부산대학교 도서관

Abstract Background Retinoic acid, a metabolic product of retinol, is essential for craniofacial morphogenesis. Transthyretin (TTR) is a plasma protein delivering retinol to tissues. We produced several transgenic mouse lines using the human mutant TTR (hTTR Met30 ) gene to establish a mouse model of familial amyloidotic polyneuropathy. One of the lines showed an autosomal dominant inheritance of n aso-max illary deformity termed Nax . Results: The Nax malformation was characterized by a hypoplastic developmental defect of the frontonasal region. Homozygous mice with higher transgene expressions showed more severe phenotypes, but a subline, in which the copy number and expression of the transgene was reduced, showed a normal phenotype, indicating that the hTTR Met30 expression caused the malformation. Nax mice began to express the hTTR Met30 gene in the nasal placode from embryonic day 10.5 (E10.5), which was 2 days earlier than in the other transgenic lines with a normal phenotype. Excessive cell death was observed in the nasal placode of the E10.5 Nax embryos. In addition, the forced expression of hTTR Met30 in the nasal placode of transgenic mice resulted in similar phenotypes. Conclusion: The expression of the hTTR Met30 gene in the nasal placode at E10.5 induced apoptotic cell death, leading to hypoplastic deformity in the frontonasal region. [ABSTRACT FROM AUTHOR]