TOTEM: A web TOol for Tissue-EnrichMent analysis on gene lists

Analysis of spatiotemporal patterns of gene expression is crucial to decode biological systems responses. High-throughput sequencing allows in-depth transcriptome analyses and experimental designs, providing valuable reference expression atlases. Specifically, testing overrepresentations of tissue-specific genes based on these atlases can provide valuable insights; however, such an approach is not accessible to inexperienced users. Here, we introduce TOTEM (TOol for Tissue-EnrichMent), a web tool designed to calculate enrichment values per tissue by identifying tissue-specific genes from an organ/organism of interest given a user gene list. Results are visually represented, and users gene classified. The utility of TOTEM is manifest when using integrated single cell expression atlases, enabling the study of complicated tissues, with the maximum possible resolution. Its effectiveness is validated by the study of BRL3 role in stress specifically from the vascular tissues. Finally, TOTEMs modular design allows for continual integration of new experiments. TOTEM can be freely accessed at: https://totemwebtool.com.