2. Academic Validation
  3. The Orphan Receptor Tie1 Controls Angiogenesis and Vascular Remodeling by Differentially Regulating Tie2 in Tip and Stalk Cells

The Orphan Receptor Tie1 Controls Angiogenesis and Vascular Remodeling by Differentially Regulating Tie2 in Tip and Stalk Cells

  • Cell Rep. 2015 Sep 22;12(11):1761-73. doi: 10.1016/j.celrep.2015.08.024.
Soniya Savant 1,  Silvia La Porta 2,  Annika Budnik 2,  Katrin Busch 3,  Junhao Hu 2,  Nathalie Tisch 4,  Claudia Korn 2,  Aida Freire Valls 2,  Andrew V Benest 2,  Dorothee Terhardt 2,  Xianghu Qu 5,  Ralf H Adams 6,  H Scott Baldwin 5,  Carmen Ruiz de Almodóvar 4,  Hans-Reimer Rodewald 3,  Hellmut G Augustin 7
Affiliations

Affiliations

  • 1 Division of Vascular Oncology and Metastasis, German Cancer Research Center (DKFZ-ZMBH Alliance), 69120 Heidelberg, Germany; Department of Vascular Biology and Tumor Angiogenesis (CBTM), Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany.
  • 2 Division of Vascular Oncology and Metastasis, German Cancer Research Center (DKFZ-ZMBH Alliance), 69120 Heidelberg, Germany.
  • 3 Division of Cellular Immunology, German Cancer Research Center, 69120 Heidelberg, Germany.
  • 4 Biochemistry Center BZH, Heidelberg University, 69120 Heidelberg, Germany.
  • 5 Division of Cardiology, Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
  • 6 Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, 48145 Münster, Germany; Faculty of Medicine, University of Münster, 48145 Münster, Germany.
  • 7 Division of Vascular Oncology and Metastasis, German Cancer Research Center (DKFZ-ZMBH Alliance), 69120 Heidelberg, Germany; Department of Vascular Biology and Tumor Angiogenesis (CBTM), Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany; German Cancer Consortium (DKTK), 69120 Heidelberg, Germany. Electronic address: [email protected].
PMID: 26344773 DOI: 10.1016/j.celrep.2015.08.024
Abstract

Tie1 is a mechanistically poorly characterized endothelial cell (EC)-specific Orphan Receptor. Yet, Tie1 deletion is embryonic lethal and Tie1 has been implicated in critical vascular pathologies, including atherosclerosis and tumor angiogenesis. Here, we show that Tie1 does not function independently but exerts context-dependent effects on the related receptor Tie2. Tie1 was identified as an EC activation marker that is expressed during angiogenesis by a subset of angiogenic tip and remodeling stalk cells and downregulated in the adult quiescent vasculature. Functionally, Tie1 expression by angiogenic EC contributes to shaping the tip cell phenotype by negatively regulating Tie2 surface presentation. In contrast, Tie1 acts in remodeling stalk cells cooperatively to sustain Tie2 signaling. Collectively, our data support an interactive model of Tie1 and Tie2 function, in which dynamically regulated Tie1 versus Tie2 expression determines the net positive or negative effect of Tie1 on Tie2 signaling.

Figures