Structural, spatial, and temporal features guiding amelogenins transformation of calcium phosphate into enamel

指导釉原蛋白将磷酸钙转化为牙釉质的结构、空间和时间特征

基本信息

批准号：
10471432
负责人：
Wendy J Shaw
金额：
$ 48.27万
依托单位：
BATTELLE PACIFIC NORTHWEST LABORATORIES
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-08-19 至 2026-07-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10471432
关键词：
3-Dimensional Adsorption Affect Amelogenesis Imperfecta Amino Acid Substitution Amino Acids Atomic Force Microscopy Binding Coupled Crystallization Dental Enamel Development Disease Enamel Formation Extracellular Matrix Goals Growth Hydroxyapatites In Situ In Vitro Individual Ions Knockout Mice Knowledge Lead Maps Microscopic Minerals Modification Molecular Morphology Mus Mutation N-terminal Nanosphere Natural regeneration Nature Needles Outcome Persons Phase Phase Transition Phenotype Process Property Proteins Raman Spectrum Analysis Research Roentgen Rays Role Scanning Site Spatial Distribution Spectrum Analysis Structure System Techniques Therapeutic Time Tissues Ursidae Family Variant Vertebrates Work X ray microscopy amelogenin base biomineralization calcium phosphate crystallinity design falls in vivo insight mineralization mouse model nanoscale particle prevent protein distribution protein protein interaction protein structure repaired solid state nuclear magnetic resonance spatial relationship tomography tool transmission process

项目摘要

Project Summary The goal of the proposed work is to develop a molecular level, structural understanding of the role of amelogenin in directing the hierarchical growth of enamel. Enamel is one of the hardest biominerals known, and is hierarchically structured to prevent crack propagation, allowing it to last many people a lifetime. However, naturally occurring diseases or damage do occur to enamel and our current therapies fall far short of nature made enamel. Over the past decade we have come to understand that amelogenin assembles into quaternary structures as oligomers containing 12 proteins, units which further assemble into nanospheres. These assemblies, the molecular level interactions governing them, their interactions with calcium phosphate, and their role in mineral phase transformations, are not well understood for enamel formation. We do know that the protein amelogenin, the predominant protein in the forming enamel milieu, is critical in formation based on amelogenin null mouse models showing severely damaged enamel phenotypes. Protein structure often dictates function, yet we have only begun to reveal the structure of amelogenin. Further, the mineral in the enamel milieu begins as ions, and transitions through an amorphous stage prior to becoming elongated, crystallized HAP needles. Both in vivo and in vitro studies have demonstrated that amelogenin controls this phase transformation process, but the structural, spatial, and temporal aspects of this process are not understood. In our proposed work, we bring a set of advanced characterization techniques to an in vitro system simulating developing enamel to evaluate the structure of amelogenin when interacting with calcium phosphates, to understand the spatial distribution of amelogenin around developing calcium phosphate mineral ribbons, and to develop a molecular level view of the transformation process from calcium phosphate clusters, through the amorphous phase, on to crystalline HAP. This suite of techniques has never been brought to bear on understanding the challenge of enamel growth and will result in an understanding of the development of enamel that is currently lacking. The results of this work are relevant to biomineralization systems in general and may ultimately inform more robust therapeutics for enamel replacements.

项目摘要拟议工作的目的是发展分子水平，结构上对指导牙釉质的分层生长时，氨基蛋白原。搪瓷是最难的生物矿物之一，并且是层次结构的，以防止裂纹繁殖，从而使许多人终生持续。但是，牙釉质确实会发生自然发生的疾病或损害大自然制造了搪瓷。在过去的十年中第四纪结构作为含有12种蛋白质的低聚物，这些单位进一步组装成纳米球。这些组件，分子水平的相互作用来控制它们，它们与磷酸钙的相互作用，并且它们在矿物相变中的作用尚不为搪瓷形成而被很好地理解。我们知道蛋白质氨基蛋白是形成搪瓷环境中主要蛋白质的蛋白质蛋白，在形成中至关重要基于氨基蛋白蛋白零小鼠模型，显示了严重受损的搪瓷表型。蛋白质结构通常决定功能，但我们才开始揭示氨基蛋白素的结构。此外，矿物搪瓷环境始于离子，并在伸长之前通过无定形阶段过渡，结晶的HAP针。体内和体外研究都表明，氨基蛋白素可以控制这一点相变过程，但是该过程的结构，空间和时间方面不是理解。在我们提出的工作中，我们为体外系统带来了一系列高级表征技术模拟开发搪瓷以评估与钙相互作用时的结构磷酸盐，了解蛋白质蛋白周围磷酸钙矿物质周围的空间分布丝带，并开发从磷酸钙簇转化过程的分子水平视图，穿过无定形阶段，到达结晶HAP。这套技术从未被带来了解搪瓷增长的挑战，并将导致理解目前缺乏的搪瓷。这项工作的结果通常与生物矿化系统有关并最终可能会为牙釉质替代品提供更强大的治疗剂。