The C-terminus of the {gamma}2 chain but not of the {beta}3 chain of laminin-332 is indirectly but indispensably necessary for integrin-mediated cell reactions

Journal Article · Fri Feb 01 00:00:00 EST 2008 · Experimental Cell Research

DOI:https://doi.org/10.1016/j.yexcr.2007.10.027· OSTI ID:21045933

Navdaev, Alexei ^[1]; Heitmann, Vanessa ^[2]; Santana Evangelista, Karla de ^[1]; Moergelin, Matthias ^[3]; Wegener, Joachim ^[2]

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1. Institute for Physiological Chemistry, Muenster University Hospital, 48149 Muenster (Germany)
2. Institute for Biochemistry, Muenster University, 48149 Muenster (Germany)
3. University of Lund, Department of Clinical Sciences, Division of Infection Medicine, 22184 Lund (Sweden)

Using a recombinant mini-laminin-332, we showed that truncation of the three C-terminal amino acids of the {gamma}2 chain, but not of the C-terminal amino acid of the {beta}3 chain, completely abolished {alpha}3{beta}1 integrin binding and its cellular functions, such as attachment and spreading. However, a synthetic peptide mimicking the {gamma}2 chain C-terminus did not interfere with {alpha}3{beta}1 integrin binding or cell adhesion and spreading on laminin-332 as measured by protein interaction assays and electric cell-substrate impedance sensing. Nor was the soluble peptide able to restore the loss of integrin-mediated cell adhesiveness to mini-laminin-332 after deletion of the {gamma}2 chain C-terminus. These findings spoke against the hypothesis that the {gamma}2 chain C-terminus of laminin-332 is a part of the {alpha}3{beta}1 integrin interaction site. In addition, structural studies with electron microscopy showed that truncation of the {gamma}2 chain C-terminus opened up the compact supradomain structure of LG1-3 domains. Thus, by inducing or stabilizing an integrin binding-competent conformation or array of the LG1-3 domains, the {gamma}2 chain C-terminus plays an indirect but essential role in laminin-332 recognition by {alpha}3{beta}1 integrin and, hence, its cellular functions.

• OSTI ID: 21045933
• Journal Information: Experimental Cell Research, Vol. 314, Issue 3; Other Information: DOI: 10.1016/j.yexcr.2007.10.027; PII: S0014-4827(07)00521-6; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0014-4827
• Country of Publication: United States
• Language: English

Related Subjects

60 APPLIED LIFE SCIENCES
AMINO ACIDS
ELECTRON MICROSCOPY
IMPEDANCE
MONOCLONAL ANTIBODIES
PEPTIDES
SUBSTRATES