RRC ID 4370
Author Osawa M, Kenmotsu S, Masuyama T, Taniguchi K, Uchida T, Saito C, Ohshima H.
Title Rat wct mutation prevents differentiation of maturation-stage ameloblasts resulting in hypo-mineralization in incisor teeth.
Journal Histochem Cell Biol
Abstract A recent study provided genetic and morphological evidence that rat autosomal-recessive mutation, whitish chalk-like teeth (wct), induced tooth enamel defects resembling those of human amelogenesis imperfecta (AI). The wct locus maps to a specific interval of rat chromosome 14 corresponding to human chromosome 4q21 where the ameloblastin and enamelin genes exist, although these genes are not included in the wct locus. The effect of the wct gene mutation on the enamel matrix synthesis and calcification remains to be elucidated. This study clarifies how the wct gene mutation influences the synthesis of enamel matrix and its calcification by immunocytochemistry for amelogenin, ameloblastin and enamelin, and by electron probe micro-analysis (EPMA). The immunoreactivity for enamel proteins such as amelogenin, ameloblastin, and enamelin in the ameloblasts in the homozygous teeth was the same as that in the heterozygous teeth from secretory to transitional stages, although the homozygous ameloblasts became detached from the enamel matrix in the transitional stage. The flattened ameloblasts in the maturation stage of the homozygous samples contained enamel proteins in their cytoplasm. Thus, the wct mutation was found to prevent the morphological transition of ameloblasts from secretory to maturation stages without disturbing the synthesis of enamel matrix proteins, resulting in the hypo-mineralization of incisor enamel and cyst formation between the enamel organ and matrix. This mutation also prevents the transfer of iron into the enamel.
Volume 128(3)
Pages 183-93
Published 2007-9-1
DOI 10.1007/s00418-007-0297-3
PMID 17636316
MeSH Ameloblasts / pathology* Animals Cell Differentiation / genetics Chromosome Disorders / genetics* Dental Enamel Proteins / biosynthesis Disease Models, Animal Electron Probe Microanalysis / methods Immunohistochemistry Incisor / pathology* Male Mutation Rats Rats, Mutant Strains Tomography, X-Ray Computed Tooth Demineralization / pathology* X-Rays
IF 3.418
Times Cited 6
WOS Category MICROSCOPY CELL BIOLOGY
Resource
Rats WT/Jtt(strainID=476)