Cornified cell envelope

Steinert, P. M., and Marekov, L. N. (1997). Direct evidence that involucrin is a major early isopeptide crosslinked component of the keratinocyte cornified cell envelope./ Biol. Chem. 272, 2021-2030. 

Aho, S., Li, K., Ryoo, Y., McGee, C., Ishida-Yamamoto, A., Uitto,J., and Klement, J. F. (2004). Periplakin gene targeting reveals a constituent of the cornified cell envelope dispensable for normal mouse development. Mol. Cell. Biol. 24, 6410-6418. 

Lee, S.-C., Kim, I.-G., Marekov, L. N., O Keefe, E. J., Parry, D. A. D., and Steinert, P. M. (1993). The structure of human trichohyalin Potential multiple roles as a functional EF-hand-like calcium-binding protein, a cornified cell envelope precursor, and an intermediate filament-associated (cross-linking) protein. / Biol. Chem. 268, 12164-12176. 

Simon, M., Haftek, M., Sebbag, M., Montezin, M., Girbal-Neuhauser, E., Schmitt, D., and Serre, G. (1996). Evidence that filaggrin is a component of cornified cell envelopes in human plantar epidermis. Biochem. J. 317, 173-177. 

Hohl, D., M. Huber, and E. Frenk. 1993. Analysis of the cornified cell envelope in lamellar... 

FIGURE 4.3 High magnification transmission electron micrographs of multilamellar membrane structures in the intercellular space of the cornified part of human epidermis. (A) cryo-electron micrograph of vitreous section. (B, C) conventional electron micrographs of resin embedded sections. The cell plasma membranes appear as 3.8 nm wide bilayers in (A) (open white arrow). A 16 nm broad zone of electron dense material, the cornified cell envelope (white asterix), is directly apposed to the cytoplasmic side of the bilayer plasma membranes in the native sample (A) (open white arrow). Scale bar 50 nm (A). Scale bars 25 nm (B, C) adapted from measures given in Swartzendruber et al. (1989). (A) reprinted from Norlen (2003). With permission from Blackwell Science Publications. (B, C) reprinted from Swartzendruber et al. (1989). With permission from Blackwell Science Publications. 

Ishida-Yamamoto, A. and Iizuka, H., Structural organization of cornified cell envelopes and alterations in inherited skin disorders, Exp. Dermatol., 1, 1-10, 1998. 

Steinert, P.M. and Marekov, L.N. The proteins elafin, filaggrin, keratin intermediate filaments, loricrin, and small proline-rich proteins are isodipeptide cross-linked components of the human cornified cell-envelope, J. Biol. Chem., 270, 17702, 1995. 

Candi, E. et al. A highly conserved lysine residue on the head domain of type II keratins is essential for the attachment of keratin intermediate filaments to the cornified cell envelope through isodipeptide crosslinking by transglutaminase, Proc. Natl Acad. Sci. USA, 95, 2067, 1998. 

Harding, C.R. et al. The cornified cell envelope an important marker of stratum corneum maturation in healthy and dry skin, Ini. J. Cosmet. Sci., 25, 157, 2003... 

Each corneocyte corresponds to a water-insoluble protein complex made primarily of a highly organized keratin microfibrillar matrix. This structure is encapsulated in a protein and lipid-enriched shell. This cornified cell envelope shows differences in maturation among corneocytes. Specific probes allow to distinguish two distinct types of cornified cell envelopes, which have been called fragile and rigid, or immature and mature. 2 4 5... 

The cornified cell envelope is the outermost layer of a corneocyte, and mainly consists of tightly bundled keratin filaments aligned parallel to the main face of the corneocyte. The envelope consists of both protein and lipid components in that the lipid is attached covalently to the protein envelope. The envelope lies adjacent to the interior surface of the plasma membrane. " The corneocyte protein envelope appears to play an important role in the structural assembly of the intercellular lipid lamellae of the stratum corneum. The corneocyte possesses a chemically bound lipid envelope comprised of A-co-hydroxyceramides, which are ester linked to the numerous glutamate side chains provided possibly by both the ot-helical conformation and p-sheet conformation of involucrin in the envelope protein matrix. In the absence of A-oo-hydro-xyceramides, the stratum corneum intercellular lipid lamellae were abnormal and permeability barrier function was disrupted. 

About 25 different human genes encode the keratins of skin and other soft tissues. Others specify the keratins of hair and nails.Both of these hard tissues as well as claws, hoofs, beaks, horns, scales, quills, and feathers are largely keratin. However, there are additional constituents. During the final stages of keratinocyte differentiation a 15-nm-thick crosslinked sheath of protein, the cornified cell envelope (CE), forms beneath the plasma membrane. Crosslinkages between keratin and other proteins are formed by the action of transglutaminases. " ... 

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