کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2203900 1100533 2009 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Immunocytochemistry and protein analysis suggest that reptilian claws contain small high cysteine–glycine proteins
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم کشاورزی و بیولوژیک (عمومی)
پیش نمایش صفحه اول مقاله
Immunocytochemistry and protein analysis suggest that reptilian claws contain small high cysteine–glycine proteins
چکیده انگلیسی

The present study analyzes the structure and the main proteins of reptilian claws. Mature claws are formed by two to four layers of keratinocytes, a transitional layer of spindle-shaped cells and a thick corneous layer. Transitional cells elongate and merge into a compact corneous layer that is immunoreactive for beta-keratins, now indicated as sauropsid keratin-associated proteins (sKAPs). Most proteins extracted from claws in representative reptiles have a molecular weight of 13–20 kDa, an acidic to basic isoelectric point, and are identified from the positive immunoreactivity to beta-keratin antibodies. The comparative analysis between lizard and avian claw beta-keratins shows the presence of an internal region of 20 amino acids with the highest identity, indicated as core-box, within an extended 32-amino acid region with a prevalent beta-sheet secondary conformation. This region is structurally equivalent to a 32-amino acid region present in scale beta-keratins of most reptiles. Both reptilian and avian keratins contain glycine-rich regions for stabilization of the beta-keratin polymer. The N- and C-regions contain most cysteine for disulphide-bonds formation. Claw proteins contain higher amount of cysteine and glycine than other scale proteins, suggesting that claw proteins are specialized cysteine–glycine-rich proteins suited to produce a very hard corneous material.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Tissue and Cell - Volume 41, Issue 3, June 2009, Pages 180–192
نویسندگان
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