Journal of Biochemistry Advance Access originally published online on July 7, 2006
Journal of Biochemistry 2006 140(2):193-200; doi:10.1093/jb/mvj146
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© 2006 The Japanese Biochemical Society.
Regular Paper |
Significant Decrease in Tropoelastin Gene Expression in Fibroblasts from a Japanese Costello Syndrome Patient with Impaired Elastogenesis and Enhanced Proliferation
1 Department of Medicinal Biotechnology, Institute for Medicinal Resources, Graduate School of Pharmaceutical Sciences, The University of Tokushima, Tokushima 770-8505; 2 Department of Pediatrics, Akita University of Medical School, Akita 010-8543; 3 Department of Clinical Genetics, The Tokyo Metropolitan Institute of Medical Science, Tokyo Metropolitan Organization for Medical Research, Tokyo 113-8613; and 4 CREST, JST, Saitama 332-0012
* To whom correspondence should be addressed. Tel/Fax: +81-88-633-7290, E-mail: kitoh{at}ph.tokushima-u.ac.jp
Costello syndrome is a connective tissue disorder associated with sparse, thin, and fragmented elastic fibers in tissues. In this study we demonstrated a significant decrease in the expression of tropoelastin mRNA in fibroblasts derived from a Japanese Costello syndrome patient with impaired elastogenesis and enhanced proliferation. In contrast, there were no changes in expression of the Harvey ras (HRAS), fibrillin-1, fibulin-5, microfibril-associated glycoprotein-1 (MAGP-1), lysyl oxidase (LOX), or 67-kDa non-integrin elastin-binding protein (EBP) gene. The proliferative activity of the Costello fibroblasts was about 4-fold higher than that of the normal and pathological control ones. However, no mutations were detected in the coding region of HRAS mRNA. Transduction of the bovine tropoelastin (bTE) gene with the lentiviral vector restored the elastic fiber formation and decreased the growth rate in the Costello fibroblasts. These results strongly suggest that the defect of human tropoelastin (hTE) gene expression should induce the impaired elastogenesis and enhanced proliferation of Costello fibroblasts, and that a primary cause other than the HRAS gene mutation should contribute to the pathogenesis in the present Costello case.