The calponin regulatory region is intrinsically unstructured: novel insight into actin-calponin and calmodulin-calponin interfaces using NMR spectroscopy.
The calponin regulatory region is intrinsically unstructured: novel insight into actin-calponin and calmodulin-calponin interfaces using NMR spectroscopy.
The calponin regulatory region is intrinsically unstructured: novel insight into actin-calponin and calmodulin-calponin interfaces using NMR spectroscopy.
Biophys J. 2011 Apr 6;100(7):1718-28
Authors: Pfuhl M, Al-Sarayreh S, El-Mezgueldi M
Calponin is an actin- and calmodulin-binding protein believed to regulate the function of actin. Low-resolution studies based on proteolysis established that the recombinant calponin fragment 131-228 contained actin and calmodulin recognition sites but failed to precisely identify the actin-binding determinants. In this study, we used NMR spectroscopy to investigate the structure of this functionally important region of calponin and map its interaction with actin and calmodulin at amino-acid resolution. Our data indicates that the free calponin peptide is largely unstructured in solution, although four short amino-acid stretches corresponding to residues 140-146, 159-165, 189-195, and 199-205 display the propensity to form ?-helices. The presence of four sequential transient helices probably provides the conformational malleability needed for the promiscuous nature of this region of calponin. We identified all amino acids involved in actin binding and demonstrated for the first time, to our knowledge, that the N-terminal flanking region of Lys(137)-Tyr(144) is an integral part of the actin-binding site. We have also delineated the second actin-binding site to amino acids Thr(180)-Asp(190). Ca(2+)-calmodulin binding extends beyond the previously identified minimal sequence of 153-163 and includes most amino acids within the stretch 143-165. In addition, we found that calmodulin induces chemical shift perturbations of amino acids 188-190 demonstrating for the first time, to our knowledge, an effect of Ca(2+)-calmodulin on this region. The spatial relationship of the actin and calmodulin contacts as well as the transient ?-helical structures within the regulatory region of calponin provides a structural framework for understanding the Ca(2+)-dependent regulation of the actin-calponin interaction by calmodulin.
Covalent structural changes in unfolded GroES that lead to amyloid fibril formation detected by NMR: Insight into intrinsically disordered proteins.
Covalent structural changes in unfolded GroES that lead to amyloid fibril formation detected by NMR: Insight into intrinsically disordered proteins.
Covalent structural changes in unfolded GroES that lead to amyloid fibril formation detected by NMR: Insight into intrinsically disordered proteins.
J Biol Chem. 2011 Apr 20;
Authors: Iwasa H, Meshitsuka S, Hongo K, Mizobata T, Kawata Y
Co-chaperonin GroES from E. coli works with chaperonin GroEL to mediate the folding reactions of various proteins. However, under specific conditions, i. e., the...
[NMR paper] NMR relaxation studies on the hydrate layer of intrinsically unstructured proteins.
NMR relaxation studies on the hydrate layer of intrinsically unstructured proteins.
Related Articles NMR relaxation studies on the hydrate layer of intrinsically unstructured proteins.
Biophys J. 2005 Mar;88(3):2030-7
Authors: Bokor M, Csizmók V, Kovács D, Bánki P, Friedrich P, Tompa P, Tompa K
Intrinsically unstructured/disordered proteins (IUPs) exist in a disordered and largely solvent-exposed, still functional, structural state under physiological conditions. As their function is often directly linked with structural disorder,...
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[NMR paper] Fast mapping of protein-protein interfaces by NMR spectroscopy.
Fast mapping of protein-protein interfaces by NMR spectroscopy.
Related Articles Fast mapping of protein-protein interfaces by NMR spectroscopy.
J Am Chem Soc. 2003 Nov 26;125(47):14250-1
Authors: Reese ML, Dötsch V
Identifying the interface of protein complexes can represent a difficult task in structural biology. Here, we report a method for the fast mapping of interfaces of protein complexes by NMR without the need for the assignments of the proteins involved.
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[NMR paper] Calcium-induced refolding of the calmodulin V136G mutant studied by NMR spectroscopy:
Calcium-induced refolding of the calmodulin V136G mutant studied by NMR spectroscopy: evidence for interaction between the two globular domains.
Related Articles Calcium-induced refolding of the calmodulin V136G mutant studied by NMR spectroscopy: evidence for interaction between the two globular domains.
Biochemistry. 2000 Dec 26;39(51):15920-31
Authors: Fefeu S, Biekofsky RR, McCormick JE, Martin SR, Bayley PM, Feeney J
The Ca(2+) titration of the (15)N-labeled mutant V136G calmodulin has been monitored using (1)H-(15)N HSQC NMR spectra. Up...
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[NMR paper] Characterization of trimethyllysine 115 in calmodulin by 14N and 13C NMR spectroscopy
Characterization of trimethyllysine 115 in calmodulin by 14N and 13C NMR spectroscopy.
Related Articles Characterization of trimethyllysine 115 in calmodulin by 14N and 13C NMR spectroscopy.
J Biol Chem. 1994 Feb 18;269(7):5099-105
Authors: Zhang M, Huque E, Vogel HJ
In this paper, we describe three approaches to study the single trimethyllysine 115 in calmodulin. First, 14N NMR spectroscopy has been used as a novel spectroscopic tool. Because of the unique symmetrical tetrahedral substitution of its side chain, the trimethyllysine residue...
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[NMR paper] Characterization of trimethyllysine 115 in calmodulin by 14N and 13C NMR spectroscopy
Characterization of trimethyllysine 115 in calmodulin by 14N and 13C NMR spectroscopy.
Related Articles Characterization of trimethyllysine 115 in calmodulin by 14N and 13C NMR spectroscopy.
J Biol Chem. 1994 Feb 18;269(7):5099-105
Authors: Zhang M, Huque E, Vogel HJ
In this paper, we describe three approaches to study the single trimethyllysine 115 in calmodulin. First, 14N NMR spectroscopy has been used as a novel spectroscopic tool. Because of the unique symmetrical tetrahedral substitution of its side chain, the trimethyllysine residue...
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NMR structure of the calponin homology domain of human IQGAP1 and its implications fo
NMR structure of the calponin homology domain of human IQGAP1 and its implications for the actin recognition mode
Content Type Journal Article
DOI 10.1007/s10858-010-9434-8
Authors
Ryo Umemoto, The University of Tokyo Graduate School of Pharmaceutical Sciences Hongo, Bunkyo-ku Tokyo 113-0033 Japan
Noritaka Nishida, The University of Tokyo Graduate School of Pharmaceutical Sciences Hongo, Bunkyo-ku Tokyo 113-0033 Japan
Shinji Ogino, The University of Tokyo Graduate School of Pharmaceutical Sciences Hongo, Bunkyo-ku Tokyo 113-0033 Japan
The calponin regulatory region is intrinsically unstructured: novel insight into actin-calponin and calmodulin-calponin interfaces using NMR spectroscopy.
Linear Mode
