Topologically associating domains are disrupted by evolutionary genome rearrangements forming species-specific enhancer connections in mice and humans

Cell Rep. 2022 May 3;39(5):110769. doi: 10.1016/j.celrep.2022.110769.

Abstract

Distinguishing between conserved and divergent regulatory mechanisms is essential for translating preclinical research from mice to humans, yet there is a lack of information about how evolutionary genome rearrangements affect the regulation of the immune response, a rapidly evolving system. The current model is topologically associating domains (TADs) are conserved between species, buffering evolutionary rearrangements and conserving long-range interactions within a TAD. However, we find that TADs frequently span evolutionary translocation and inversion breakpoints near genes with species-specific expression in immune cells, creating unique enhancer-promoter interactions exclusive to the mouse or human genomes. This includes TADs encompassing immune-related transcription factors, cytokines, and receptors. For example, we uncover an evolutionary rearrangement that created a shared LPS-inducible regulatory module between OASL and P2RX7 in human macrophages that is absent in mice. Therefore, evolutionary genome rearrangements disrupt TAD boundaries, enabling sequence-conserved enhancer elements from divergent genomic locations between species to create unique regulatory modules.

Keywords: B cells; CCR5; CD163; CP: Immunology; CXCL13; CXCR4; EOMES; IDO1; IL23R; IL6; IRF4; JUN; NAMPT; NOS2; P2RX7; T cells; TLR9; genome topology; genomic structural variation; iNOS; macrophages.

MeSH terms

  • Animals
  • Chromatin*
  • Enhancer Elements, Genetic / genetics
  • Evolution, Molecular
  • Gene Rearrangement / genetics
  • Genome, Human*
  • Genomics
  • Humans
  • Mice

Substances

  • Chromatin