Long Cai - Spatial Genomics

Professor Cai presented his recent findings in spatial transcriptomics technology. Firstly, He introduced the Sequential Fluorescence in situ Hybridization (SeqFISH+) technique, which permitted the identification of more than 10,000 genes through multiple cycles of hybridization using various fluorescent probes, and visualization through confocal microscopy. This technique also enabled the localization of introns. Through spatial transcriptomics analysis, his team discovered a group of "neighboring" cells in an acute kidney injury model that interacted with renal epithelium. They noticed varying gene expression patterns in fibroblast cells depending on their spatial distribution. This approach overcame the drawbacks of traditional single-cell sequencing, where crucial spatial information was lost during cell dissociation.
The Cai lab also noted that single-cell spatial genomics provided crucial insights across DNA, protein, and chromatin epigenetic levels. At the epigenetic level, in situ imaging revealed the distribution of DNA, chromatin, and various modifications within the cell nucleus. Differences in heterochromatin distribution across different cell types were observed, along with the discovery of repositioning of DNA to distinct heterochromatin regions across cell types. In summary, spatial genomics offered a potent tool for studying gene expression, cellular interactions, and epigenetic regulation within their natural spatial context, providing valuable insights into complex biological processes.