Structural analysis of the complex between calmodulin and full-length myelin basic protein, an intrinsically disordered molecule

The classic 18.5 kDa isoform of myelin basic protein (MBP) is central to maintaining the structural homeostasis of the myelin sheath of the central nervous system. It is an intrinsically disordered, promiscuous, multifunctional, peripheral membrane protein, whose conformation adapts to its particular environment. Its study requires the selective and complementary application of diverse approaches, of which solution and solid-state NMR spectroscopy are the most powerful to elucidate site-specific features. We review here several recent solution and solid-state NMR spectroscopic studies of 18.5 kDa MBP, and the induced partial disorder-to-order transitions that it has been demonstrated to undergo when complexed with calmodulin, actin, and phospholipid membranes.

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MyelStones: the executive roles of myelin basic protein in myelin assembly and destabilization in multiple sclerosis

Biochemical Journal ◽

10.1042/bj20150710 ◽

2015 ◽

Vol 472 (1) ◽

pp. 17-32 ◽

Cited By ~ 44

Author(s):

Kenrick A. Vassall ◽

Vladimir V. Bamm ◽

George Harauz

Keyword(s):

Multiple Sclerosis ◽

Myelin Basic Protein ◽

Intrinsically Disordered Proteins ◽

Basic Protein ◽

Disordered Proteins ◽

Post Translational Modifications ◽

Src Homology 3 ◽

Intrinsically Disordered ◽

Src Homology ◽

Membrane Anchoring

The classic isoforms of myelin basic protein (MBP, 14–21.5 kDa) are essential to formation of the multilamellar myelin sheath of the mammalian central nervous system (CNS). The predominant 18.5-kDa isoform links together the cytosolic surfaces of oligodendrocytes, but additionally participates in cytoskeletal turnover and membrane extension, Fyn-mediated signalling pathways, sequestration of phosphoinositides and maintenance of calcium homoeostasis. All MBP isoforms are intrinsically disordered proteins (IDPs) that interact via molecular recognition fragments (MoRFs), which thereby undergo local disorder-to-order transitions. Their conformations and associations are modulated by environment and by a dynamic barcode of post-translational modifications, particularly phosphorylation by mitogen-activated and other protein kinases and deimination [a hallmark of demyelination in multiple sclerosis (MS)]. The MBPs are thus to myelin what basic histones are to chromatin. Originally thought to be merely structural proteins forming an inert spool, histones are now known to be dynamic entities involved in epigenetic regulation and diseases such as cancer. Analogously, the MBPs are not mere adhesives of compact myelin, but active participants in oligodendrocyte proliferation and in membrane process extension and stabilization during myelinogenesis. A central segment of these proteins is pivotal in membrane-anchoring and SH3 domain (Src homology 3) interaction. We discuss in the present review advances in our understanding of conformational conversions of this classic basic protein upon membrane association, including new thermodynamic analyses of transitions into different structural ensembles and how a shift in the pattern of its post-translational modifications is associated with the pathogenesis and potentially onset of demyelination in MS.

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Solution NMR and CD spectroscopy of an intrinsically disordered, peripheral membrane protein: evaluation of aqueous and membrane-mimetic solvent conditions for studying the conformational adaptability of the 18.5 kDa isoform of myelin basic protein (MBP)

European Biophysics Journal ◽

10.1007/s00249-008-0334-8 ◽

2008 ◽

Vol 37 (6) ◽

pp. 1015-1029 ◽

Cited By ~ 26

Author(s):

David S. Libich ◽

George Harauz

Keyword(s):

Membrane Protein ◽

Myelin Basic Protein ◽

Basic Protein ◽

Cd Spectroscopy ◽

Solution Nmr ◽

Intrinsically Disordered ◽

Membrane Mimetic ◽

Peripheral Membrane Protein

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Reduced Internal Friction by Osmolyte Interaction in Intrinsically Disordered Myelin Basic Protein

The Journal of Physical Chemistry Letters ◽

10.1021/acs.jpclett.9b03001 ◽

2019 ◽

Vol 11 (1) ◽

pp. 292-296 ◽

Cited By ~ 1

Author(s):

Laura R. Stingaciu ◽

Ralf Biehl ◽

Do Changwoo ◽

Dieter Richter ◽

Andreas M. Stadler

Keyword(s):

Internal Friction ◽

Myelin Basic Protein ◽

Basic Protein ◽

Intrinsically Disordered

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NMR assignment of an intrinsically disordered protein under physiological conditions: the 18.5 kDa isoform of murine myelin basic protein

Biomolecular NMR Assignments ◽

10.1007/s12104-007-9016-1 ◽

2007 ◽

Vol 1 (1) ◽

pp. 61-63 ◽

Cited By ~ 8

Author(s):

David S. Libich ◽

Martine M. Monette ◽

Valerie J. Robertson ◽

George Harauz

Keyword(s):

Myelin Basic Protein ◽

Nmr Assignment ◽

Basic Protein ◽

Intrinsically Disordered Protein ◽

Physiological Conditions ◽

Intrinsically Disordered ◽

Disordered Protein

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Molecular characterization of myelin basic protein a (mbpa) gene from red-bellied pacu (Piaractus brachypomus)

Journal of Genetic Engineering and Biotechnology ◽

10.1186/s43141-022-00296-6 ◽

2022 ◽

Vol 20 (1) ◽

Author(s):

Juan Sebastian Cruz-Méndez ◽

María Paula Herrera-Sánchez ◽

Ángel Enrique Céspedes-Rubio ◽

Iang Schroniltgen Rondón-Barragán

Keyword(s):

Gene Expression ◽

Brain Injury ◽

Myelin Basic Protein ◽

Molecular Characterization ◽

Basic Protein ◽

Protein A ◽

Intrinsically Disordered ◽

Intrinsically Disordered Regions ◽

Disordered Regions

Abstract Background Myelin basic protein (MBP) is one of the most important structural components of the myelin sheaths in both central and peripheral nervous systems. MBP has several functions including organization of the myelin membranes, reorganization of the cytoskeleton during the myelination process, and interaction with the SH3 domain in signaling pathways. Likewise, MBP has been proposed as a marker of demyelination in traumatic brain injury and chemical exposure. Methods The aim of this study was to molecularly characterize the myelin basic protein a (mbpa) gene from the Colombian native fish, red-bellied pacu, Piaractus brachypomus. Bioinformatic tools were used to identify the phylogenetic relationships, physicochemical characteristics, exons, intrinsically disordered regions, and conserved domains of the protein. Gene expression was assessed by qPCR in three models corresponding to sublethal chlorpyrifos exposure, acute brain injury, and anesthesia experiments. Results mbpa complete open reading frame was identified with 414 nucleotides distributed in 7 exons that encode 137 amino acids. MBPa was recognized as belonging to the myelin basic protein family, closely related with orthologous proteins, and two intrinsically disordered regions were established within the sequence. Gene expression of mbpa was upregulated in the optic chiasm of the chlorpyrifos exposed fish in contrast to the control group. Conclusions The physicochemical computed features agree with the biological functions of MBP, and basal gene expression was according to the anatomical distribution in the tissues analyzed. This study is the first molecular characterization of mbpa from the native species Piaractus brachypomus.

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Saccharomyces cerevisiae Yak1p protein kinase autophosphorylates on tyrosine residues and phosphorylates myelin basic protein on a C-terminal serine residue

Biochemical Journal ◽

10.1042/bj3480263 ◽

2000 ◽

Vol 348 (2) ◽

pp. 263-272 ◽

Cited By ~ 17

Author(s):

Shouki KASSIS ◽

Tiffany MELHUISH ◽

Roland S. ANNAN ◽

Susan L. CHEN ◽

John C. LEE ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Catalytic Activity ◽

Protein Kinase ◽

Myelin Basic Protein ◽

Basic Protein ◽

Full Length ◽

Tandem Ms ◽

Tyrosine Residues

The serine/threonine protein kinase, Yak1p, functions as a negative regulator of the cell cycle in Saccharomyces cerevisiae, acting downstream of the cAMP-dependent protein kinase. In the present work we report that overexpression of haemagglutinin-tagged full-lengthYak1p and an N-terminally truncated form (residues 148-807) lead to growth arrest in PKA compromised yak1 null yeast cells. Both forms of recombinant Yak1p kinase were catalytically active and preferred myelin basic protein (MBP) as a substrate over several other proteins. Phosphopeptide analysis of bovine MBP by tandem MS revealed two major Yak1p phosphorylation sites, Thr-97 and Ser-164. Peptides containing each site were obtained and tested as Yak1p substrates. Both forms of Yak1p phosphorylated a peptide containing the Ser-164 residue with far more efficient kinetics than MBP. The maximal velocity (Vmax) values of the full-length Yak1p reaction were 110±21 (Ser-164) and 8.7±1.7 (MBP), and those of N-terminally truncated Yak1p were 560.7±74.8 (Ser-164) and 34.4±2.2 (MBP) pmol/min per mg of protein. Although neither form of Yak1p was able to phosphorylate two generic protein tyrosine kinase substrates, both were phosphorylated on tyrosine residues in vivo and underwent tyrosine autophosphorylation when reacted with ATP in vitro. Tandem MS showed that Tyr-530 was phosphorylated both in vivo and in vitro after reaction with ATP. Pre-treatment with protein tyrosine phosphatase 1B removed all of Yak1p phosphotyrosine content and drastically reduced Yak1p activity against exogenous substrates, suggesting that the phosphotyrosine content of the enzyme is essential for its catalytic activity. Although the N-terminally truncated Yak1p was expressed at a lower level than the full-length protein, its catalytic activity and phosphotyrosine content were significantly higher than those of the full-length enzyme. Taken together, our results suggest that Yak1p is a dual specificity protein kinase which autophosphorylates on Tyr-530 and phosphorylates exogenous substrates on Ser/Thr residues.

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