1
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Duan D, Lyu W, Chai P, Ma S, Wu K, Wu C, Xiong Y, Sestan N, Zhang K, Koleske AJ. Abl2 repairs microtubules and phase separates with tubulin to promote microtubule nucleation. Curr Biol 2023; 33:4582-4598.e10. [PMID: 37858340 PMCID: PMC10877310 DOI: 10.1016/j.cub.2023.09.018] [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: 02/11/2023] [Revised: 07/07/2023] [Accepted: 09/06/2023] [Indexed: 10/21/2023]
Abstract
Abl family kinases are evolutionarily conserved regulators of cell migration and morphogenesis. Genetic experiments in Drosophila suggest that Abl family kinases interact functionally with microtubules to regulate axon guidance and neuronal morphogenesis. Vertebrate Abl2 binds to microtubules and promotes their plus-end elongation, both in vitro and in cells, but the molecular mechanisms by which Abl2 regulates microtubule (MT) dynamics are unclear. We report here that Abl2 regulates MT assembly via condensation and direct interactions with both the MT lattice and tubulin dimers. We find that Abl2 promotes MT nucleation, which is further facilitated by the ability of the Abl2 C-terminal half to undergo liquid-liquid phase separation (LLPS) and form co-condensates with tubulin. Abl2 binds to regions adjacent to MT damage, facilitates MT repair via fresh tubulin recruitment, and increases MT rescue frequency and lifetime. Cryo-EM analyses strongly support a model in which Abl2 engages tubulin C-terminal tails along an extended MT lattice conformation at damage sites to facilitate repair via fresh tubulin recruitment. Abl2Δ688-790, which closely mimics a naturally occurring splice isoform, retains binding to the MT lattice but does not bind tubulin, promote MT nucleation, or increase rescue frequency. In COS-7 cells, MT reassembly after nocodazole treatment is greatly slowed in Abl2 knockout COS-7 cells compared with wild-type cells, and these defects are rescued by re-expression of Abl2, but not Abl2Δ688-790. We propose that Abl2 locally concentrates tubulin to promote MT nucleation and recruits it to defects in the MT lattice to enable repair and rescue.
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Affiliation(s)
- Daisy Duan
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Wanqing Lyu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Pengxin Chai
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Shaojie Ma
- Department of Neuroscience, Yale University, New Haven, CT 06510, USA
| | - Kuanlin Wu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Chunxiang Wu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Yong Xiong
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Nenad Sestan
- Department of Neuroscience, Yale University, New Haven, CT 06510, USA; Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT 06510, USA; Department of Comparative Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale School of Medicine, New Haven, CT 06510, USA; Yale Child Study Center, Yale School of Medicine, New Haven, CT 06510, USA
| | - Kai Zhang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Anthony J Koleske
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA; Department of Neuroscience, Yale University, New Haven, CT 06510, USA.
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2
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Wang X, Bigman LS, Greenblatt HM, Yu B, Levy Y, Iwahara J. Negatively charged, intrinsically disordered regions can accelerate target search by DNA-binding proteins. Nucleic Acids Res 2023; 51:4701-4712. [PMID: 36774964 PMCID: PMC10250230 DOI: 10.1093/nar/gkad045] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 01/03/2023] [Accepted: 01/17/2023] [Indexed: 02/14/2023] Open
Abstract
In eukaryotes, many DNA/RNA-binding proteins possess intrinsically disordered regions (IDRs) with large negative charge, some of which involve a consecutive sequence of aspartate (D) or glutamate (E) residues. We refer to them as D/E repeats. The functional role of D/E repeats is not well understood, though some of them are known to cause autoinhibition through intramolecular electrostatic interaction with functional domains. In this work, we investigated the impacts of D/E repeats on the target DNA search kinetics for the high-mobility group box 1 (HMGB1) protein and the artificial protein constructs of the Antp homeodomain fused with D/E repeats of varied lengths. Our experimental data showed that D/E repeats of particular lengths can accelerate the target association in the overwhelming presence of non-functional high-affinity ligands ('decoys'). Our coarse-grained molecular dynamics (CGMD) simulations showed that the autoinhibited proteins can bind to DNA and transition into the uninhibited complex with DNA through an electrostatically driven induced-fit process. In conjunction with the CGMD simulations, our kinetic model can explain how D/E repeats can accelerate the target association process in the presence of decoys. This study illuminates an unprecedented role of the negatively charged IDRs in the target search process.
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Affiliation(s)
- Xi Wang
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-1068, USA
| | - Lavi S Bigman
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Harry M Greenblatt
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Binhan Yu
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-1068, USA
| | - Yaakov Levy
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Junji Iwahara
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-1068, USA
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3
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Chao L, Yang S, Li H, Long C, Xi Q, Zuo Y. Competitive binding of TET1 and DNMT3A/B cooperates the DNA methylation pattern in human embryonic stem cells. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2022; 1865:194861. [PMID: 35998875 DOI: 10.1016/j.bbagrm.2022.194861] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 08/06/2022] [Accepted: 08/12/2022] [Indexed: 06/15/2023]
Abstract
DNMT3A/B and TET1 play indispensable roles in regulating DNA methylation that undergoes extensive reprogramming during mammalian embryogenesis. Yet the competitive and cooperative relationships between TET1 and DNMT3A/B remain largely unknown in the human embryonic stem cells. Here, we revealed that the main DNA-binding domain of TET1 contains more positive charges by using charge reduction of amino acid alphabet, followed by DNMT3A and DNMT3B. The genome-wide binding profiles showed that TET1 prefers binding to the proximal promoters and CpG islands compared with DNMT3A/B. Moreover, the binding regions of these three transcription factors can be divided into specific and co-binding regions. And a stronger inhibitory effect of DNMT3A on TET1 demethylation was observed in co-binding regions. Furthermore, we integrated TET1 knockout data to further discuss the competitive binding patterns of TET1 and DNMT3A/B. The lack of TET1 increased the occupation of DNMT3A/B at the specific binding regions of TET1 causing focal hypermethylation. The knockout of TET1 was also accompanied by a reduction of DNMT3A/B binding in the co-binding regions, further confirming the cooperative binding function between TET1 and DNMT3A/B. In conclusion, our studies found that the competitive binding of TET1 and DNMT3A/B cooperatively shapes the global DNA methylation pattern in human embryonic stem cells.
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Affiliation(s)
- Lemuge Chao
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, College of Life Sciences, Inner Mongolia University, Hohhot 010070, China
| | - Siqi Yang
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, College of Life Sciences, Inner Mongolia University, Hohhot 010070, China
| | - Hanshuang Li
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, College of Life Sciences, Inner Mongolia University, Hohhot 010070, China
| | - Chunshen Long
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, College of Life Sciences, Inner Mongolia University, Hohhot 010070, China
| | - Qilemuge Xi
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, College of Life Sciences, Inner Mongolia University, Hohhot 010070, China
| | - Yongchun Zuo
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, College of Life Sciences, Inner Mongolia University, Hohhot 010070, China..
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4
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Bigman LS, Iwahara J, Levy Y. Negatively Charged Disordered Regions are Prevalent and Functionally Important Across Proteomes. J Mol Biol 2022; 434:167660. [PMID: 35659505 DOI: 10.1016/j.jmb.2022.167660] [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: 02/28/2022] [Revised: 05/20/2022] [Accepted: 05/24/2022] [Indexed: 01/12/2023]
Abstract
Intrinsically disordered regions (IDRs) of proteins are often characterized by a high fraction of charged residues, but differ in their overall net charge and in the organization of the charged residues. The function-encoding information stored via IDR charge composition and organization remains elusive. Here, we aim to decipher the sequence-function relationship in IDRs by presenting a comprehensive bioinformatic analysis of the charge properties of IDRs in the human, mouse, and yeast proteomes. About 50% of the proteins comprise at least a single IDR, which is either positively or negatively charged. Highly negatively charged IDRs are longer and possess greater net charge per residue compared with highly positively charged IDRs. A striking difference between positively and negatively charged IDRs is the characteristics of the repeated units, specifically, of consecutive Lys or Arg residues (K/R repeats) and Asp or Glu (D/E repeats) residues. D/E repeats are found to be about five times longer than K/R repeats, with the longest found containing 49 residues. Long stretches of consecutive D and E are found to be more prevalent in nucleic acid-related proteins. They are less common in prokaryotes, and in eukaryotes their abundance increases with genome size. The functional role of D/E repeats and the profound differences between them and K/R repeats are discussed.
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Affiliation(s)
- Lavi S Bigman
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel. https://twitter.com/LaviBigman
| | - Junji Iwahara
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Yaakov Levy
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel.
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5
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Bujak Ł, Holanová K, García Marín A, Henrichs V, Barvík I, Braun M, Lánský Z, Piliarik M. Fast Leaps between Millisecond Confinements Govern Ase1 Diffusion along Microtubules. SMALL METHODS 2021; 5:e2100370. [PMID: 34927934 DOI: 10.1002/smtd.202100370] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 07/24/2021] [Indexed: 06/14/2023]
Abstract
Diffusion is the most fundamental mode of protein translocation within cells. Confined diffusion of proteins along the electrostatic potential constituted by the surface of microtubules, although modeled meticulously in molecular dynamics simulations, has not been experimentally observed in real-time. Here, interferometric scattering microscopy is used to directly visualize the movement of the microtubule-associated protein Ase1 along the microtubule surface at nanometer and microsecond resolution. Millisecond confinements of Ase1 and fast leaps between these positions of dwelling preferentially occurring along the microtubule protofilaments are resolved, revealing Ase1's mode of diffusive translocation along the microtubule's periodic surface. The derived interaction potential closely matches the tubulin-dimer periodicity and the distribution of the electrostatic potential on the microtubule lattice. It is anticipated that mapping the interaction landscapes for different proteins on microtubules, finding plausible energetic barriers of different positioning and heights, can provide valuable insights into regulating the dynamics of essential cytoskeletal processes, such as intracellular cargo trafficking, cell division, and morphogenesis, all of which rely on diffusive translocation of proteins along microtubules.
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Affiliation(s)
- Łukasz Bujak
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 1014/57, Prague, 18251, Czech Republic
| | - Kristýna Holanová
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 1014/57, Prague, 18251, Czech Republic
| | - Antonio García Marín
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 1014/57, Prague, 18251, Czech Republic
| | - Verena Henrichs
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, Vestec, 25250, Czech Republic
| | - Ivan Barvík
- Faculty of Mathematics and Physics, Institute of Physics, Charles University, Ke Karlovu 2026/5, Prague, 12116, Czech Republic
| | - Marcus Braun
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, Vestec, 25250, Czech Republic
| | - Zdeněk Lánský
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, Vestec, 25250, Czech Republic
| | - Marek Piliarik
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 1014/57, Prague, 18251, Czech Republic
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6
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Wang X, Greenblatt HM, Bigman LS, Yu B, Pletka CC, Levy Y, Iwahara J. Dynamic Autoinhibition of the HMGB1 Protein via Electrostatic Fuzzy Interactions of Intrinsically Disordered Regions. J Mol Biol 2021; 433:167122. [PMID: 34181980 DOI: 10.1016/j.jmb.2021.167122] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 06/03/2021] [Accepted: 06/22/2021] [Indexed: 10/21/2022]
Abstract
Highly negatively charged segments containing only aspartate or glutamate residues ("D/E repeats") are found in many eukaryotic proteins. For example, the C-terminal 30 residues of the HMGB1 protein are entirely D/E repeats. Using nuclear magnetic resonance (NMR), fluorescence, and computational approaches, we investigated how the D/E repeats causes the autoinhibition of HMGB1 against its specific binding to cisplatin-modified DNA. By varying ionic strength in a wide range (40-900 mM), we were able to shift the conformational equilibrium between the autoinhibited and uninhibited states toward either of them to the full extent. This allowed us to determine the macroscopic and microscopic equilibrium constants for the HMGB1 autoinhibition at various ionic strengths. At a macroscopic level, a model involving the autoinhibited and uninhibited states can explain the salt concentration-dependent binding affinity data. Our data at a microscopic level show that the D/E repeats and other parts of HMGB1 undergo electrostatic fuzzy interactions, each of which is weaker than expected from the macroscopic autoinhibitory effect. This discrepancy suggests that the multivalent nature of the fuzzy interactions enables strong autoinhibition at a macroscopic level despite the relatively weak intramolecular interaction at each site. Both experimental and computational data suggest that the D/E repeats interact preferentially with other intrinsically disordered regions (IDRs) of HMGB1. We also found that mutations mimicking post-translational modifications relevant to nuclear export of HMGB1 can moderately modulate DNA-binding affinity, possibly by impacting the autoinhibition. This study illuminates a functional role of the fuzzy interactions of D/E repeats.
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Affiliation(s)
- Xi Wang
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-1068, USA
| | - Harry M Greenblatt
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Lavi S Bigman
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Binhan Yu
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-1068, USA
| | - Channing C Pletka
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-1068, USA
| | - Yaakov Levy
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel.
| | - Junji Iwahara
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-1068, USA.
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7
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Bigman LS, Levy Y. Modulating Microtubules: A Molecular Perspective on the Effects of Tail Modifications. J Mol Biol 2021; 433:166988. [PMID: 33865866 DOI: 10.1016/j.jmb.2021.166988] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 04/07/2021] [Accepted: 04/07/2021] [Indexed: 10/21/2022]
Abstract
Microtubules (MTs), an essential component of the eukaryotic cytoskeleton, are a lattice of polymerized tubulin dimers and are crucial for various cellular processes. The genetic and chemical diversity of tubulin and their disordered tails gives rise to a "tubulin code". The functional role of tubulin post-translational modifications (PTMs), which contribute to the chemical diversity of the tubulin code, is gradually being unraveled. However, variation in the length and spatial organization of tubulin poly-modifications leads to an enormous combinatorial PTM space, which is difficult to study experimentally. Hence, the impact of the combinatorial tubulin PTM space on the biophysical properties of tubulin tails and their interactions with other proteins remains elusive. Here, we combine all-atom and coarse-grained molecular dynamics simulations to elucidate the biophysical implications of the large combinatorial tubulin PTM space in the context of an MT lattice. We find that tail-body interactions are more dominant in the tubulin dimer than in an MT lattice, and are more significant for the tails of α compared with β tubulin. In addition, polyglutamylation, but not polyglycylation, expands the dimensions of the tubulin tails. Polyglutamylation also leads to a decrease in the diffusion rate of MT-associated protein EB1 on MTs, while polyglycylation often increases diffusion rate. These observations are generally not sensitive to the organization of the polymodifications. The effect of PTMs on MT charge density and tail dynamics are also discussed. Overall, this study presents a molecular quantification of the biophysical properties of tubulin tails and their polymodifications, and provides predictions on the functional importance of tubulin PTMs.
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Affiliation(s)
- Lavi S Bigman
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yaakov Levy
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel.
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8
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Bigman LS, Greenblatt HM, Levy Y. What Are the Molecular Requirements for Protein Sliding along DNA? J Phys Chem B 2021; 125:3119-3131. [PMID: 33754737 PMCID: PMC8041311 DOI: 10.1021/acs.jpcb.1c00757] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
![]()
DNA-binding proteins rely on linear
diffusion along the longitudinal
DNA axis, supported by their nonspecific electrostatic affinity for
DNA, to search for their target recognition sites. One may therefore
expect that the ability to engage in linear diffusion along DNA is
universal to all DNA-binding proteins, with the detailed biophysical
characteristics of that diffusion differing between proteins depending
on their structures and functions. One key question is whether the
linear diffusion mechanism is defined by translation coupled with
rotation, a mechanism that is often termed sliding. We conduct coarse-grained
and atomistic molecular dynamics simulations to investigate the minimal
requirements for protein sliding along DNA. We show that coupling,
while widespread, is not universal. DNA-binding proteins that slide
along DNA transition to uncoupled translation–rotation (i.e.,
hopping) at higher salt concentrations. Furthermore, and consistently
with experimental reports, we find that the sliding mechanism is the
less dominant mechanism for some DNA-binding proteins, even at low
salt concentrations. In particular, the toroidal PCNA protein is shown
to follow the hopping rather than the sliding mechanism.
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Affiliation(s)
- Lavi S Bigman
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Harry M Greenblatt
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yaakov Levy
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
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9
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Pal A, Greenblatt HM, Levy Y. Prerecognition Diffusion Mechanism of Human DNA Mismatch Repair Proteins along DNA: Msh2-Msh3 versus Msh2-Msh6. Biochemistry 2020; 59:4822-4832. [PMID: 33319999 PMCID: PMC7872316 DOI: 10.1021/acs.biochem.0c00669] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
DNA
mismatch repair (MMR) is an important postreplication process
that eliminates mispaired or unpaired nucleotides to ensure genomic
replication fidelity. In humans, Msh2-Msh6 and Msh2-Msh3 are the two
mismatch repair initiation factors that recognize DNA lesions. While
X-ray crystal structures exist for these proteins in complex with
DNA lesions, little is known about their structures during the initial
search along nonspecific double-stranded DNA, because they are short-lived
and difficult to determine experimentally. In this study, various
computational approaches were used to sidestep these difficulties.
All-atom and coarse-grained simulations based on the crystal structures
of Msh2-Msh3 and Msh2-Msh6 showed no translation along the DNA, suggesting
that the initial search conformation differs from the lesion-bound
crystal structure. We modeled probable search-mode structures of MSH
proteins and showed, using coarse-grained molecular dynamics simulations,
that they can perform rotation-coupled diffusion on DNA, which is
a suitable and efficient search mechanism for their function and one
predicted earlier by fluorescence resonance energy transfer and fluorescence
microscopy studies. This search mechanism is implemented by electrostatic
interactions among the mismatch-binding domain (MBD), the clamp domains,
and the DNA backbone. During simulations, their diffusion rate did
not change significantly with an increasing salt concentration, which
is consistent with observations from experimental studies. When the
gap between their DNA-binding clamps was increased, Msh2-Msh3 diffused
mostly via the clamp domains while Msh2-Msh6 still diffused using
the MBD, reproducing the experimentally measured lower diffusion coefficient
of Msh2-Msh6. Interestingly, Msh2-Msh3 was capable of dissociating
from the DNA, whereas Msh2-Msh6 always diffused on the DNA duplex.
This is consistent with the experimental observation that Msh2-Msh3,
unlike Msh2-Msh6, can overcome obstacles such as nucleosomes. Our
models provide a molecular picture of the different mismatch search
mechanisms undertaken by Msh2-Msh6 and Msh2-Msh3, despite the similarity
of their structures.
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Affiliation(s)
- Arumay Pal
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Harry M Greenblatt
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yaakov Levy
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
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10
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Lukatsky DB. Understanding the Robustness of Protein Diffusion on DNA and Microtubules. Biophys J 2020; 118:2870-2871. [PMID: 32470323 DOI: 10.1016/j.bpj.2020.05.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 05/07/2020] [Indexed: 11/19/2022] Open
Affiliation(s)
- David B Lukatsky
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
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