Endothelial RSPO3 Controls Vascular Stability and Pruning through Non-canonical WNT/Ca(2+)/NFAT Signaling

Dev Cell. 2016 Jan 11;36(1):79-93. doi: 10.1016/j.devcel.2015.12.015.


The WNT signaling enhancer R-spondin3 (RSPO3) is prominently expressed in the vasculature. Correspondingly, embryonic lethality of Rspo3-deficient mice is caused by vessel remodeling defects. Yet the mechanisms underlying vascular RSPO3 function remain elusive. Inducible endothelial Rspo3 deletion (Rspo3-iECKO) resulted in perturbed developmental and tumor vascular remodeling. Endothelial cell apoptosis and vascular pruning led to reduced microvessel density in Rspo3-iECKO mice. Rspo3-iECKO mice strikingly phenocopied the non-canonical WNT signaling-induced vascular defects of mice deleted for the WNT secretion factor Evi/Wls. An endothelial screen for RSPO3 and EVI/WLS co-regulated genes identified Rnf213, Usp18, and Trim30α. RNF213 targets filamin A and NFAT1 for proteasomal degradation attenuating non-canonical WNT/Ca(2+) signaling. Likewise, USP18 and TRIM5α inhibited NFAT1 activation. Consequently, NFAT protein levels were decreased in endothelial cells of Rspo3-iECKO mice and pharmacological NFAT inhibition phenocopied Rspo3-iECKO mice. The data identify endothelial RSPO3-driven non-canonical WNT/Ca(2+)/NFAT signaling as a critical maintenance pathway of the remodeling vasculature.

Keywords: Moyamoya; NFAT; R-spondin; RNF213; RSPO3; WNT; angiogenesis; non-canonical WNT pathway; vascular pruning; vascular regression; vascular remodeling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / metabolism
  • Endothelial Cells / metabolism*
  • Gene Expression Regulation, Developmental / genetics*
  • Mice, Transgenic
  • NFATC Transcription Factors / metabolism
  • Signal Transduction / genetics*
  • Thrombospondins / genetics
  • Thrombospondins / metabolism*
  • Transcription Factors / metabolism*
  • Wnt Proteins / metabolism


  • NFATC Transcription Factors
  • R-spondin3 protein, mouse
  • Thrombospondins
  • Transcription Factors
  • Wnt Proteins
  • Calcium