GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE345nnn/GSE345248/primaryOK200TranscriptomicsMus musculusExpression profiling by high throughput sequencinghttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE345248GEOGSEfalseThe External Globus Pallidus is a Major Basal Ganglia Output Hub with Action-Specific Circuits [Gpe 10X]The indirect basal ganglia pathway is classically viewed as suppressing movement via the external globus pallidus (GPe), which has largely been regarded as an inhibitory relay nucleus. Using whole-brain projection mapping, single-neuron reconstruction, transcriptomics, rabies tracing, and closed-loop optogenetics, we show that the GPe is itself a major modular output structure, organized into parallel channels that selectively control distinct actions. Projection-defined GPe populations directly target thalamic and brainstem motor centers and exhibit action-specific dynamics and functions. GPe→PPN neurons are selectively suppressed during locomotion, and their manipulation bidirectionally controls locomotion. Critically, D2-SPN activation promotes locomotion through disinhibition of this pathway, revealing a direct movement-facilitating route stemming from D2-SPNs. In contrast, GPe→Pf neurons selectively regulate forelimb action sequences. These findings establish the GPe as a modular basal ganglia output structure and substantially revise canonical models of direct/indirect pathway function.2026/08/31GSE345248GSM10000152GSM10000150GSM1000015124247345248Mus musculus