Structural highlights
Function
[VILI_CHICK] Epithelial cell-specific Ca(2+)-regulated actin-modifying protein that modulates the reorganization of microvillar actin filaments. Plays a role in the actin nucleation, actin filament bundle assembly, actin filament capping and severing. Binds phosphatidylinositol 4,5-bisphosphate (PIP2) and lysophosphatidic acid (LPA); binds LPA with higher affinity than PIP2. Binding to LPA increases its phosphorylation by SRC and inhibits all actin-modifying activities. Binding to PIP2 inhibits actin-capping and -severing activities but enhances actin-bundling activity. Regulates the intestinal epithelial cell morphology, cell invasion, cell migration and apoptosis. Protects against apoptosis induced by dextran sodium sulfate (DSS) in the gastrointestinal epithelium. Appears to regulate cell death by maintaining mitochondrial integrity. Enhances hepatocyte growth factor (HGF)-induced epithelial cell motility, chemotaxis and wound repair (By similarity). Its actin-bundling activity is inhibited by tropomyosin.[1] [2]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Villin-type headpiece domains are approximately 70 amino acid modular motifs found at the C terminus of a variety of actin cytoskeleton-associated proteins. The headpiece domain of villin, a protein found in the actin bundles of the brush border epithelium, is of interest both as a compact F-actin binding domain and as a model folded protein. We have determined the high-resolution crystal structures of chicken villin headpiece (HP67) at 1.4 A resolution as well as two mutants, R37A and W64Y, at 1.45 and 1.5 A resolution, respectively. Replacement of R37 causes a 5-fold reduction in F-actin binding affinity in sedimentation assays. Replacement of W64 results in a much more drastic reduction in F-actin binding affinity without significant changes in headpiece structure or stability. The detailed comparison of these crystal structures with each other and to our previously determined NMR structures of HP67 and the 35-residue autonomously folding subdomain in villin headpiece, HP35, provides the details of the headpiece fold and further defines the F-actin binding site of villin-type headpiece domains.
High-resolution crystal structures of villin headpiece and mutants with reduced F-actin binding activity.,Meng J, Vardar D, Wang Y, Guo HC, Head JF, McKnight CJ Biochemistry. 2005 Sep 13;44(36):11963-73. PMID:16142894[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Burgess DR, Broschat KO, Hayden JM. Tropomyosin distinguishes between the two actin-binding sites of villin and affects actin-binding properties of other brush border proteins. J Cell Biol. 1987 Jan;104(1):29-40. PMID:3793760
- ↑ de Arruda MV, Bazari H, Wallek M, Matsudaira P. An actin footprint on villin. Single site substitutions in a cluster of basic residues inhibit the actin severing but not capping activity of villin. J Biol Chem. 1992 Jun 25;267(18):13079-85. PMID:1618806
- ↑ Meng J, Vardar D, Wang Y, Guo HC, Head JF, McKnight CJ. High-resolution crystal structures of villin headpiece and mutants with reduced F-actin binding activity. Biochemistry. 2005 Sep 13;44(36):11963-73. PMID:16142894 doi:10.1021/bi050850x
