Tonofibril

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Citation bot (talk | contribs) at 18:03, 3 December 2019 (Add: pmid. Removed URL that duplicated unique identifier. | You can use this bot yourself. Report bugs here.| Activated by User:Nemo bis | via #UCB_webform). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Tonofibrils are cytoplasmic protein structures in epithelial tissues that converge at desmosomes and hemidesmosomes.[1] They consist of fine fibrils in epithelial cells that are anchored to the cytoskeleton.[2] They were discovered by Rudolf Heidenhain, and first described in detail by Louis-Antoine Ranvier in 1897.[3]

Composition

Tonofilaments are keratin intermediate filaments that makes up tonofibrils in the epithelial tissue. In epithelial cells, tonofilaments loop through desmosomes. Electron microscopy has advanced now to illustrate the Tonofilaments more clearly[1].

The protein filaggrin is believed to have an important role in holding them together as tonofibrils. This protein is known to interact with intermediate filaments, specifically keratins. It is synthesized as a giant Precursor protein, profilaggrin (>400 kDA in humans). When the filaggrin binds to keratin intermediate filaments, it causes aggregation in macrofibrils.[2]

References

  1. ^ a b "tonofibril" at Dorland's Medical Dictionary
  2. ^ a b Sandilands, Aileen; Sutherland, Calum; Irvine, Alan D.; McLean, W. H. Irwin (2009-05-01). "Filaggrin in the frontline: role in skin barrier function and disease". J Cell Sci. 122 (9): 1285–1294. doi:10.1242/jcs.033969. ISSN 0021-9533. PMC 2721001. PMID 19386895.
  3. ^ Charles, Arwyn; Smiddy, F. G. (1957-09-01). "The Tonofibrils of the Human Epidermis1". Journal of Investigative Dermatology. 29 (5): 327–338. doi:10.1038/jid.1957.108. ISSN 0022-202X. PMID 13502588.

External links