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bioRxiv · 10.1101/2024.12.04.626909

MEMO: A Micro Memo Sensor Detecting microRNA-RISC using an Accurate Cell-Free Expression Platform

Copeland, C. E.·Heitmeier, C. J.·Kim, J.·Kwon, Y.-C.
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Abstract

Circulating microRNAs have emerged as potential prognostic biomarkers of various diseases. They serve as micro memos sent out by cells, which scientists can intercept to gain real-time insights into cellular and disease status. However, establishing a standardized microRNA detection platform remains a challenge. Here, we integrate the RNA-induced silencing complex (RISC), which occupies mature microRNAs, into a complex cell-free synthetic genetic circuit using three different RNA polymerases, creating an innovative microRNA biosensor that is sensitive, precise, and cost-effective. The RISC protects the microRNA degradation during isolation and ensures the elimination of false target interactions, enhancing the detection robustness. With a limit of detection of 81 pM, affordability, and the possibility for on-demand use, this system proves to be a strong miRNA sensing tool.

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Copeland, C. E., Heitmeier, C. J., Kim, J., Kwon, Y.-C.. 2024-12-05. MEMO: A Micro Memo Sensor Detecting microRNA-RISC using an Accurate Cell-Free Expression Platform. https://doi.org/10.1101/2024.12.04.626909

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