Prostaglandins & other Lipid Mediators 73 (2004) 141–150 Constitutive expression of the S1P 1 receptor in adult tissues Sung-Suk Chae a , Richard L. Proia b , Timothy Hla a,∗ a Center for Vascular Biology, Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030-3501, USA b Genetics of Disease and Development Branch, NIDDK, NIH, Bethesda, MD, USA Received 25 December 2003; received in revised form 7 January 2004; accepted 8 January 2004 Abstract S1P 1 (also known as EDG-1) is a G-protein coupled receptor for the bioactive lipid, sphingosine- 1-phosphate (S1P). Activation of S1P 1 receptor in endothelial cells induces diverse cellular effects, including cell proliferation, survival, migration and morphogenesis. Recent in vivo studies showed that the S1P 1 receptor is required in vascular maturation during development. While a number of studies reported a functional role of S1P 1 in vascular system and the presence of S1P 1 transcripts in various mouse organs, tissue distribution of S1P 1 has not been fully defined. In this study, we determined the expression pattern of S1P 1 by -galactosidase reporter gene expression, which is knocked into the S1P 1 locus. We show that S1P 1 is widely expressed in various cell types of adult mouse tissues, suggesting a regulatory role of this receptor in numerous physiological processes in both vascular and non-vascular tissues. © 2004 Elsevier Inc. All rights reserved. Keywords: Sphingosine-1-phosphate; EDG-1; Gene expression 1. Introduction Sphingosine-1-phosphate (S1P), a bioactive lipid molecule, is produced from the metabo- lism of sphingomyelin. S1P acts extracellularly as a ligand via the specific G protein-coupled Abbreviations: S1P, sphingosine-1-phosphate; VEGF, vascular endothelial growth factor ∗ Corresponding author. Tel.: +1-860-679-4128; fax: +1-860-679-1201. E-mail address: hla@nso2.uchc.edu (T. Hla). 1098-8823/$ – see front matter © 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.prostaglandins.2004.01.006