Author(s)

Koji Yoshida, Ah-Mee Park, Shingen Ozaki, Hiroshi Munakata

Department of Biochemistry, Kinki University Faculty of Medicine, Osaka-Sayama, Japan.
Department of Microbiology, Kinki University Faculty of Medicine, Osaka-Sayama, Japan.

Integrin α11 (ITGA11) is one of the collagen-binding integrin α chains; however, its biological significance remains unknown. To determine the functions of ITGA11, we performed a yeast two-hybrid screen using the cytoplasmic domain of ITGA11 as bait and transformed an EGY48 yeast strain with the bait-containing plasmid using the plasmid from a human lung fibroblast cDNA library. This screen identified calcium- and integrin-binding protein 1 (CIB1) as prey. Recombinant ITGA11 and CIB1 were expressed in mammalian cells and used in coimmunoprecipitation experiments, which showed that full-length ITGA11 and CIB1 are also associated in vivo. Over-expression of CIB1 in the human lung myofibroblast MRC-5 cells decreased the expression of α-smooth muscle actin and fibronectin. Using a mouse model of pulmonary fibrosis (bleomycin-treatment), we detected elevated expression of CIB1 in lung tissues compared with controls. These data suggest that CIB1 may regulate pulmonary fibrosis in concert with IT-GA11.

Calcium- and Integrin-Binding Protein 1; Fibrosis; Integrin α11; Yeast Two-Hybrid

Yoshida, K. , Park, A. , Ozaki, S. and Munakata, H. (2014) Interaction of calcium- and integrin-binding protein 1 with integrin α11 and its possible involvement in pulmonary fibrosis. Advances in Biological Chemistry, 4, 59-66. doi: 10.4236/abc.2014.41009.