» Articles » PMID: 19134474

Induced Secondary Structure and Polymorphism in an Intrinsically Disordered Structural Linker of the CNS: Solid-state NMR and FTIR Spectroscopy of Myelin Basic Protein Bound to Actin

Overview
Journal Biophys J
Publisher Cell Press
Specialty Biophysics
Date 2009 Jan 13
PMID 19134474
Citations 10
Authors
Affiliations
Soon will be listed here.
Abstract

The 18.5 kDa isoform of myelin basic protein (MBP) is a peripheral membrane protein that maintains the structural integrity of the myelin sheath of the central nervous system by conjoining the cytoplasmic leaflets of oligodendrocytes and by linking the myelin membrane to the underlying cytoskeleton whose assembly it strongly promotes. It is a multifunctional, intrinsically disordered protein that behaves primarily as a structural stabilizer, but with elements of a transient or induced secondary structure that represent binding sites for calmodulin or SH3-domain-containing proteins, inter alia. In this study we used solid-state NMR (SSNMR) and Fourier transform infrared (FTIR) spectroscopy to study the conformation of 18.5 kDa MBP in association with actin microfilaments and bundles. FTIR spectroscopy of fully (13)C,(15)N-labeled MBP complexed with unlabeled F-actin showed induced folding of both protein partners, viz., some increase in beta-sheet content in actin, and increases in both alpha-helix and beta-sheet content in MBP, albeit with considerable extended structure remaining. Solid-state NMR spectroscopy revealed that MBP in MBP-actin assemblies is structurally heterogeneous but gains ordered secondary structure elements (both alpha-helical and beta-sheet), particularly in the terminal fragments and in a central immunodominant epitope. The overall conformational polymorphism of MBP is consistent with its in vivo roles as both a linker (membranes and cytoskeleton) and a putative signaling hub.

Citing Articles

Structural Analysis of Human Cofilin 2/Filamentous Actin Assemblies: Atomic-Resolution Insights from Magic Angle Spinning NMR Spectroscopy.

Yehl J, Kudryashova E, Reisler E, Kudryashov D, Polenova T Sci Rep. 2017; 7:44506.

PMID: 28303963 PMC: 5355874. DOI: 10.1038/srep44506.


Proton detection for signal enhancement in solid-state NMR experiments on mobile species in membrane proteins.

Ward M, Ritz E, Ahmed M, Bamm V, Harauz G, Brown L J Biomol NMR. 2015; 63(4):375-388.

PMID: 26494649 DOI: 10.1007/s10858-015-9997-5.


The proline-rich region of 18.5 kDa myelin basic protein binds to the SH3-domain of Fyn tyrosine kinase with the aid of an upstream segment to form a dynamic complex in vitro.

De Avila M, Vassall K, Smith G, Bamm V, Harauz G Biosci Rep. 2014; 34(6):e00157.

PMID: 25343306 PMC: 4266924. DOI: 10.1042/BSR20140149.


Glatiramer acetate and nanny proteins restrict access of the multiple sclerosis autoantigen myelin basic protein to the 26S proteasome.

Kuzina E, Kudriaeva A, Smirnov I, Dubina M, Gabibov A, Belogurov Jr A Biomed Res Int. 2014; 2014:926394.

PMID: 25276831 PMC: 4172982. DOI: 10.1155/2014/926394.


Myelin management by the 18.5-kDa and 21.5-kDa classic myelin basic protein isoforms.

Harauz G, Boggs J J Neurochem. 2013; 125(3):334-61.

PMID: 23398367 PMC: 3700880. DOI: 10.1111/jnc.12195.


References
1.
Dobrowolski Z, Osinska H, Mossakowska M, Barylko B . Ca2+-calmodulin-dependent polymerization of actin by myelin basic protein. Eur J Cell Biol. 1986; 42(1):17-26. View

2.
Thompson L . Solid-state NMR studies of the structure and mechanisms of proteins. Curr Opin Struct Biol. 2002; 12(5):661-9. DOI: 10.1016/s0959-440x(02)00374-3. View

3.
Baumann N, Pham-Dinh D . Biology of oligodendrocyte and myelin in the mammalian central nervous system. Physiol Rev. 2001; 81(2):871-927. DOI: 10.1152/physrev.2001.81.2.871. View

4.
Hardy E, Verel R, Meier B . Fast MAS total through-bond correlation spectroscopy. J Magn Reson. 2001; 148(2):459-64. DOI: 10.1006/jmre.2000.2258. View

5.
Polverini E, Rangaraj G, Libich D, Boggs J, Harauz G . Binding of the proline-rich segment of myelin basic protein to SH3 domains: spectroscopic, microarray, and modeling studies of ligand conformation and effects of posttranslational modifications. Biochemistry. 2007; 47(1):267-82. DOI: 10.1021/bi701336n. View