SELF-ASSEMBLY OF A RECOMBINANT AMELOGENIN PROTEIN GENERATES SUPRAMOLECULAR STRUCTURES
SELF-ASSEMBLY OF A RECOMBINANT AMELOGENIN PROTEIN GENERATES SUPRAMOLECULAR STRUCTURES
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DOI：
10.1006/jsbi.1994.1011
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发表时间：
1994-03-01
影响因子：
3
通讯作者：
SLAVKIN, HC
中科院分区：
文献类型：
--
作者：
FINCHAM, AG;MORADIANOLDAK, J;SLAVKIN, HC
釉原蛋白是细胞外有机基质的主要成分，与牙釉质中含有碳酸钙的羟基磷灰石(HAP)矿物相的成核和生长有关。釉原蛋白被认为在控制发育中的釉质晶体的大小和组织方面发挥作用。先前的研究表明，釉质蛋白表现出不寻常的可逆聚集特性。目前的研究旨在检验一种假设，即重组釉原蛋白的自组装产生的超分子结构与体内与HAP晶体生长相关的电子致密颗粒没有区别。用高分辨体积排阻色谱、原子力显微镜和透射电子显微镜对重组釉原蛋白类似物进行了分析。研究发现，釉原蛋白与蛋白质单体形成了浓度依赖的超分子聚集体。用原子力显微镜和透射电子显微镜技术对釉原蛋白进行成像，发现直径约为18 nm的球形聚集体结构与体内观察到的电子致密的釉质结构相似。我们解释这些结果表明，在体内，釉原蛋白通过蛋白质一级结构的功能基序自组装，产生特定的超分子聚集体，我们假设这些聚集体具有控制发育中的釉质微晶的超微结构组织的功能。(C)1994年学术出版社。
Amelogenin proteins are the principal constituents of the extracellular organic matrix associated with the nucleation and growth of the carbonated calcium hydroxyapatite (HAP)-containing mineral phase of dental enamel. Amelogenins are believed to function in controlling the sizes and organization of the developing enamel crystals. Previous studies have shown that enamel proteins exhibit unusual reversible aggregation properties. The present studies were designed to test the hypothesis that self-assembly of recombinant amelogenin generates supramolecular structures that are indistinguishable from the electron-dense particles associated with HAP crystal growth in vivo. A recombinant amelogenin analog of the murine 180-residue protein was analyzed by high-resolution size exclusion chromatography, atomic force (AFM), and transmission electron (TEM) microscopy. It was found that the amelogenin formed supramolecular aggregates which were in a concentration-dependent equilibrium with protein monomers. Imaging of the amelogenin by both AFM and TEM techniques revealed spherical aggregate structures of about 18 nm diameter which were seen to be similar to electron-dense enamel structures observed in vivo. We interpret these results to suggest that, in vivo, the amelogenin protein self-assembles through functional motifs of the protein primary structure, generating specific supramolecular aggregates which we hypothesize function to control the ultrastructural organization of the developing enamel crystallites. (C) 1994 Academic Press, Inc.