Structural basis for interactions between tenascins and lectican C-type lectin domains: evidence for a crosslinking role for tenascins.

Summary, in English

The C-terminal G3 domains of lecticans mediate crosslinking to diverse extracellular matrix (ECM) proteins during ECM assembly, through their C-type lectin (CLD) subdomains. The structure of the rat aggrecan CLD in a Ca(2+)-dependent complex with fibronectin type III repeats 3-5 of rat tenascin-R provides detailed support for such crosslinking. The CLD loops bind Ca2+ like other CLDs, but no carbohydrate binding is observed or possible. This is thus the first example of a direct Ca(2+)-dependent protein-protein interaction of a CLD. Surprisingly, tenascin-R does not coordinate the Ca2+ ions directly. Electron microscopy confirms that full-length tenascin-R and tenascin-C crosslink hyaluronan-aggrecan complexes. The results are significant for the binding of all lectican CLDs to tenascin-R and tenascin-C. Comparison of the protein interaction surface with that of P-selectin in complex with the PGSL-1 peptide suggests that direct protein-protein interactions of Ca(2+)-binding CLDs may be more widespread than previously appreciated.

• Författare: Anna Lundell; Anders Olin; Matthias Mörgelin; Salam Al-Karadaghi; Anders Aspberg; Derek Logan
• Avdelning/ar: Infektionsmedicin; Biokemi och Strukturbiologi; Institutionen för experimentell medicinsk vetenskap
• Publiceringsår: 2004
• Språk: Engelska
• Sidor: 1495-1506
• Publikation/Tidskrift/Serie: Structure
• Volym: 12
• Issue: 8
• Länkar: http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=15296743&dopt=Abstract; http://dx.doi.org/10.1016/j.str.2004.05.021
• Dokumenttyp: Artikel i tidskrift
• Förlag: Cell Press
• Ämne: Infectious Medicine; Cell and Molecular Biology
• Status: Published
• ISBN/ISSN/Övrigt: ISSN: 0969-2126