Distinct Binding Modes of Vinculin Isoforms Underlie Their Functional Differences

Andrey Krokhotin; Muzaddid Sarker; Ernesto Alva Sevilla; Lindsey M Costantini; Jack D Griffith; Sharon L Campbell; Nikolay V Dokholyan

doi:10.1016/j.str.2019.07.013

Distinct Binding Modes of Vinculin Isoforms Underlie Their Functional Differences

Structure. 2019 Oct 1;27(10):1527-1536.e3. doi: 10.1016/j.str.2019.07.013. Epub 2019 Aug 15.

Authors

Andrey Krokhotin¹, Muzaddid Sarker², Ernesto Alva Sevilla³, Lindsey M Costantini⁴, Jack D Griffith⁴, Sharon L Campbell⁵, Nikolay V Dokholyan⁶

Affiliations

¹ Department of Biochemistry and Biophysics and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Departments of Pathology, Genetics and Developmental Biology, Howard Hughes Medical Institute, Stanford Medical School, Palo Alto, CA 94305, USA.
² Department of Biochemistry and Biophysics and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada.
³ Department of Biochemistry and Biophysics and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
⁴ Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
⁵ Department of Biochemistry and Biophysics and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. Electronic address: campbesl@med.unc.edu.
⁶ Department of Biochemistry and Biophysics and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Departments of Pharmacology and Departments of Biochemistry and Molecular Biology, Penn State College of Medicine, Hershey, PA 17033, USA. Electronic address: dokh@psu.edu.

Abstract

Vinculin and its splice isoform metavinculin play key roles in regulating cellular morphology, motility, and force transduction. Vinculin is distinct from metavinculin in its ability to bundle filamentous actin (F-actin). To elucidate the molecular basis for these differences, we employed computational and experimental approaches. Results from these analyses suggest that the C terminus of both vinculin and metavinculin form stable interactions with the F-actin surface. However, the metavinculin tail (MVt) domain contains a 68 amino acid insert, with helix 1 (H1) sequestered into a globular subdomain, which protrudes from the F-actin surface and prevents actin bundling by sterically occluding actin filaments. Consistent with our model, deletion and selective point mutations within the MVt H1 disrupt this protruding structure, and facilitate actin bundling similar to vinculin tail (Vt) domain.

Keywords: actin; cardiomyopathy; heart; metavinculin; molecular dynamics; vinculin.

Publication types

Research Support, N.I.H., Extramural

MeSH terms

Actins
Alternative Splicing
Animals
Binding Sites
Cryoelectron Microscopy
Models, Molecular
Mutation
Protein Binding
Protein Domains
Protein Structure, Secondary
Vinculin / chemistry*
Vinculin / genetics
Vinculin / metabolism*

Substances

Actins
metavinculin
Vinculin

Abstract

Publication types

MeSH terms

Substances

Grants and funding