title: Tissue-specific distributions of alternatively spliced human PECAM-1 isoforms.
abstract: Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a cell adhesion molecule that is highly expressed on the surface of endothelial cells and some hematopoietic cells. Its cytoplasmic domain is encoded by multiple exons, which undergo alternative splicing. Here, we demonstrate that the human PECAM-1 cytoplasmic domain undergoes alternative splicing, generating six different isoforms. RT-PCR cloning and DNA sequence analysis indicated that human tissue and endothelial cells express multiple isoforms of PECAM-1, including the full-length PECAM-1 and five other isoforms, which lack exon 12, 13, 14, or 15 or exons 14 and 15. The full-length PECAM-1 is the predominant isoform detected in human tissue and endothelial cells. This is in contrast to murine endothelium, in which the PECAM-1 isoform lacking exons 14 and 15 is the predominant isoform. The PECAM-1 isoform lacking exon 13 detected in human tissue and endothelial cells is absent in murine endothelium. The expression pattern of PECAM-1 isoforms changes during tube formation of endothelial cells on Matrigel, which may indicate specialized roles for specific isoforms of PECAM-1 during angiogenesis. The data presented here demonstrate that human PECAM-1 undergoes alternative splicing, generating multiple isoforms in vascular beds of various tissues. Therefore, the regulated expression of these isoforms may influence endothelial cell adhesive properties during angiogenesis and/or vasculogenesis.
authors.affiliation: Department of Ophthalmology, University of Wisconsin, Madison, Wisconsin 53792, USA.
authors.forename: Yongji
authors.initials: Y
authors.lastname: Wang
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Su
authors.forename: Christine M
authors.initials: CM
authors.lastname: Sorenson
authors.forename: Nader
authors.initials: N
authors.lastname: Sheibani
mesh_terms: D017398:Alternative Splicing / Q000502:physiology; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line; D003094:Collagen / Q000494:pharmacology; D004338:Drug Combinations; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007797:Laminin / Q000494:pharmacology; D051379:Mice; D008969:Molecular Sequence Data; D009928:Organ Specificity; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000096:biosynthesis / Q000235:genetics*; D020033:Protein Isoforms / Q000096:biosynthesis / Q000235:genetics; D011509:Proteoglycans / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D004338:Drug Combinations; D007797:Laminin; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D020033:Protein Isoforms; D011509:Proteoglycans; D012333:RNA, Messenger; C059485:matrigel; D003094:Collagen