|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
Journal of Cell Science, Vol 109, Issue 8 2069-2077, Copyright © 1996 by Company of Biologists
JOURNAL ARTICLES |
T Sakai, Y Furukawa, R Chiquet-Ehrismann, M Nakamura, S Kitagawa, T Ikemura and K Matsumoto
Division of Hemopoiesis, Jichi Medical School, Tochigi, Japan.
Tenascin-X has recently been shown to be a novel member of the tenascin family and its distribution is often reciprocal to that of tenascin-C in the developing mouse embryo. We have investigated the expression of tenascin-X in fibroblasts and carcinoma cells in culture. Tenascin-X protein was secreted in vitro in the conditioned media at an apparent molecular mass of approximately 450 kDa. In addition fibroblasts contained a major tenascin-X isoform of 220 kDa. On northern blots, a single major transcript with a size of approximately 13 kb was detected. No overexpression of tenascin-X protein was found in primary fibroblasts of the tenascin-C-gene knockout mice. Steroid hormone glucocorticoids, were found to downregulate tenascin-X mRNA levels and protein synthesis in fibroblasts but not carcinoma cells at physiological concentrations. None of the growth factors or cytokines examined affected the expression level of tenascin-X. As in vivo study, carcinoma cells were transplanted into nude mice. In contrast to the ubiquitous presence of tenascin-X in adult skin, expression of tenascin-X protein during tumorigenesis was found to be down-regulated considerably not only in tumor cells themselves but also in tumor stroma. These findings provide evidence that the expression of tenascin-X can be influenced by stromal-epithelial interactions. We have identified glucocorticoids as physiological inhibitors of tenascin-X and suggest that glucocorticoids may in part participate in the downregulation of tenascin-X in fibroblasts in vivo.
This article has been cited by other articles:
![]() |
E. Mackie and R. Tucker The tenascin-C knockout revisited J. Cell Sci., January 11, 1999; 112(22): 3847 - 3853. [Abstract] [PDF] |
||||
![]() |
T. Sakai, Q. Zhang, R. Fassler, and D. F. Mosher Modulation of {beta}1A Integrin Functions by Tyrosine Residues in the {beta}1 Cytoplasmic Domain J. Cell Biol., April 20, 1998; 141(2): 527 - 538. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Elefteriou, J.-Y. Exposito, R. Garrone, and C. Lethias Characterization of the Bovine Tenascin-X J. Biol. Chem., September 5, 1997; 272(36): 22866 - 22874. [Abstract] [Full Text] [PDF] |
||||