title: DICAM, a novel dual immunoglobulin domain containing cell adhesion molecule interacts with alphavbeta3 integrin.
abstract: Immunoglobulin (Ig) superfamily members are abundant with diverse functions including cell adhesion in various tissues. Here, we identified and characterized a novel adhesion molecule that belongs to the CTX protein family and named as DICAM (Dual Ig domain containing cell adhesion molecule). DICAM is a type I transmembrane protein with two V-type Ig domains in the extracellular region and a short cytoplasmic tail of 442 amino acids. DICAM is found to be expressed ubiquitously in various organs and cell lines. Subcellular localization of DICAM was observed in the cell-cell contact region and nucleus of cultured epithelial cells. Cell-cell contact region was colocalized with tight junction protein, ZO-1. The DICAM increased MDCK cell adhesion to 60% levels of fibronectin. DICAM mediated cell adhesion was specific for the alphavbeta3 integrin; other integrins, alpha2, alpha5, beta1, alpha2beta1, alpha5beta1, were not involved in cell adhesion. In identifying the interacting domain of DICAM with alphavbeta3, the Ig domain 2 showed higher cell adhesion activity than that of Ig domain 1. Although RGD motif in Ig domain 2 was engaged in cell adhesion, it was not participated in DICAM-alphavbeta3 mediated cell adhesion. Furthermore, differentially expressing DICAM stable cells showed well correlated cell to cell adhesion capability with integrin beta3-overexpressing cells. Collectively, these results indicate that DICAM, a novel dual Ig domain containing adhesion molecule, mediates cell adhesion via alphavbeta3 integrin.
authors: Department of Biochemistry and Cell Biology, Kyungpook National University, Daegu, Republic of Korea.
authors: Youn-Kwan
authors: YK
authors: Jung
authors: Jung-Suk
authors: JS
authors: Jin
authors: Jae-Hwan
authors: JH
authors: Jeong
authors: Hyun-Nam
authors: HN
authors: Kim
authors: Na-Rae
authors: NR
authors: Park
authors: Je-Yong
authors: JY
authors: Choi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002448:Cell Adhesion / Q000502:physiology*; D015815:Cell Adhesion Molecules / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D006801:Humans; D007136:Immunoglobulins / Q000378:metabolism; D039302:Integrin alphaVbeta3 / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D014018:Tissue Distribution
chemical_list: D015815:Cell Adhesion Molecules; C530913:DICAM protein, mouse; D007136:Immunoglobulins; D039302:Integrin alphaVbeta3; D008565:Membrane Proteins