Abstract / Summary
Abstract Background: Cerebrovascular development requires a precisely orchestrated transition from active angiogenesis to blood-brain barrier (BBB) maturation, yet the epigenomic dynamics governing this transition remain largely unexplored. Cerebrovascular endothelial cell-specific tools for multi-omic profiling are lacking.
Methods: We generated a cerebrovascular-specific transgenic zebrafish line Tg( slc2a1a :EGFP) and performed integrated RNA-seq and ATAC-seq on FACS-purified cerebrovascular endothelial cells at 28 hpf, 3 dpf, and 7 dpf.
Results: Temporal transcriptomic profiling revealed a progressive shutdown of angiogenesis-related genes ( nrp1b , cxcr4b , apln ) tightly coupled with declining chromatin accessibility at their candidate distal regulatory elements, together with the gradual closure of caveolae-mediated transcytosis and the assembly of tight junctions. Transcription factor motif analysis revealed a developmental switch from early ETS/KLF/TEAD enrichment to late Forkhead (FoxC/FoxO) enrichment. As a correlated epigenomic feature, all six detected DNA methyltransferase (DNMT) family members showed coordinated downregulation at both RNA and chromatin accessibility levels; broad-spectrum methylation inhibition (RG108) impaired hindbrain vascular sprouting and central artery development, whereas DNMT1-selective inhibition (GSK3685032) produced little or no detectable phenotype.
Conclusions: This study provides a temporal multi-omic atlas of zebrafish cerebrovascular endothelial barrier maturation and a transgenic tool for cerebrovascular-specific profiling, showing that chromatin accessibility remodeling coordinates the angiogenic-to-barrier transition. DNMT family downregulation is reported as a correlated epigenomic feature rather than direct evidence of mechanism.