| First Author | Fontana L | Year | 2005 |
| Journal | FASEB J | Volume | 19 |
| Issue | 13 | Pages | 1798-808 |
| PubMed ID | 16260650 | Mgi Jnum | J:102667 |
| Mgi Id | MGI:3607891 | Doi | 10.1096/fj.05-4134com |
| Citation | Fontana L, et al. (2005) Fibronectin is required for integrin alphavbeta6-mediated activation of latent TGF-beta complexes containing LTBP-1. FASEB J 19(13):1798-808 |
| abstractText | Transforming growth factor-betas (TGF-beta) are secreted as latent complexes consisting of the TGF-beta dimer, the TGF-beta propeptide dimer, and the latent TGF-beta binding protein (LTBP). Although the bonds between TGF-beta and its propeptide are cleaved intracellulary, the propeptide associates with TGF-beta by electrostatic interactions, thereby conferring latency to the complex. We reported that a specific sequence of LTBP-1 is required for latent TGF-beta activation by the integrin alphavbeta6. Here we describe a 24 amino acid sequence from the hinge domain required for activation. The LTBP-1 polypeptide rL1N, which includes the hinge, associates with fibronectin in binding assays. We present evidence that fibronectin null cells minimally activate latent TGF-beta and poorly incorporate the active hinge sequence into their matrix. In addition, cells missing the fibronectin receptor alpha5beta1 exhibit defective activation of latent TGF-beta by alphavbeta6 and decreased matrix incorporation. The results indicate specificity for integrin-mediated latent TGF-beta activation that include unique sequences in LTBP-1 and an appropriate matrix molecule. |
