title: Vasorin, a transforming growth factor beta-binding protein expressed in vascular smooth muscle cells, modulates the arterial response to injury in vivo.
abstract: Growth factors, cell-surface receptors, adhesion molecules, and extracellular matrix proteins play critical roles in vascular pathophysiology by affecting growth, migration, differentiation, and survival of vascular cells. In a search for secreted and cell-surface molecules expressed in the cardiovascular system, by using a retrovirus-mediated signal sequence trap method, we isolated a cell-surface protein named vasorin. Vasorin is a typical type I membrane protein, containing tandem arrays of a characteristic leucine-rich repeat motif, an epidermal growth factor-like motif, and a fibronectin type III-like motif at the extracellular domain. Expression analyses demonstrated that vasorin is predominantly expressed in vascular smooth muscle cells, and that its expression is developmentally regulated. To clarify biological functions of vasorin, we searched for its binding partners and found that vasorin directly binds to transforming growth factor (TGF)-beta and attenuates TGF-beta signaling in vitro. Vasorin expression was down-regulated during vessel repair after arterial injury, and reversal of vasorin down-regulation, by using adenovirus-mediated in vivo gene transfer, significantly diminished injury-induced vascular lesion formation, at least in part, by inhibiting TGF-beta signaling in vivo. These results suggest that down-regulation of vasorin expression contributes to neointimal formation after vascular injury and that vasorin modulates cellular responses to pathological stimuli in the vessel wall. Thus, vasorin is a potential therapeutic target for vascular fibroproliferative disorders.
authors.affiliation: Division of Hematopoietic Factors and Department of Advanced Medicine, Institute of Medical Science, University of Tokyo, Tokyo 108-8639, Japan. yikeda-tky@umin.ac.jp
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ikeda
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Imai
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Kumagai
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Nosaka
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Morikawa
authors.forename: Tomoko
authors.initials: T
authors.lastname: Hisaoka
authors.forename: Ichiro
authors.initials: I
authors.lastname: Manabe
authors.forename: Koji
authors.initials: K
authors.lastname: Maemura
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakaoka
authors.forename: Takeshi
authors.initials: T
authors.lastname: Imamura
authors.forename: Kohei
authors.initials: K
authors.lastname: Miyazono
authors.forename: Issei
authors.initials: I
authors.lastname: Komuro
authors.forename: Ryozo
authors.initials: R
authors.lastname: Nagai
authors.forename: Toshio
authors.initials: T
authors.lastname: Kitamura
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001011:Aorta / Q000166:cytology / Q000293:injuries / Q000378:metabolism*; D001483:Base Sequence; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D006224:Cricetinae; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D018125:Receptors, Transforming Growth Factor beta / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D014018:Tissue Distribution; D016212:Transforming Growth Factor beta / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D008565:Membrane Proteins; D018125:Receptors, Transforming Growth Factor beta; D011993:Recombinant Fusion Proteins; D016212:Transforming Growth Factor beta; C488722:VASN protein, human