Search PubMedSearch

Biomedical subjects

Ao Chen

Publications and source records attributed to Ao Chen.

3 recordsLinked to original sources

Full-length single-cell spatial transcriptomics reveals spatial and cell-type-specific transcript isoforms in the primate brain.

The primate brain exhibits complex RNA alternative splicing heterogeneity crucial for functional complexity, yet systematic spatial isoform characterization has been lacking. We developed Fullscope-seq, a full-length single-molecule large field-of-view spatial transcriptomics sequencing method at single-cell resolution, based on programmed concatenation cDNA for multiple long-read sequencing platforms. Applying Fullscope-seq to the macaque brain, we uncovered thousands of genes exhibiting differential transcript usage (DTU) across cortical layers, cell types and brain regions. Fullscope-seq resolved hundreds of major isoform switches across distinct brain regions and identified DTUs between superficial and deep cortical layers. Cortical layer-specific DTUs showed cell-composition dependence, whereas regional DTUs were regulated according to both cellular composition and spatial contexts. These isoform variations showed substantial enrichment for neuropsychiatric disorder-associated genes and were conserved across platforms and species. Our study establishes a scalable framework for spatial isoform analysis and provides a resource for understanding transcriptomic diversity in complex tissues.

Animals

Unconventional codon usage bias mediates mRNA translational dynamics in macrophages.

Macrophages require rapid and tightly controlled regulatory mechanisms to respond to environmental disruptions. While transcriptional regulation has been well characterized, the mechanisms underlying translational control in macrophages remain poorly understood. Here, we investigated the dynamics of mRNA translation in mouse macrophages during acute, intermediate, and prolonged LPS exposure. Our results reveal clear phase-specific translational regulation during macrophage polarization, which initially increases the synthesis of inflammatory mediators and cytokines, while simultaneously suppressing the expression of cell cycle-related genes. Mechanistically, we observed pervasive upstream translation in the 5' UTRs of cell cycle-related mRNAs, which contributes to cell cycle arrest during the early phase of inflammatory response. Notably, we identified a unique codon preference toward A/U in the third position of codons in macrophages, which contrasts with the G/C preference commonly observed in other tissues. AU codon preference increases the stability and translation efficiency of cell cycle-related mRNAs, promoting cell cycle restoration after extended LPS exposure. These findings reveal that uORF translation and codon usage bias are critical components of translational regulation during macrophage polarization, highlighting a potential therapeutic intervention for modulating immune activation via macrophage-specific codon optimization.

Animals

Stereo-cell: Spatial enhanced-resolution single-cell sequencing with high-density DNA nanoball-patterned arrays.

Single-cell sequencing technologies have advanced our understanding of cellular heterogeneity and biological complexity. However, existing methods face limitations in throughput, capture uniformity, cell size flexibility, and technical extensibility. We present Stereo-cell, a spatial enhanced-resolution single-cell sequencing platform based on high-density DNA nanoball (DNB)-patterned arrays, which enables scalable and unbiased cell capture at a wide input range and supports high-fidelity transcriptome profiling. Stereo-cell further allows integration with imaging-based modalities and multiomics strategies, including immunofluorescence and epitope profiling. This platform is also compatible with profiling extracellular vesicles, microstructures, and large cells, whereas its spatial resolution facilitates in situ analysis of cell-cell interactions, cellular microenvironments, and subcellular transcript localization. Together, Stereo-cell provides a flexible framework for expanding single-cell research applications.

Animals