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Determinants of laminin polymerization revealed by the structure of the ?5 chain amino-terminal region.

ABSTRACT: The polymerization of laminin into a cell-associated network--a key step in basement membrane assembly--is mediated by the laminin amino-terminal (LN) domains at the tips of the three short arms of the laminin ???-heterotrimer. The crystal structure of a laminin ?5LN-LE1-2 fragment shows that the LN domain is a ?-jelly roll with several elaborate insertions that is attached like a flower head to the stalk-like laminin-type epidermal growth factor-like tandem. A surface loop that is strictly conserved in the LN domains of all ?-short arms is required for stable ternary association with the ?- and ?-short arms in the laminin network.

SUBMITTER: Hussain SA

PROVIDER: S-EPMC3059903 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Determinants of laminin polymerization revealed by the structure of the α5 chain amino-terminal region.

Hussain Sadaf-Ahmahni SA Carafoli Federico F Hohenester Erhard E

EMBO reports 20110211 3

The polymerization of laminin into a cell-associated network--a key step in basement membrane assembly--is mediated by the laminin amino-terminal (LN) domains at the tips of the three short arms of the laminin αβγ-heterotrimer. The crystal structure of a laminin α5LN-LE1-2 fragment shows that the LN domain is a β-jelly roll with several elaborate insertions that is attached like a flower head to the stalk-like laminin-type epidermal growth factor-like tandem. A surface loop that is strictly cons ...[more]

PMID: 21311558

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