Establishing an RNA Sensor with High Sensitivity and Dynamic Range Utilizing a Signal Amplifier Platform

Precise control of gene expression in a cell-state-specific
manner
is essential for effective therapeutic interventions in complex and
dynamic disease microenvironments. Traditional targeting strategies
that rely on surface markers or cell type-specific promoters often
assume static cellular identities, limiting effectiveness in context
such as cancer and inflammation, where cell states are highly heterogeneous
and dynamic. RNA sensors, such as RADAR (RNA sensing using Adenosine
Deaminases Acting on RNA), provide a modular, programmable, and nonintegrating
platform for classifying cell states. However, it is also characterized
by low sensitivity and dynamic range, which limits its applications
in detecting low-abundance transcripts. In this work, we integrate
RADAR sensors with a signal amplification circuit to enhance sensitivity
and dynamic range. We demonstrate that this combined RADAR-amplifier
platform enables real-time monitoring of subtle changes in the abundance
of endogenous transcripts under physiological conditions. Our results
demonstrate the utility of this platform for fundamental biological
studies and the development of precision therapeutic strategies.