Astrocyte glucocorticoid receptor signalling restricts neuronal plasticity

Key Points:

• The study used various genetically modified mouse lines maintained under controlled light/dark cycles, with some subjected to chronic darkness (DR) to study visual experience effects on brain development, particularly in the primary visual cortex (V1).
• Multiple advanced molecular and imaging techniques were applied, including SHARE-seq for combined chromatin accessibility and RNA profiling, MERFISH for spatial transcriptomics, CUT&RUN for profiling protein-DNA interactions, ATAC-seq for chromatin accessibility, bulk and single-nucleus RNA-seq for gene expression, and electrophysiology for functional neuronal assessments.
• Viral vectors were stereotactically injected into neonatal or adult mouse V1 to manipulate gene expression specifically in astrocytes or neurons, enabling cell type-specific analyses of glucocorticoid receptor (GR) functions and their role in experience-dependent plasticity.
• Bioinformatics pipelines involved robust quality control, clustering, differential expression and accessibility analyses, transcription factor motif enrichment, and integration of multi-omics datasets to identify experience- and GR-regulated gene programs and regulatory elements in astrocytes and neurons during development.
• Functional assays included in vivo ocular dominance plasticity measurements following monocular deprivation, ex vivo electrophysiology to assess synaptic currents and inhibitory inputs, and immunofluorescent staining to quantify protein expression and synaptic markers, all performed with rigorous controls and blinded analysis to elucidate the role of astrocyte GR signaling in cortical circuit maturation.