title: Endothelial RSPO3 Controls Vascular Stability and Pruning through Non-canonical WNT/Ca(2+)/NFAT Signaling.
abstract: 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.
authors.affiliation: Division of Vascular Oncology and Metastasis, German Cancer Research Center Heidelberg (DKFZ-ZMBH Alliance), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Department of Vascular Biology and Tumor Angiogenesis (CBTM), Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Straße 13-17, 68167 Mannheim, Germany.
authors.forename: Beate
authors.initials: B
authors.lastname: Scholz
authors.affiliation: Division of Vascular Oncology and Metastasis, German Cancer Research Center Heidelberg (DKFZ-ZMBH Alliance), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Korn
authors.affiliation: Division of Vascular Oncology and Metastasis, German Cancer Research Center Heidelberg (DKFZ-ZMBH Alliance), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Department of Vascular Biology and Tumor Angiogenesis (CBTM), Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Straße 13-17, 68167 Mannheim, Germany.
authors.forename: Jessica
authors.initials: J
authors.lastname: Wojtarowicz
authors.affiliation: Division of Vascular Oncology and Metastasis, German Cancer Research Center Heidelberg (DKFZ-ZMBH Alliance), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Institute of Pathology, Heidelberg University, Im Neuenheimer Feld 224, 69120 Heidelberg, Germany.
authors.forename: Carolin
authors.initials: C
authors.lastname: Mogler
authors.affiliation: Division of Signaling and Functional Genomics, German Cancer Research Center Heidelberg, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Department of Cell and Molecular Biology (CBTM), Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Straße 13-17, 68167 Mannheim, Germany.
authors.forename: Iris
authors.initials: I
authors.lastname: Augustin
authors.affiliation: Division of Signaling and Functional Genomics, German Cancer Research Center Heidelberg, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Department of Cell and Molecular Biology (CBTM), Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Straße 13-17, 68167 Mannheim, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Boutros
authors.affiliation: Division of Molecular Embryology, German Cancer Research Center Heidelberg (DKFZ-ZMBH Alliance), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; DNA Demethylation, DNA Repair and Reprogramming, Institute of Molecular Biology, Ackermannweg 4, 55128 Mainz, Germany.
authors.forename: Christof
authors.initials: C
authors.lastname: Niehrs
authors.affiliation: Division of Vascular Oncology and Metastasis, German Cancer Research Center Heidelberg (DKFZ-ZMBH Alliance), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Department of Vascular Biology and Tumor Angiogenesis (CBTM), Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Straße 13-17, 68167 Mannheim, Germany; German Cancer Consortium, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany. Electronic address: augustin@angiogenese.de.
authors.forename: Hellmut G
authors.initials: HG
authors.lastname: Augustin
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D042783:Endothelial Cells / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D008822:Mice, Transgenic; D050778:NFATC Transcription Factors / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics*; D019699:Thrombospondins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D051153:Wnt Proteins / Q000378:metabolism
chemical_list: D050778:NFATC Transcription Factors; C517523:R-spondin3 protein, mouse; D019699:Thrombospondins; D014157:Transcription Factors; D051153:Wnt Proteins; D002118:Calcium
keywords: Moyamoya; NFAT; R-spondin; RNF213; RSPO3; WNT; angiogenesis; non-canonical WNT pathway; vascular pruning; vascular regression; vascular remodeling