Stratum corneum keratin structure, function, and formation: the cubic rod-packing and membrane templating model.
Details
Serval ID
serval:BIB_32862
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Stratum corneum keratin structure, function, and formation: the cubic rod-packing and membrane templating model.
Journal
Journal of Investigative Dermatology
ISSN
0022-202X
Publication state
Published
Issued date
2004
Volume
123
Number
4
Pages
715-732
Language
english
Abstract
A new model for stratum corneum keratin structure, function, and formation is presented. The structural and functional part of the model, which hereafter is referred to as "the cubic rod-packing model", postulates that stratum corneum keratin intermediate filaments are arranged according to a cubic-like rod-packing symmetry with or without the presence of an intracellular lipid membrane with cubic-like symmetry enveloping each individual filament. The new model could account for (i) the cryo-electron density pattern of the native corneocyte keratin matrix, (ii) the X-ray diffraction patterns, (iii) the swelling behavior, and (iv) the mechanical properties of mammalian stratum corneum. The morphogenetic part of the model, which hereafter is referred to as "the membrane templating model", postulates the presence in cellular space of a highly dynamic small lattice parameter (<30 nm) membrane structure with cubic-like symmetry, to which keratin is associated. It further proposes that membrane templating, rather than spontaneous self-assembly, is responsible for keratin intermediate filament formation and dynamics. The new model could account for (i) the cryo-electron density patterns of the native keratinocyte cytoplasmic space, (ii) the characteristic features of the keratin network formation process, (iii) the dynamic properties of keratin intermediate filaments, (iv) the close lipid association of keratin, (v) the insolubility in non-denaturating buffers and pronounced polymorphism of keratin assembled in vitro, and (vi) the measured reduction in cell volume and hydration level between the stratum granulosum and stratum corneum. Further, using cryo-transmission electron microscopy on native, fully hydrated, vitreous epidermis we show that the subfilametous keratin electron density pattern consists, both in corneocytes and in viable keratinocytes, of one axial subfilament surrounded by an undetermined number of peripheral subfilaments forming filaments with a diameter of approximately 8 nm.
Keywords
Adult, Cell Membrane, Cryoelectron Microscopy, Epidermis, Humans, Intermediate Filaments, Keratinocytes, Keratins, Male, X-Ray Diffraction
OAI-PMH
Pubmed
Web of science
Open Access
Yes
Create date
19/11/2007 12:31
Last modification date
20/08/2019 13:18