کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5915200 1162790 2008 16 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Ultrastructural matrix-mineral relationships in avian eggshell, and effects of osteopontin on calcite growth in vitro
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شناسی مولکولی
پیش نمایش صفحه اول مقاله
Ultrastructural matrix-mineral relationships in avian eggshell, and effects of osteopontin on calcite growth in vitro
چکیده انگلیسی

We investigated matrix-mineral relationships in the avian eggshell at the ultrastructural level using scanning and transmission electron microscopy combined with surface-etching techniques to selectively increase topography at the matrix-mineral interface. Moreover, we investigated the distribution of osteopontin (OPN) in the eggshell by colloidal-gold immunolabeling for OPN, and assessed the effects of this protein on calcite crystal growth in vitro. An extensive organic matrix network was observed within the calcitic structure of the eggshell that showed variable, region-specific organization including lamellar sheets of matrix, interconnected fine filamentous threads, thin film-like surface coatings of proteins, granules, vesicles, and isolated proteins residing preferentially on internal {1 0 4} crystallographic faces of fractured eggshell calcite. With the exception of the vesicles and granules, these matrix structures all were immunolabeled for OPN, as were occluded proteins on the {1 0 4} calcite faces. OPN inhibited calcite growth in vitro at the {1 0 4} crystallographic faces producing altered crystal morphology and circular growth step topography at the crystal surface resembling spherical voids in mineral continuity prominent in the palisades region of the eggshell. In conclusion, calcite-occluded and interfacial proteins such as OPN likely regulate eggshell growth by inhibiting calcite growth at specific crystallographic faces and compartmental boundaries to create a biomineralized architecture whose structure provides for the properties and functions of the eggshell.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Structural Biology - Volume 163, Issue 1, July 2008, Pages 84-99
نویسندگان
, , , ,