| Structural highlights
Disease
[VINC_HUMAN] Defects in VCL are the cause of cardiomyopathy dilated type 1W (CMD1W) [MIM:611407]. Dilated cardiomyopathy is a disorder characterized by ventricular dilation and impaired systolic function, resulting in congestive heart failure and arrhythmia. Patients are at risk of premature death.[1] [2] Defects in VCL are the cause of familial hypertrophic cardiomyopathy type 15 (CMH15) [MIM:613255]. It is a hereditary heart disorder characterized by ventricular hypertrophy, which is usually asymmetric and often involves the interventricular septum. The symptoms include dyspnea, syncope, collapse, palpitations, and chest pain. They can be readily provoked by exercise. The disorder has inter- and intrafamilial variability ranging from benign to malignant forms with high risk of cardiac failure and sudden cardiac death.[3]
Function
[VINC_HUMAN] Actin filament (F-actin)-binding protein involved in cell-matrix adhesion and cell-cell adhesion. Regulates cell-surface E-cadherin expression and potentiates mechanosensing by the E-cadherin complex. May also play important roles in cell morphology and locomotion.[4]
Publication Abstract from PubMed
The main cause of death globally remains debilitating heart conditions, such as dilated cardiomyopathy (DCM) and hypertrophic cardiomyopathy (HCM), which are often due to mutations of specific components of adhesion complexes. Vinculin regulates these complexes and plays essential roles in intercalated discs that are necessary for muscle cell function and coordinated movement and in the development and function of the heart. Humans bearing familial or sporadic mutations in vinculin suffer from chronic, progressively debilitating DCM that ultimately leads to cardiac failure and death, whereas autosomal dominant mutations in vinculin can also provoke HCM, causing acute cardiac failure. The DCM/HCM-associated mutants of vinculin occur in the 68-residue insert unique to the muscle-specific, alternatively spliced isoform of vinculin, termed metavinculin (MV). Contrary to studies that suggested that phosphoinositol-4,5-bisphosphate (PIP2) only induces vinculin homodimers, which are asymmetric, we show that phospholipid binding results in a domain-swapped symmetric MV dimer via a quasi-equivalent interface compared with vinculin involving R975. Although one of the two PIP2 binding sites is preserved, the symmetric MV dimer that bridges two PIP2 molecules differs from the asymmetric vinculin dimer that bridges only one PIP2 Unlike vinculin, wild-type MV and the DCM/HCM-associated R975W mutant bind PIP2 in their inactive conformations, and R975W MV fails to dimerize. Mutating selective vinculin residues to their corresponding MV residues, or vice versa, switches the isoform's dimeric constellation and lipid binding site. Collectively, our data suggest that MV homodimerization modulates microfilament attachment at muscular adhesion sites and furthers our understanding of MV-mediated cardiac remodeling.
Differential lipid binding of vinculin isoforms promotes quasi-equivalent dimerization.,Chinthalapudi K, Rangarajan ES, Brown DT, Izard T Proc Natl Acad Sci U S A. 2016 Aug 23;113(34):9539-44. doi:, 10.1073/pnas.1600702113. Epub 2016 Aug 8. PMID:27503891[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Olson TM, Illenberger S, Kishimoto NY, Huttelmaier S, Keating MT, Jockusch BM. Metavinculin mutations alter actin interaction in dilated cardiomyopathy. Circulation. 2002 Jan 29;105(4):431-7. PMID:11815424
- ↑ Vasile VC, Will ML, Ommen SR, Edwards WD, Olson TM, Ackerman MJ. Identification of a metavinculin missense mutation, R975W, associated with both hypertrophic and dilated cardiomyopathy. Mol Genet Metab. 2006 Feb;87(2):169-74. Epub 2005 Oct 19. PMID:16236538 doi:S1096-7192(05)00258-1
- ↑ Vasile VC, Ommen SR, Edwards WD, Ackerman MJ. A missense mutation in a ubiquitously expressed protein, vinculin, confers susceptibility to hypertrophic cardiomyopathy. Biochem Biophys Res Commun. 2006 Jul 7;345(3):998-1003. Epub 2006 May 4. PMID:16712796 doi:S0006-291X(06)00981-8
- ↑ Le Clainche C, Dwivedi SP, Didry D, Carlier MF. Vinculin is a dually regulated actin filament barbed end-capping and side-binding protein. J Biol Chem. 2010 Jul 23;285(30):23420-32. doi: 10.1074/jbc.M110.102830. Epub, 2010 May 18. PMID:20484056 doi:10.1074/jbc.M110.102830
- ↑ Chinthalapudi K, Rangarajan ES, Brown DT, Izard T. Differential lipid binding of vinculin isoforms promotes quasi-equivalent dimerization. Proc Natl Acad Sci U S A. 2016 Aug 23;113(34):9539-44. doi:, 10.1073/pnas.1600702113. Epub 2016 Aug 8. PMID:27503891 doi:http://dx.doi.org/10.1073/pnas.1600702113
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