LNA probes are first investigated. With alternating DNA/LNA monomers for optimizing the stability and specificity, we show that the probe is highly stable in living cells and is capable of detecting changes in gene expression induced by external stimuli. Using dsLNA probes we then demonstrate the novel approaches to monitor the spatiotemporal gene expression response during cell injury. Our results also suggest a potential autoregulatory role of Nrf2 in injury induced EMT. We also show that the signaling level of dsLNA probe can serve as a molecular signature for the leader cells near the wound which allows us to track the behaviors of leader cells during collective cell migration. Finally multimodal GNR-LNA approach is proposed to map spatiotemporal gene expression profile and reveal dynamic characteristics of heat shock response in photothermal operations.