Dataset Information

CapZ-lipid membrane interactions: a computer analysis.

ABSTRACT:

Background

CapZ is a calcium-insensitive and lipid-dependent actin filament capping protein, the main function of which is to regulate the assembly of the actin cytoskeleton. CapZ is associated with membranes in cells and it is generally assumed that this interaction is mediated by polyphosphoinositides (PPI) particularly PIP2, which has been characterized in vitro.

Results

We propose that non-PPI lipids also bind CapZ. Data from computer-aided sequence and structure analyses further suggest that CapZ could become partially buried in the lipid bilayer probably under mildly acidic conditions, in a manner that is not only dependent on the presence of PPIs. We show that lipid binding could involve a number of sites that are spread throughout the CapZ molecule i.e., alpha- and beta-subunits. However, a beta-subunit segment between residues 134-151 is most likely to be involved in interacting with and inserting into lipid membrane due to a slighly higher ratio of positively to negatively charged residues and also due to the presence of a small hydrophobic helix.

Conclusion

CapZ may therefore play an essential role in providing a stable membrane anchor for actin filaments.

SUBMITTER: Smith J

PROVIDER: S-EPMC1564000 | biostudies-literature | 2006 Aug

REPOSITORIES: biostudies-literature

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Publications

CapZ-lipid membrane interactions: a computer analysis.

Smith James J Diez Gerold G Klemm Anna H AH Schewkunow Vitali V Goldmann Wolfgang H WH

Theoretical biology & medical modelling 20060816

<h4>Background</h4>CapZ is a calcium-insensitive and lipid-dependent actin filament capping protein, the main function of which is to regulate the assembly of the actin cytoskeleton. CapZ is associated with membranes in cells and it is generally assumed that this interaction is mediated by polyphosphoinositides (PPI) particularly PIP2, which has been characterized in vitro.<h4>Results</h4>We propose that non-PPI lipids also bind CapZ. Data from computer-aided sequence and structure analyses furt ...[more]

PMID: 16914033

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Dataset Information

CapZ-lipid membrane interactions: a computer analysis.

Background

Results

Conclusion

Publications

CapZ-lipid membrane interactions: a computer analysis.

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