Mach, S. | bioRxiv Science

bioRxiv2026

A glial source of noradrenaline shapes synaptic integration and motor adaptation

Noradrenaline is a major neuromodulator that shapes neural circuit dynamics and behavior. Prevailing models attribute noradrenergic supply exclusively to long-range inputs from distant nuclei. Yet noradrenergic input can be weak in regions that nonetheless show marked noradrenergic modulation, suggesting additional sources. This mismatch is salient in the cerebellum, where noradrenaline influences behavior despite sparse innervation. Here, we identify Bergmann glia, radial cerebellar astrocytes, as a source of noradrenaline. Using two-photon imaging and cell-type-specific genetic manipulations, we show that Bergmann glia can synthesize and release noradrenaline through a calcium-dependent mechanism requiring the vesicular monoamine transporter VMAT2. Glia-derived noradrenaline modulates synaptic integration in Purkinje neurons and is required for motor adaptation. Together, these findings identify a glial pathway that complements the canonical long-range view of noradrenaline supply.

neuroscience↗

bioRxiv2026

Sharp and Fast Dynamic Extraction and Tracking of Emitted Cellular Transients

Genetically encoded fluorescent sensors have expanded our ability to image cellular activity and transmitter release. Yet, sparse and low-salience events remain difficult to resolve against complex and fluctuating fluorescence backgrounds. Here we introduce DETECT, Dynamic Extraction and Tracking of Emitted Cellular Transients, which combines adaptive background suppression, probabilistic classification and multi-object tracking to extract fluorescence events while preserving their identity. Across synthetic datasets, DETECT improved detection and segmentation accuracy and reduced computational cost relative to established event-based methods. We validated DETECT across confocal, two-photon and miniscope imaging, ex vivo and in vivo, using calcium indicators and monoamine sensors. Beyond its technical performance, DETECT extends event-based analysis to low-salience fluorescence signals while resolving events spanning broad ranges of amplitude, morphology and dynamics. By resolving spontaneous dopamine and noradrenaline signals as distinct, trackable release events, DETECT reveals the spatiotemporal organization of neuromodulatory activity and provides a broadly applicable approach to quantitative fluorescence analysis.

neuroscience↗