Different domains in nidogen-1 and nidogen-2 drive basement membrane formation in skin organotypic cocultures

Research output: Contribution to journalJournal articlesResearch

Authors

  • Manuela Bechtel
  • Manuel V Keller
  • Wilhelm Bloch
  • Takako Sasaki
  • Petra Boukamp
  • Frank Zaucke
  • Mats Paulsson
  • Roswitha Nischt

Research units

Details

Nidogen-1 and nidogen-2 are homologous proteins found in all basement membranes (BMs). They show comparable binding activities in vitro and partially redundant functions in vivo. Previously, we showed that in skin organotypic cocultures, BM formation was prevented in the absence of nidogens and that either nidogen was able to rescue this failure. We now dissected the two nidogens to identify the domains required for BM deposition. For that purpose, HaCaT cells were grown on collagen matrices containing nidogen-deficient, murine fibroblasts. After addition of nidogen-1 or nidogen-2 protein fragments comprising different binding domains, BM deposition was analyzed by immunofluorescence and electron microscopy. We could demonstrate that the rod-G3 domain of nidogen-2 was sufficient to achieve deposition of BM components at the epidermal-collagen interface. In contrast, for nidogen-1, both the G2 and G3 domains were required. Immunoblot analysis confirmed that all BM components were present in comparable amounts under all culture conditions. This finding demonstrates that nidogens, although homologous proteins, exert their effect on BM assembly through different binding domains, which may in turn result in alterations of BM structure and functions, thus providing an explanation for the phenotypical differences observed between nidogen-1 and -2 deficient mice.

Original languageEnglish
JournalFASEB journal : official publication of the Federation of American Societies for Experimental Biology
Volume26
Issue number9
Pages (from-to)3637-3648
Number of pages12
DOIs
Publication statusPublished - 01.09.2012

ID: 66957

DOI

View graph of relations