1
|
Jia N, Zhang B, Huo Z, Qin J, Ji Q, Geng Y. Binding patterns of inhibitors to different pockets of kinesin Eg5. Arch Biochem Biophys 2024; 756:109998. [PMID: 38641233 DOI: 10.1016/j.abb.2024.109998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 03/19/2024] [Accepted: 04/12/2024] [Indexed: 04/21/2024]
Abstract
The kinesin-5 family member, Eg5, plays very important role in the mitosis. As a mitotic protein, Eg5 is the target of various mitotic inhibitors. There are two targeting pockets in the motor domain of Eg5, which locates in the α2/L5/α3 region and the α4/α6 region respectively. We investigated the interactions between the different inhibitors and the two binding pockets of Eg5 by using all-atom molecular dynamics method. Combined the conformational analysis with the free-energy calculation, the binding patterns of inhibitors to the two binding pockets are shown. The α2/L5/α3 pocket can be divided into 4 regions. The structures and binding conformations of inhibitors in region 1 and 2 are highly conserved. The shape of α4/α6 pocket is alterable. The space of this pocket in ADP-binding state of Eg5 is larger than that in ADP·Pi-binding state due to the limitation of a hydrogen bond formed in the ADP·Pi-binding state. The results of this investigation provide the structural basis of the inhibitor-Eg5 interaction and offer a reference for the Eg5-targeted drug design.
Collapse
Affiliation(s)
- Ning Jia
- School of Science, Hebei University of Technology, Tianjin, China; Institute of Biophysics, Hebei University of Technology, Tianjin, China
| | - Bingbing Zhang
- School of Health Sciences & Biomedical Engineering, Hebei University of Technology, Tianjin, China; Institute of Biophysics, Hebei University of Technology, Tianjin, China
| | - Ziling Huo
- School of Health Sciences & Biomedical Engineering, Hebei University of Technology, Tianjin, China; Institute of Biophysics, Hebei University of Technology, Tianjin, China
| | - Jingyu Qin
- College of Electrical and Information Engineering, Quzhou University, Quzhou, China
| | - Qing Ji
- School of Science, Hebei University of Technology, Tianjin, China; Institute of Biophysics, Hebei University of Technology, Tianjin, China
| | - Yizhao Geng
- School of Science, Hebei University of Technology, Tianjin, China; Institute of Biophysics, Hebei University of Technology, Tianjin, China.
| |
Collapse
|
2
|
Xie P. A Model for Chemomechanical Coupling of Kinesin-3 Motor. Cell Mol Bioeng 2024; 17:137-151. [PMID: 38737453 PMCID: PMC11082130 DOI: 10.1007/s12195-024-00795-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 01/11/2024] [Indexed: 05/14/2024] Open
Abstract
Introduction Kinesin-3 motor, which is in the monomeric and inactive form in solution, after cargo-induced dimerization can step on microtubules towards the plus end with a high velocity and a supperprocessivity, which is responsible for transporting the cargo in axons and dendrites. The kinesin-3 motor has a large initial landing rate to microtubules and spends the majority of its stepping cycle in a one-head-bound state. Under the load the kinesin-3 motor can dissociate more readily than the kinesin-1 motor. Methods To understand the physical origin of the peculiar features for the kinesin-3 motor, a model is presented here for its chemomechanical coupling. Based on the model the dynamics of the motor under no load, under the ramping load and under the constant load is studied analytically. Results The theoretical results explain well the available experimental data under no load and under the ramping load. For comparison, the corresponding available experimental data for the kinesin-1 motor under the ramping load are also explained. The predicted results of the velocity, dissociation rate and run length versus the constant load for the kinesin-3 motor are provided. Conclusions The study has strong implications for the chemomechanical coupling mechanism of the kinesin-3 dimer. The origin of the kinesin-3 dimer in the predominant one-head-bound state is due to the fact that the rate of ATP transition to ADP in the trailing head is much larger than that of ADP release from the MT-bound head. The study shows that the kinesin-3 ADP-head has an evidently longer interaction distance with microtubule than the kinesin-1 ADP-head, explaining why in the initial ADP state the kinesin-3 motor has the much larger landing rate than the kinesin-1 motor and why under the load the kinesin-3 motor can dissociate more readily than the kinesin-1 motor. Supplementary Information The online version contains supplementary material available at 10.1007/s12195-024-00795-1.
Collapse
Affiliation(s)
- Ping Xie
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Science, Beijing, 100190 China
| |
Collapse
|
3
|
Soustelle L, Aimond F, López-Andrés C, Brugioti V, Raoul C, Layalle S. ALS-Associated KIF5A Mutation Causes Locomotor Deficits Associated with Cytoplasmic Inclusions, Alterations of Neuromuscular Junctions, and Motor Neuron Loss. J Neurosci 2023; 43:8058-8072. [PMID: 37748861 PMCID: PMC10669773 DOI: 10.1523/jneurosci.0562-23.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 09/12/2023] [Accepted: 09/13/2023] [Indexed: 09/27/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting motor neurons. Recently, genome-wide association studies identified KIF5A as a new ALS-causing gene. KIF5A encodes a protein of the kinesin-1 family, allowing the anterograde transport of cargos along the microtubule rails in neurons. In ALS patients, mutations in the KIF5A gene induce exon 27 skipping, resulting in a mutated protein with a new C-terminal region (KIF5A Δ27). To understand how KIF5A Δ27 underpins the disease, we developed an ALS-associated KIF5A Drosophila model. When selectively expressed in motor neurons, KIF5A Δ27 alters larval locomotion as well as morphology and synaptic transmission at neuromuscular junctions in both males and females. We show that the distribution of mitochondria and synaptic vesicles is profoundly disturbed by KIF5A Δ27 expression. That is consistent with the numerous KIF5A Δ27-containing inclusions observed in motor neuron soma and axons. Moreover, KIF5A Δ27 expression leads to motor neuron death and reduces life expectancy. Our in vivo model reveals that a toxic gain of function underlies the pathogenicity of ALS-linked KIF5A mutant.SIGNIFICANCE STATEMENT Understanding how a mutation identified in patients with amyotrophic lateral sclerosis (ALS) causes the disease and the loss of motor neurons is crucial to fight against this disease. To this end, we have created a Drosophila model based on the motor neuron expression of the KIF5A mutant gene, recently identified in ALS patients. KIF5A encodes a kinesin that allows the anterograde transport of cargos. This model recapitulates the main features of ALS, including alterations of locomotion, synaptic neurotransmission, and morphology at neuromuscular junctions, as well as motor neuron death. KIF5A mutant is found in cytoplasmic inclusions, and its pathogenicity is because of a toxic gain of function.
Collapse
Affiliation(s)
- Laurent Soustelle
- Institute for Neurosciences Montpellier, Université Montpellier, Institut National de la Santé et de la Recherche Médicale, Montpellier, 34091, France
| | - Franck Aimond
- Institute for Neurosciences Montpellier, Université Montpellier, Institut National de la Santé et de la Recherche Médicale, Montpellier, 34091, France
| | - Cristina López-Andrés
- Institute for Neurosciences Montpellier, Université Montpellier, Institut National de la Santé et de la Recherche Médicale, Montpellier, 34091, France
| | - Véronique Brugioti
- Institute for Neurosciences Montpellier, Université Montpellier, Institut National de la Santé et de la Recherche Médicale, Montpellier, 34091, France
| | - Cédric Raoul
- Institute for Neurosciences Montpellier, Université Montpellier, Institut National de la Santé et de la Recherche Médicale, Montpellier, 34091, France
| | - Sophie Layalle
- Institute for Neurosciences Montpellier, Université Montpellier, Institut National de la Santé et de la Recherche Médicale, Montpellier, 34091, France
| |
Collapse
|
4
|
Banerjee R, Gunawardena S. Glycogen synthase kinase 3β (GSK3β) and presenilin (PS) are key regulators of kinesin-1-mediated cargo motility within axons. Front Cell Dev Biol 2023; 11:1202307. [PMID: 37363727 PMCID: PMC10288942 DOI: 10.3389/fcell.2023.1202307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Accepted: 05/25/2023] [Indexed: 06/28/2023] Open
Abstract
It has been a quarter century since the discovery that molecular motors are phosphorylated, but fundamental questions still remain as to how specific kinases contribute to particular motor functions, particularly in vivo, and to what extent these processes have been evolutionarily conserved. Such questions remain largely unanswered because there is no cohesive strategy to unravel the likely complex spatial and temporal mechanisms that control motility in vivo. Since diverse cargoes are transported simultaneously within cells and along narrow long neurons to maintain intracellular processes and cell viability, and disruptions in these processes can lead to cancer and neurodegeneration, there is a critical need to better understand how kinases regulate molecular motors. Here, we review our current understanding of how phosphorylation can control kinesin-1 motility and provide evidence for a novel regulatory mechanism that is governed by a specific kinase, glycogen synthase kinase 3β (GSK3β), and a scaffolding protein presenilin (PS).
Collapse
Affiliation(s)
- Rupkatha Banerjee
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, FL, United States
| | - Shermali Gunawardena
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY, United States
| |
Collapse
|
5
|
Wirth JO, Scheiderer L, Engelhardt T, Engelhardt J, Matthias J, Hell SW. MINFLUX dissects the unimpeded walking of kinesin-1. Science 2023; 379:1004-1010. [PMID: 36893244 DOI: 10.1126/science.ade2650] [Citation(s) in RCA: 33] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 01/23/2023] [Indexed: 03/11/2023]
Abstract
We introduce an interferometric MINFLUX microscope that records protein movements with up to 1.7 nanometer per millisecond spatiotemporal precision. Such precision has previously required attaching disproportionately large beads to the protein, but MINFLUX requires the detection of only about 20 photons from an approximately 1-nanometer-sized fluorophore. Therefore, we were able to study the stepping of the motor protein kinesin-1 on microtubules at up to physiological adenosine-5'-triphosphate (ATP) concentrations. We uncovered rotations of the stalk and the heads of load-free kinesin during stepping and showed that ATP is taken up with a single head bound to the microtubule and that ATP hydrolysis occurs when both heads are bound. Our results show that MINFLUX quantifies (sub)millisecond conformational changes of proteins with minimal disturbance.
Collapse
Affiliation(s)
- Jan O Wirth
- Department of Optical Nanoscopy, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Lukas Scheiderer
- Department of Optical Nanoscopy, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Tobias Engelhardt
- Department of Optical Nanoscopy, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Johann Engelhardt
- Department of Optical Nanoscopy, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Jessica Matthias
- Department of Optical Nanoscopy, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Stefan W Hell
- Department of Optical Nanoscopy, Max Planck Institute for Medical Research, Heidelberg, Germany
- Department of NanoBiophotonics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| |
Collapse
|
6
|
Capitanio M, Reconditi M. Editorial to the Special Issue "Molecular Motors: From Single Molecules to Cooperative and Regulatory Mechanisms In Vivo". Int J Mol Sci 2022; 23:ijms23126605. [PMID: 35743049 PMCID: PMC9223856 DOI: 10.3390/ijms23126605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 06/07/2022] [Indexed: 02/01/2023] Open
Abstract
The Molecular motors or motor proteins are able to generate force and do mechanical work that is used to displace a load or produce relative movements between molecules or macromolecular assembles [...].
Collapse
Affiliation(s)
- Marco Capitanio
- Department of Physics and Astronomy, University of Florence, 50019 Florence, Italy;
- LENS—European Laboratory for Non-Linear Spectroscopy, 50019 Florence, Italy
| | - Massimo Reconditi
- Department of Experimental and Clinical Medicine, University of Florence, 50134 Florence, Italy
- PhysioLab, University of Florence, 50019 Florence, Italy
- Correspondence:
| |
Collapse
|
7
|
Budaitis BG, Badieyan S, Yue Y, Blasius TL, Reinemann DN, Lang MJ, Cianfrocco MA, Verhey KJ. A kinesin-1 variant reveals motor-induced microtubule damage in cells. Curr Biol 2022; 32:2416-2429.e6. [PMID: 35504282 PMCID: PMC9993403 DOI: 10.1016/j.cub.2022.04.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 03/11/2022] [Accepted: 04/08/2022] [Indexed: 12/16/2022]
Abstract
Kinesins drive the transport of cellular cargoes as they walk along microtubule tracks; however, recent work has suggested that the physical act of kinesins walking along microtubules can stress the microtubule lattice. Here, we describe a kinesin-1 KIF5C mutant with an increased ability to generate damage sites in the microtubule lattice as compared with the wild-type motor. The expression of the mutant motor in cultured cells resulted in microtubule breakage and fragmentation, suggesting that kinesin-1 variants with increased damage activity would have been selected against during evolution. The increased ability to damage microtubules is not due to the enhanced motility properties of the mutant motor, as the expression of the kinesin-3 motor KIF1A, which has similar single-motor motility properties, also caused increased microtubule pausing, bending, and buckling but not breakage. In cells, motor-induced microtubule breakage could not be prevented by increased α-tubulin K40 acetylation, a post-translational modification known to increase microtubule flexibility. In vitro, lattice damage induced by wild-type KIF5C was repaired by soluble tubulin and resulted in increased rescues and overall microtubule growth, whereas lattice damage induced by the KIF5C mutant resulted in larger repair sites that made the microtubule vulnerable to breakage and fragmentation when under mechanical stress. These results demonstrate that kinesin-1 motility causes defects in and damage to the microtubule lattice in cells. While cells have the capacity to repair lattice damage, conditions that exceed this capacity result in microtubule breakage and fragmentation and may contribute to human disease.
Collapse
Affiliation(s)
- Breane G Budaitis
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109, USA; Department of Cell & Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Somayesadat Badieyan
- Department of Biological Chemistry and Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Yang Yue
- Department of Cell & Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - T Lynne Blasius
- Department of Cell & Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Dana N Reinemann
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37240, USA
| | - Matthew J Lang
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37240, USA
| | - Michael A Cianfrocco
- Department of Biological Chemistry and Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Kristen J Verhey
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109, USA; Department of Cell & Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA.
| |
Collapse
|
8
|
Kumari D, Ray K. Phosphoregulation of Kinesins Involved in Long-Range Intracellular Transport. Front Cell Dev Biol 2022; 10:873164. [PMID: 35721476 PMCID: PMC9203973 DOI: 10.3389/fcell.2022.873164] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 04/29/2022] [Indexed: 12/28/2022] Open
Abstract
Kinesins, the microtubule-dependent mechanochemical enzymes, power a variety of intracellular movements. Regulation of Kinesin activity and Kinesin-Cargo interactions determine the direction, timing and flux of various intracellular transports. This review examines how phosphorylation of Kinesin subunits and adaptors influence the traffic driven by Kinesin-1, -2, and -3 family motors. Each family of Kinesins are phosphorylated by a partially overlapping set of serine/threonine kinases, and each event produces a unique outcome. For example, phosphorylation of the motor domain inhibits motility, and that of the stalk and tail domains induces cargo loading and unloading effects according to the residue and context. Also, the association of accessory subunits with cargo and adaptor proteins with the motor, respectively, is disrupted by phosphorylation. In some instances, phosphorylation by the same kinase on different Kinesins elicited opposite outcomes. We discuss how this diverse range of effects could manage the logistics of Kinesin-dependent, long-range intracellular transport.
Collapse
|
9
|
Selective motor activation in organelle transport along axons. Nat Rev Mol Cell Biol 2022; 23:699-714. [DOI: 10.1038/s41580-022-00491-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/14/2022] [Indexed: 12/17/2022]
|
10
|
Noureddine A, Paffett ML, Franco S, Chan AE, Pallikkuth S, Lidke K, Serda RE. Endolysosomal Mesoporous Silica Nanoparticle Trafficking along Microtubular Highways. Pharmaceutics 2021; 14:pharmaceutics14010056. [PMID: 35056951 PMCID: PMC8781846 DOI: 10.3390/pharmaceutics14010056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/19/2021] [Accepted: 12/21/2021] [Indexed: 11/16/2022] Open
Abstract
This study examines intra- and intercellular trafficking of mesoporous silica nanoparticles along microtubular highways, with an emphasis on intercellular bridges connecting interphase and telophase cells. The study of nanoparticle trafficking within and between cells during all phases of the cell cycle is relevant to payload destination and dilution, and impacts delivery of therapeutic or diagnostic agents. Super-resolution stochastic optical reconstruction and sub-airy unit image acquisition, the latter combined with Huygens deconvolution microscopy, enable single nanoparticle and microtubule resolution. Combined structural and functional data provide enhanced details on biological processes, with an example of mitotic inheritance during cancer cell trivision.
Collapse
Affiliation(s)
- Achraf Noureddine
- Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM 87131, USA;
| | - Michael L. Paffett
- Fluorescence Microscopy Shared Resource, University of New Mexico Comprehensive Cancer Center, Albuquerque, NM 87131, USA;
| | - Stefan Franco
- Internal Medicine, University of New Mexico Health Science Center, Albuquerque, NM 87131, USA; (S.F.); (A.E.C.)
| | - Alfonso E. Chan
- Internal Medicine, University of New Mexico Health Science Center, Albuquerque, NM 87131, USA; (S.F.); (A.E.C.)
| | - Sandeep Pallikkuth
- Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131, USA; (S.P.); (K.L.)
| | - Keith Lidke
- Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131, USA; (S.P.); (K.L.)
| | - Rita E. Serda
- Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM 87131, USA;
- Internal Medicine, University of New Mexico Health Science Center, Albuquerque, NM 87131, USA; (S.F.); (A.E.C.)
- Correspondence: ; Tel.: +1-505-272-7698
| |
Collapse
|
11
|
Shi XX, Wang PY, Chen H, Xie P. Studies of Conformational Changes of Tubulin Induced by Interaction with Kinesin Using Atomistic Molecular Dynamics Simulations. Int J Mol Sci 2021; 22:ijms22136709. [PMID: 34201478 PMCID: PMC8268240 DOI: 10.3390/ijms22136709] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/01/2021] [Accepted: 06/08/2021] [Indexed: 01/12/2023] Open
Abstract
The transition between strong and weak interactions of the kinesin head with the microtubule, which is regulated by the change of the nucleotide state of the head, is indispensable for the processive motion of the kinesin molecular motor on the microtubule. Here, using all-atom molecular dynamics simulations, the interactions between the kinesin head and tubulin are studied on the basis of the available high-resolution structural data. We found that the strong interaction can induce rapid large conformational changes of the tubulin, whereas the weak interaction cannot. Furthermore, we found that the large conformational changes of the tubulin have a significant effect on the interaction of the tubulin with the head in the weak-microtubule-binding ADP state. The calculated binding energy of the ADP-bound head to the tubulin with the large conformational changes is only about half that of the tubulin without the conformational changes.
Collapse
Affiliation(s)
- Xiao-Xuan Shi
- School of Material Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China; (X.-X.S.); (H.C.)
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
| | - Peng-Ye Wang
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
| | - Hong Chen
- School of Material Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China; (X.-X.S.); (H.C.)
| | - Ping Xie
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
- Correspondence:
| |
Collapse
|
12
|
Dimitrova-Paternoga L, Jagtap PKA, Cyrklaff A, Vaishali, Lapouge K, Sehr P, Perez K, Heber S, Löw C, Hennig J, Ephrussi A. Molecular basis of mRNA transport by a kinesin-1-atypical tropomyosin complex. Genes Dev 2021; 35:976-991. [PMID: 34140355 PMCID: PMC8247599 DOI: 10.1101/gad.348443.121] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 05/14/2021] [Indexed: 11/24/2022]
Abstract
Here, Dimitrova-Paternoga et al. present the high-resolution crystal structure of Khc–aTm1 (Drosophila kinesin-1, also called kinesin heavy chain [Khc], in complex with a putative cargo adaptor, the atypical tropomyosin [aTm1]), which mediates transport of oskar mRNA to the posterior pole of the Drosophila oocyte. They show that aTm1 binds to an evolutionarily conserved cargo binding site on Khc, demonstrate that Khc binds RNA directly, and show that aTm1 plays a stabilizing role in the interaction of Khc with RNA, which distinguishes aTm1 from classical motor adaptors. Kinesin-1 carries cargos including proteins, RNAs, vesicles, and pathogens over long distances within cells. The mechanochemical cycle of kinesins is well described, but how they establish cargo specificity is not fully understood. Transport of oskar mRNA to the posterior pole of the Drosophila oocyte is mediated by Drosophila kinesin-1, also called kinesin heavy chain (Khc), and a putative cargo adaptor, the atypical tropomyosin, aTm1. How the proteins cooperate in mRNA transport is unknown. Here, we present the high-resolution crystal structure of a Khc–aTm1 complex. The proteins form a tripartite coiled coil comprising two in-register Khc chains and one aTm1 chain, in antiparallel orientation. We show that aTm1 binds to an evolutionarily conserved cargo binding site on Khc, and mutational analysis confirms the importance of this interaction for mRNA transport in vivo. Furthermore, we demonstrate that Khc binds RNA directly and that it does so via its alternative cargo binding domain, which forms a positively charged joint surface with aTm1, as well as through its adjacent auxiliary microtubule binding domain. Finally, we show that aTm1 plays a stabilizing role in the interaction of Khc with RNA, which distinguishes aTm1 from classical motor adaptors.
Collapse
Affiliation(s)
- Lyudmila Dimitrova-Paternoga
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL) Heidelberg, 69117 Heidelberg, Germany.,Structural and Computational Biology Unit, EMBL Heidelberg, 69117 Heidelberg, Germany.,Centre for Structural Systems Biology (CSSB), Deutsches Elektronen-Synchrotron (DESY), EMBL Hamburg, 22607 Hamburg, Germany
| | | | - Anna Cyrklaff
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL) Heidelberg, 69117 Heidelberg, Germany
| | - Vaishali
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL) Heidelberg, 69117 Heidelberg, Germany.,Faculty of Biosciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Karine Lapouge
- Protein Expression and Purification Core Facility, EMBL Heidelberg, 69117 Heidelberg, Germany
| | - Peter Sehr
- Chemical Biology Core Facility, EMBL Heidelberg, 69117 Heidelberg, Germany
| | - Kathryn Perez
- Protein Expression and Purification Core Facility, EMBL Heidelberg, 69117 Heidelberg, Germany
| | - Simone Heber
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL) Heidelberg, 69117 Heidelberg, Germany
| | - Christian Löw
- Centre for Structural Systems Biology (CSSB), Deutsches Elektronen-Synchrotron (DESY), EMBL Hamburg, 22607 Hamburg, Germany
| | - Janosch Hennig
- Structural and Computational Biology Unit, EMBL Heidelberg, 69117 Heidelberg, Germany
| | - Anne Ephrussi
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL) Heidelberg, 69117 Heidelberg, Germany
| |
Collapse
|
13
|
Liu SX, Lü G, Zhang H, Geng YZ, Ji Q. Origin of the Surprising Mechanical Stability of Kinesin's Neck Coiled Coil. J Chem Theory Comput 2021; 17:1017-1029. [PMID: 33512152 DOI: 10.1021/acs.jctc.0c00566] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Kinesin-1 is a motor protein moving along a microtubule with its two identical motor heads dimerized by two neck linkers and a coiled-coil stalk. When both motor heads bind the microtubule, an internal strain is built up between the two heads, which is indispensable to ensure proper coordination of the two motor heads during kinesin-1's mechanochemical cycle. The internal strain forms a tensile force along the neck linker that tends to unwind the neck coiled coil (NCC). Experiments showed that the kinesin-1's NCC has a high antiunwinding ability compared with conventional coiled coils, which was mainly attributed to the enhanced hydrophobic pressure arising from the unconventional sequence of kinesin-1's NCC. However, hydrophobic pressure cannot provide the shearing force which is needed to balance the tensile force on the interface between two helices. To find out the true origin of the mechanical stability of kinesin-1's NCC, we perform a novel and detailed mechanical analysis for the system based on molecular dynamics simulation at an atomic level. We find that the needed shearing force is provided by a buckle structure formed by two tyrosines which form effective steric hindrance in the presence of tensile forces. The tensile force is balanced by the tensile direction component of the contact force between the two tyrosines which forms the shearing force. The hydrophobic pressure balances the other component of the contact force perpendicular to the tensile direction. The antiunwinding strength of NCC is defined by the maximum shearing force, which is finally determined by the hydrophobic pressure. Kinesin-1 uses residues with plane side chains, tryptophans and tyrosines, to form the hydrophobic center and to shorten the interhelix distance so that a high antiunwinding strength is obtained. The special design of NCC ensures exquisite cooperation of steric hindrance and hydrophobic pressure that results in the surprising mechanical stability of NCC.
Collapse
Affiliation(s)
- Shu-Xia Liu
- Institute of Biophysics, Hebei University of Technology, Tianjin 300401, China
| | - Gang Lü
- Mathematical and Physical Science School, North China Electric Power University, Baoding 071003, China
| | - Hui Zhang
- School of Science, Hebei University of Technology, Tianjin 300401, China
| | - Yi-Zhao Geng
- Institute of Biophysics, Hebei University of Technology, Tianjin 300401, China.,School of Science, Hebei University of Technology, Tianjin 300401, China
| | - Qing Ji
- Institute of Biophysics, Hebei University of Technology, Tianjin 300401, China.,School of Science, Hebei University of Technology, Tianjin 300401, China.,State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China
| |
Collapse
|