Journal of Cell Science 116, e203-e203 (2003)
Copyright © 2003 The Company of Biologists Limited
Assembling the hemidesmosome
Hemidesmosomes are rivet-like complexes that anchor epithelial cells to the
extracellular matrix (ECM), physically linking it to the cell's cytoskeleton.
They contain at least five proteins: integrin 
6ß4, which is
central to the complex and binds to laminin 5 in the ECM; plectin, a plakin
that connects the complex to keratin intermediate filaments; bullous
pemphigoid antigen 230 (BP230), another plakin; BP180; and CD151. Arnoud
Sonnenberg and co-workers have examined how these components fit together,
combining exhaustive two-hybrid analysis with assessment of the ability of
point mutants to complement genetic deficiencies in keratinocytes (see
p. 387). This has allowed them
to map pairwise interactions between the integrin, plectin, BP180 and BP230.
The studies also reveal a hierarchical assembly mechanism of unanticipated
complexity. For example, although BP230 can interact with both 6ß4
and BP180, plectin is required for incorporation of BP180, and recruitment of
BP230 occurs only if BP180 is present. These findings allow the authors to
propose an assembly model in which the integrin first interacts with plectin,
which unfolds its cytoplasmic domain, and BP180 and BP230 are then recruited
sequentially.
Related articles in JCS:
- Analysis of the interactions between BP180, BP230, plectin and the integrin 6ß4 important for hemidesmosome assembly
- Jan Koster, Dirk Geerts, Bertrand Favre, Luca Borradori, and Arnoud Sonnenberg
JCS 2003 116: 387-399.
[Abstract]
[Full Text]
