CaMP-screen, a screening system for calcium signaling
Inside cells, tiny pulses of calcium direct vital processes such as muscle movement, brain activity and immune responses. Any disruption of this delicate signaling system can lead to diseases ranging from immune disorders to neurodevelopmental conditions. Yet many of the genes involved in controlling these signals have remained a mystery until now.
A screening system to discover genes involved in calcium signaling
Researchers from the laboratory of Pr Nicolas Demaurex have developed a powerful new method, called CaMP-Screen, to rapidly identify genes that regulate calcium signals across large populations of cells. This method, described in their , combines a calcium-sensitive fluorescent protein (CaMPARI2), flow cytometry, and genomic interrogation to measure subtle shifts in calcium activity, something that was previously only possible using time-consuming, single-cell techniques.
The CaMP-Screen method allows to detect calcium signals through changes in fluorescence, from green to red, across large populations of cells. © Supplementary material from Kouba et al. 2025
With CaMP-Screen, the team discovered dozens of genes that either amplify or suppress calcium signaling. Among them, one gene attracted in particular their attention, the TIM1 gene. They discovered that switching off the TIM1 gene, which encodes a protein found on the surface of immune T cells, led to stronger calcium signals when the cells were at rest. This suggests that TIM1 normally acts as a brake, keeping T cells from activating too easily.
Potential implications
By uncovering hidden regulators of calcium signaling, CaMP-Screen opens new paths for understanding how cells maintain internal balance, and what happens when that balance is lost. The method could accelerate the discovery of therapeutic targets for immune diseases, neurological disorders, and rare genetic conditions.