MIT–Harvard Researchers Map the Human Striatum Using Slide-Tags Brain Tissue Samples
A team of scientists from the Broad Institute of MIT and Harvard Medical School has produced the most comprehensive molecular map of the human striatum ever reported (https://doi.org/10.64898/2026.03.04.709715). Using fresh-frozen human brain samples provided by the NIH (NeuroBioBank), the researchers identified a previously unrecognized mesoscale architecture within this key brain region. The study offers new insights into how cellular identity, spatial organization, and aging influence human brain function.
The striatum plays a central role in movement, cognition, and emotional processing. However, unlike in model organisms, the human striatum has historically lacked clearly defined anatomical subdivisions. By combining large-scale spatial transcriptomics with single-nucleus sequencing, the team has now revealed a reproducible molecular organization that bridges the gap between cellular diversity and functional circuitry.
Large-Scale Spatial Profiling of the Human Brain
To build this atlas, the researchers analyzed fresh-frozen human brain tissue obtained from the NIH NeuroBioBank. In total, they profiled 1.1 million individual cells from 19 postmortem donors, generating one of the largest spatial transcriptomic datasets ever produced for the human brain.
The study employed Slide-tags, a scalable spatial transcriptomics platform that maps single-nucleus transcriptomes to precise coordinates across centimeter-scale tissue sections. This allowed the team to examine how gene expression patterns change across the entire striatum rather than in isolated microscopic regions.
A key technical step was the efficient isolation of intact nuclei from frozen human brain tissue. The researchers used the Nucleus isolation kit from Invent Biotechnologies (Cat #: BN-020), which enabled the recovery of high-quality nuclei suitable for sensitive single-nucleus RNA sequencing across large tissue areas. Reliable nucleus isolation was critical for generating the high-resolution transcriptomic profiles required to reconstruct the spatial architecture of the striatum.
Six Molecular Zones Define the Human Striatum
Analysis of the spatial dataset revealed a previously unrecognized six-zone organization within the human striatum. These zones were remarkably consistent across all donors and were largely defined along a dorsal–ventral axis. Each zone displayed distinct molecular and functional characteristics. The findings provide the first clear molecular framework for understanding how functional subregions of the human striatum are organized.
Aging Reshapes the Striatal Landscape
To investigate how this architecture changes across the human lifespan, the researchers projected their molecular zoning framework onto a larger cohort of 131 donors. The analysis revealed a striking age-related phenomenon termed “spatial dedifferentiation.”
As individuals age, the distinct transcriptional boundaries between striatal zones begin to blur. Dorsal regions showed the most pronounced changes, suggesting that aging gradually erodes the specialized molecular identity of these territories.
A New Foundation for Human Brain Research
By linking spatial organization with cell-type-specific transcriptional programs, this work establishes a foundational reference for studying human basal ganglia biology. The atlas provides a framework that researchers can use to explore disease mechanisms, circuit specialization, and lifespan changes in the human brain. The study also highlights the growing power of large-scale spatial transcriptomics combined with high-quality nucleus isolation technologies for mapping complex human tissues.
Key Findings of the paper
1. Discovery of Six Zones: The study identified a natural subdivision of the human striatum into six consistent molecular zones (Figure 2B and C). These zones were conserved across all 19 donors and were primarily defined by their dorsal-ventral position. Figure 2B effectively maps the "ring" topology identified in gene expression space onto the consistent, zonated physical distribution of medium spiny neurons (MSNs) across the human striatum.
2. Cellular Specialization: Dorsal zones were found to be enriched for genes associated with synaptic remodeling and plasticity. In contrast, ventral zones showed enrichment for protein chaperones and signaling pathways like Sonic Hedgehog (Figure 6D). This figure highlights the stark transcriptional contrast between dorsal and ventral poles, showing the enrichment of synaptic plasticity genes.
3. Neuron-Astrocyte Signaling: The research highlighted coordinated signaling loops between neurons (MSNs) and astrocytes, such as TGF-beta signaling in dorsal regions and SHH signaling in ventral regions, which maintain these functional territories (Figure 6I). This figure provides evidence for the spatially coordinated signaling loops, illustrating how astrocytes in TGFB-High environments (Zone 1) are enriched for plasticity-promoting factors like GPC6, while neighboring MSNs show increased SHH expression.