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De León TS, Salum ML, Matsushita Y, Fukushima K, Monge ME, Erra-Balsells R. ESI-MS reveals preferential complex formation of carbohydrates with Z-sinapinic acid compared with the E-isomer. NEW J CHEM 2022. [DOI: 10.1039/d2nj02789e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
ZSA + carbohydrate complex preferential formation and higher stability (ESI) support the previously proposed model for ZSA differential efficiency as the MALDI-MS matrix.
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Affiliation(s)
- Tobías Schmidt De León
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Orgánica, Pabellón II, 3er P., Ciudad Universitaria, 1428 Buenos Aires, Argentina
- CONICET, Universidad de Buenos Aires, Centro de Investigación en Hidratos de Carbono (CIHIDECAR), Facultad de Ciencias Exactas y Naturales Pabellón II, 3er P. Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - María Laura Salum
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Orgánica, Pabellón II, 3er P., Ciudad Universitaria, 1428 Buenos Aires, Argentina
- CONICET, Universidad de Buenos Aires, Centro de Investigación en Hidratos de Carbono (CIHIDECAR), Facultad de Ciencias Exactas y Naturales Pabellón II, 3er P. Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Yasuyuki Matsushita
- Laboratory of Forest Chemistry, Department of Forest and Environmental Resources Sciences, Graduate school of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-0814, Japan
| | - Kazuhiko Fukushima
- Laboratory of Forest Chemistry, Department of Forest and Environmental Resources Sciences, Graduate school of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-0814, Japan
| | - María Eugenia Monge
- Centro de Investigaciones en Bionanociencias (CIBION), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2390, C1425FQD, Argentina
| | - Rosa Erra-Balsells
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Orgánica, Pabellón II, 3er P., Ciudad Universitaria, 1428 Buenos Aires, Argentina
- CONICET, Universidad de Buenos Aires, Centro de Investigación en Hidratos de Carbono (CIHIDECAR), Facultad de Ciencias Exactas y Naturales Pabellón II, 3er P. Ciudad Universitaria, 1428 Buenos Aires, Argentina
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Cirilo JA, Gunther LK, Yengo CM. Functional Role of Class III Myosins in Hair Cells. Front Cell Dev Biol 2021; 9:643856. [PMID: 33718386 PMCID: PMC7947357 DOI: 10.3389/fcell.2021.643856] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/01/2021] [Indexed: 11/14/2022] Open
Abstract
Cytoskeletal motors produce force and motion using the energy from ATP hydrolysis and function in a variety of mechanical roles in cells including muscle contraction, cargo transport, and cell division. Actin-based myosin motors have been shown to play crucial roles in the development and function of the stereocilia of auditory and vestibular inner ear hair cells. Hair cells can contain hundreds of stereocilia, which rely on myosin motors to elongate, organize, and stabilize their structure. Mutations in many stereocilia-associated myosins have been shown to cause hearing loss in both humans and animal models suggesting that each myosin isoform has a specific function in these unique parallel actin bundle-based protrusions. Here we review what is known about the classes of myosins that function in the stereocilia, with a special focus on class III myosins that harbor point mutations associated with delayed onset hearing loss. Much has been learned about the role of the two class III myosin isoforms, MYO3A and MYO3B, in maintaining the precise stereocilia lengths required for normal hearing. We propose a model for how class III myosins play a key role in regulating stereocilia lengths and demonstrate how their motor and regulatory properties are particularly well suited for this function. We conclude that ongoing studies on class III myosins and other stereocilia-associated myosins are extremely important and may lead to novel therapeutic strategies for the treatment of hearing loss due to stereocilia degeneration.
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Affiliation(s)
- Joseph A Cirilo
- Department of Cellular and Molecular Physiology, College of Medicine, Pennsylvania State University, Hershey, PA, United States
| | - Laura K Gunther
- Department of Cellular and Molecular Physiology, College of Medicine, Pennsylvania State University, Hershey, PA, United States
| | - Christopher M Yengo
- Department of Cellular and Molecular Physiology, College of Medicine, Pennsylvania State University, Hershey, PA, United States
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Garcia AF, Dyszy F, Munte CE, DeMarco R, Beltramini LM, Oliva G, Costa-Filho AJ, Araujo AP. THI1, a protein involved in the biosynthesis of thiamin in Arabidopsis thaliana: Structural analysis of THI1(A140V) mutant. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1844:1094-103. [DOI: 10.1016/j.bbapap.2014.03.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 02/28/2014] [Accepted: 03/07/2014] [Indexed: 01/21/2023]
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Ma L, Wang Z, Liu S, Song F, Liu Z, Liu S. Screening calmodulin-binding ligands using intensity-fading matrix-assisted laser desorption/ionization mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2013; 27:1527-1534. [PMID: 23722687 DOI: 10.1002/rcm.6594] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 04/07/2013] [Accepted: 04/07/2013] [Indexed: 06/02/2023]
Abstract
RATIONALE Calmodulin (CaM) plays an important role in the regulation of metabolism, cytoskeleton and cell proliferation. CaM antagonists are a class of drugs that can bind to CaM and modulate the interactions between CaM and their target biological processes. Screening new calmodulin antagonists and developing novel methods for detecting calmodulin ligands are important for developing novel anti-cancer drugs that bind specifically to CaM. METHODS An intensity-fading matrix-assisted laser desorption/ionization mass spectrometry (IF-MALDI-MS) method for screening calmodulin ligands was established, with the non-binding drug propranolol as the internal control. The experimental sample was prepared by mixing the positive ligand trifluoperazine (or chlorpromazine), propranolol and Ca(2+)-CaM. The control sample was treated in the same way without the addition of CaM. The experimental and control samples were both analyzed by MALDI-MS. Based on the relative intensity fading (IF) of the ligand to propranolol, the MS conditions were optimized and then used to study the binding of eight alkaloids and calmodulin. Competitive experiments were performed in a similar way by adding two drugs to compare their binding affinities with calmodulin. RESULTS The matrix 2,6-dihydroxyacetophenone (DHAP) was suitable for detecting calmodulin ligands. Compared with propranolol, the relative intensities of six free drugs (berbamine, tetrandrine, papaverine, reserpine, brucine and tetrahydropalmatine) clearly faded after the addition of calmodulin, indicating that they can bind with CaM. The other two alkaloids (strychnine and piperine) had no or weak interaction with the target protein. Based on the data from the competitive binding experiments, the binding affinities of five drugs to calmodulin were obtained in the order: tetrandrine > trifluoperazine > berbamine > chlorpromazine > imipramine. CONCLUSIONS The IF-MALDI-MS method was successfully applied to screen novel calmodulin agents at both qualitative and semiquantitative levels. The new ligands may be novel leads for CaM antagonists.
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Affiliation(s)
- Lei Ma
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun Center of Mass Spectrometry, Changchun, PR China
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5
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Nucleotide-dependent shape changes in the reverse direction motor, myosin VI. Biophys J 2011; 99:3336-44. [PMID: 21081082 DOI: 10.1016/j.bpj.2010.09.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Revised: 08/26/2010] [Accepted: 09/09/2010] [Indexed: 11/22/2022] Open
Abstract
We have studied the shape of myosin VI, the actin minus-end directed motor, by negative stain and metal shadow electron microscopy. Single particle processing was used to make two-dimensional averages of the stain images, which greatly increases the clarity and allows detailed comparisons with crystal structures. A total of 169,964 particle images were obtained from two different constructs in six different states (four nucleotide states and with and without Ca(2+)). The shape of truncated apo myosin VI was very similar to the apo crystal structure, with the lever arm bent strongly backward and around the motor domain. In the full-length molecule, the C-terminal part of the tail has an additional bend taking it back across the motor domain, which may reflect a regulated state. Addition of ATP, ADP, or ATP-γS resulted in a large change, straightening the molecule from the bent shape and swinging the lever by ∼140°. Although these nucleotides would not be expected to produce the pre-powerstroke state, myosin VI in their presence was most similar to the truncated crystal structure with bound ADP-VO(4), which is thought to show the pre-powerstroke shape. The nucleotide data were therefore substantially different from expectation based on crystal structures. The full-length molecule was almost completely monomeric; only ∼1% were dimers, joined through the ends of the tail. Addition of calcium ions appeared to result in release of the second calmodulin light chain. In negatively stained molecules there was little indication of extended α-helical structure in the tail, but molecules viewed by metal shadowing had a tail ∼3× longer, 29 vs. 9 nm, part of which is likely to be a single α-helix.
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Erba EB, Zenobi R. Mass spectrometric studies of dissociation constants of noncovalent complexes. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1pc90006d] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Ashcroft AE. Mass spectrometry and the amyloid problem--how far can we go in the gas phase? JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:1087-1096. [PMID: 20363648 DOI: 10.1016/j.jasms.2010.02.026] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Revised: 02/16/2010] [Accepted: 02/19/2010] [Indexed: 05/29/2023]
Abstract
A number of proteins are capable of converting from their soluble, monomeric form into highly-ordered, insoluble aggregates known as amyloid fibrils. In vivo, these fibrils, which accumulate in organs and tissues, are associated with a wide range of amyloid diseases for which there are currently no therapeutic solutions. The molecular details of the pathway from native monomer through oligomeric intermediates to the final amyloid fibril remain a challenging enigma. Over the past few years, mass spectrometry has been applied to investigate the various stages of amyloid fibril formation, and this report summarizes the key steps achieved to date.
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Affiliation(s)
- Alison E Ashcroft
- Astbury Centre for Structural Molecular Biology, Institute of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom.
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Myosin VI undergoes a 180 degrees power stroke implying an uncoupling of the front lever arm. Proc Natl Acad Sci U S A 2009; 106:18255-60. [PMID: 19828438 DOI: 10.1073/pnas.0900005106] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We simultaneously measure both the step size, via FIONA, and the 3-D orientation, via DOPI, of the light-chain domain of individual dimeric myosin VIs. This allows for the correlation of the change in orientation of the light chain domain to the stepping of the motor. Three different pairs of positions were tested using a rigid bifunctional rhodamine on the calmodulin of the IQ domain. The data for all three labeling positions support the model that the light chain domain undergoes a significant rotation of approximately 180 degrees . Contrary to an earlier study [Sun, Y. et al. (2007) Mol Cell 28, 954-964], our data does not support a model of multiple angles of the lever arm of the lead head, nor "wiggly" walking on actin. Instead, we propose that for the two heads of myosin VI to coordinate their processive movement, the lever arm of the lead head must be uncoupled from the converter until the rear head detaches. More specifically, intramolecular strain causes the myosin VI lever arm of the lead head to uncouple from the motor domain, allowing the motor domain to go through its product-release (phosphate and ADP) steps at an unstrained rate. The lever arm of the lead head rebinds to the motor and attains a rigor conformation when the rear head detaches. By coupling the orientation and position information with previously described kinetics, this allows us to explain how myosin VI coordinates its heads processively while maintaining the ability to move under load with a (semi-) rigid lever arm.
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Wang Z, Yu X, Cui M, Liu Z, Song F, Liu S. Investigation of calmodulin-Peptide interactions using matrix-assisted laser desorption/ionization mass spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2009; 20:576-583. [PMID: 19110443 DOI: 10.1016/j.jasms.2008.11.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2008] [Revised: 11/20/2008] [Accepted: 11/20/2008] [Indexed: 05/27/2023]
Abstract
In this report, matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was used to study the binding interactions between calmodulin and two target peptides (melittin and substance P). Various matrix conditions were tested and the less acidic matrix DHAP and THAP were found to favor the survival of the intact calcium-calmodulin as well as the calmodulin-peptide complexes. However, the application of direct MALDI-MS to detect the intact complexes turned out to be very difficult due to the dissociation of the complexes and the formation of nonspecific aggregates. In contrast, the specific binding of the target peptides to calmodulin could be easily deduced using intensity-fading (IF) MALDI-MS. Compared with the nonbinding control, clear reduction in the ion abundances of the target peptides was observed with the addition of calmodulin. Relative binding affinities of different peptides towards the protein could also be estimated using IF-MALDI-MS. This study may extend the application of IF-MALDI-MS in the analysis of noncovalent complexes and offer a perspective into the utility of MALDI-MS as an alternative approach to study the peptides binding to calmodulin.
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Affiliation(s)
- Zhaofu Wang
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun Center of Mass Spectrometry, Changchun, PR China
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Liu J, Wang X, Cai Z, Lee FSC. Effect of tanshinone IIA on the noncovalent interaction between warfarin and human serum albumin studied by electrospray ionization mass spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2008; 19:1568-1575. [PMID: 18657993 DOI: 10.1016/j.jasms.2008.06.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2008] [Revised: 06/05/2008] [Accepted: 06/06/2008] [Indexed: 05/26/2023]
Abstract
Enhanced anticoagulation and/or even bleeding are often observed when patients on long-term warfarin (WAR) therapy consumed Danshen, a well-known medicinal herb in traditional Chinese medicine (TCM). This study demonstrates that altered WAR metabolism, arising from its interaction with the active components in Danshen, played a significant role in this curative effect. Mass spectrometric techniques including ESI-ITMS (electrospray ionization ion-trap mass spectrometry) and ESI-TOF (time-of-flight)-MS have been developed for the study of such drug-herb interactions. The experimental approach involved a detailed analysis and comparison of WAR metabolites in vivo from blood or urine of rats that had been orally administrated with WAR, either singly or together with the representative bioactive component of Danshen-lipid soluble TIIA (Tanshinon IIA), and a study of the interaction of human serum albumin (HSA), WAR, and water-soluble sodium tanshinone IIA sulfonate (STS) in vitro. Results demonstrate that TIIA accelerates the metabolic rate of WAR, whereas STS displaces WAR from the WAR-HSA complex, resulting in an increase of free WAR concentration in blood. It is suggested that the elevated level and enhanced metabolism of WAR is responsible for the over-anticoagulation effect observed.
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Affiliation(s)
- Jie Liu
- Department of Chemistry and The Key Laboratory of Analytical Science of MOE, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China
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11
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Fryčák P, Schug KA. Dynamic Titration: Determination of Dissociation Constants for Noncovalent Complexes in Multiplexed Format Using HPLC-ESI-MS. Anal Chem 2008; 80:1385-93. [DOI: 10.1021/ac7024078] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Petr Fryčák
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, 700 Planetarium Place, Arlington, Texas 76019-0065
| | - Kevin A. Schug
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, 700 Planetarium Place, Arlington, Texas 76019-0065
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12
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Abstract
Molecular motors, which use energy from ATP hydrolysis to take nanometer-scale steps with run-lengths on the order of micrometers, have important roles in areas such as transport and mitosis in living organisms. New techniques have recently been developed to measure these small movements at the single-molecule level. In particular, fluorescence imaging has contributed to the accurate measurement of this tiny movement. We introduce three single-molecule fluorescence imaging techniques which can find the position of a fluorophore with accuracy in the range of a few nanometers. These techniques are named after Hollywood animation characters: Fluorescence Imaging with One Nanometer Accuracy (FIONA), Single-molecule High-REsolution Colocalization (SHREC), and Defocused Orientation and Position Imaging (DOPI). We explain new understanding of molecular motors obtained from measurements using these techniques.
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Affiliation(s)
- Hyokeun Park
- Department of Chemistry, University of Illinois, Urbana, IL, USA
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13
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Frycák P, Schug KA. On-line dynamic titration: determination of dissociation constants for noncovalent complexes using Gaussian concentration profiles by electrospray ionization mass spectrometry. Anal Chem 2007; 79:5407-13. [PMID: 17542559 DOI: 10.1021/ac070519e] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new method for determination of dissociation constants (Kd) using on-line titration by electrospray ionization mass spectrometry is presented. Unlike in common titration experiments, where a set of discrete solutions with a fixed concentration of host and increasing concentration of guest is measured, here a continuous Gaussian concentration profile of guest, formed by band-broadening dispersion during passage through a long tubing, is utilized. An equation allowing access to dissociation constant values from experimental data fit to a 1:1 binding model was derived and incorporated into an in-house-written computer program for automated data processing. The new method is demonstrated for noncovalent complexes of cinchona alkaloid carbamate chiral selectors with N-dinitrobenzoylleucine enantiomers and a series of cyclodextrins with sulfonated azo dyes.
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Affiliation(s)
- Petr Frycák
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, 700 Planetarium Place, Arlington, Texas 76019-0065, USA
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White HD, Ashcroft AE. Real-time measurement of myosin-nucleotide noncovalent complexes by electrospray ionization mass spectrometry. Biophys J 2007; 93:914-9. [PMID: 17483158 PMCID: PMC1913167 DOI: 10.1529/biophysj.106.101618] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Nanoelectrospray ionization mass spectrometry has been used to measure the binding of ATP and ADP to the active site of rabbit skeletal myosin-S1. Increases in the molecular mass of myosin-S1 of 425 +/- 10 Da were obtained with the binding of ADP to the active site and by 530 +/- 10 Da with either ATP or hydrolysis products ADP and phosphate. Active site titrations of myosin-S1 with ADP gave a stoichiometry of approximately 1 ADP/S1 with an affinity in the micromolar range. The binding of ATP to myosin-S1 could be observed in the presence of up to 60 muM of excess MgATP without nonspecific binding of MgATP to the myosin. Conversion of the nucleotide complex containing an equilibrium mixture of ATP and ADP-Pi bound to myosin-S1 to one containing only bound ADP occurs at a rate consistent with that of the known steady-state rate of ATP hydrolysis. We expect this method to be of considerable use in the analysis of ligand binding and hydrolysis by the active sites of expressed myosin and myosin subfragments, which are not available in sufficient quantities for conventional methods of measurement of ligand binding.
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Affiliation(s)
- Howard D White
- Department of Physiological Sciences, Eastern Virginia Medical School, Norfolk, Virginia 23507, USA.
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Bryant Z, Altman D, Spudich JA. The power stroke of myosin VI and the basis of reverse directionality. Proc Natl Acad Sci U S A 2006; 104:772-7. [PMID: 17182734 PMCID: PMC1713167 DOI: 10.1073/pnas.0610144104] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Myosin VI supports movement toward the (-) end of actin filaments, despite sharing extensive sequence and structural homology with (+)-end-directed myosins. A class-specific stretch of amino acids inserted between the converter domain and the lever arm was proposed to provide the structural basis of directionality reversal. Indeed, the unique insert mediates a 120 degrees redirection of the lever arm in a crystal structure of the presumed poststroke conformation of myosin VI [Ménétrey J, Bahloul A, Wells AL, Yengo CM, Morris CA, Sweeney HL, Houdusse A (2005) Nature 435:779-785]. However, this redirection alone is insufficient to account for the large (-)-end-directed stroke of a monomeric myosin VI construct. The underlying motion of the myosin VI converter domain must therefore differ substantially from the power stroke of (+)-end-directed myosins. To experimentally map out the motion of the converter domain and lever arm, we have generated a series of truncated myosin VI constructs and characterized the size and direction of the power stroke for each construct using dual-labeled gliding filament assays and optical trapping. Motors truncated near the end of the converter domain generate (+)-end-directed motion, whereas longer constructs move toward the (-) end. Our results directly demonstrate that the unique insert is required for directionality reversal, ruling out a large class of models in which the converter domain moves toward the (-) end. We suggest that the lever arm rotates approximately 180 degrees between pre- and poststroke conformations.
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Affiliation(s)
- Zev Bryant
- *Department of Biochemistry, Stanford University School of Medicine, and
| | - David Altman
- Department of Physics, Stanford University, Stanford, CA 94305-5307
| | - James A. Spudich
- *Department of Biochemistry, Stanford University School of Medicine, and
- To whom correspondence should be addressed. E-mail:
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