The insoluble TGFBIp fraction of the cornea is covalently linked via a disulfide bond to type XII collagen.


Journal Article

TGFBIp, also known as keratoepithelin and βig-h3, is among the most abundant proteins in the human cornea, and approximately 60% is associated with the insoluble fraction following extraction in sodium dodecyl sulfate (SDS) sample buffer. TGFBIp is of particular interest because a wide range of mutations causes amyloid or fuchsinophilic crystalloid deposits in the cornea leading to visual impairment. We show that the SDS-insoluble fraction of TGFBIp from porcine and human corneas is covalently linked via a reducible bond to the NC3 domain of type XII collagen in a TGFBIp:type XII collagen stoichiometric ratio of 2:1. Because type XII collagen is anchored to striated collagen fibers of the extracellular matrix, its interaction with TGFBIp is likely to provide anchoring for cells to the extracellular matrix through the integrin binding capability of TGFBIp. Furthermore, the TGFBIp-type XII collagen molecule will affect our understanding of the molecular pathogenesis of the TGFBI-linked corneal dystrophies.

Full Text

Cited Authors

  • Runager, K; Klintworth, GK; Karring, H; Enghild, JJ

Published Date

  • April 23, 2013

Published In

Volume / Issue

  • 52 / 16

Start / End Page

  • 2821 - 2827

PubMed ID

  • 23556985

Pubmed Central ID

  • 23556985

Electronic International Standard Serial Number (EISSN)

  • 1520-4995

Digital Object Identifier (DOI)

  • 10.1021/bi400212m


  • eng

Conference Location

  • United States