1
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Jongsma MLM, Bakker N, Voortman LM, Koning RI, Bos E, Akkermans JJLL, Janssen L, Neefjes J. Systems mapping of bidirectional endosomal transport through the crowded cell. Curr Biol 2024:S0960-9822(24)01138-2. [PMID: 39276769 DOI: 10.1016/j.cub.2024.08.026] [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: 02/16/2024] [Revised: 07/02/2024] [Accepted: 08/15/2024] [Indexed: 09/17/2024]
Abstract
Kinesin and dynein-dynactin motors move endosomes and other vesicles bidirectionally along microtubules, a process mainly studied under in vitro conditions. Here, we provide a physiological bidirectional transport model following color-coded, endogenously tagged transport-related proteins as they move through a crowded cellular environment. Late endosomes (LEs) surf bidirectionally on Protrudin-enriched endoplasmic reticulum (ER) membrane contact sites, while hopping and gliding along microtubules and bypassing cellular obstacles, such as mitochondria. During bidirectional transport, late endosomes do not switch between opposing Rab7 GTPase effectors, RILP and FYCO1, or their associated dynein and KIF5B motor proteins, respectively. In the endogenous setting, far fewer motors associate with endosomal membranes relative to effectors, implying coordination of transport with other aspects of endosome physiology through GTPase-regulated mechanisms. We find that directionality of transport is provided in part by various microtubule-associated proteins (MAPs), including MID1, EB1, and CEP169, which recruit Lis1-activated dynein motors to microtubule plus ends for transport of early and late endosomal populations. At these microtubule plus ends, activated dynein motors encounter the dynactin subunit p150glued and become competent for endosomal capture and minus-end movement in collaboration with membrane-associated Rab7-RILP. We show that endosomes surf over the ER through the crowded cell and move bidirectionally under the control of MAPs for motor activation and through motor replacement and capture by endosomal anchors.
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Affiliation(s)
- Marlieke L M Jongsma
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands.
| | - Nina Bakker
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands
| | - Lenard M Voortman
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands
| | - Roman I Koning
- Electron Microscopy Facility, Department of Cell and Chemical Biology, Leiden University Medical Centre, P.O. Box 9600, 2300 RC Leiden, the Netherlands
| | - Erik Bos
- Electron Microscopy Facility, Department of Cell and Chemical Biology, Leiden University Medical Centre, P.O. Box 9600, 2300 RC Leiden, the Netherlands
| | - Jimmy J L L Akkermans
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands
| | - Lennert Janssen
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands
| | - Jacques Neefjes
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands.
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2
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Fellows AD, Bruntraeger M, Burgold T, Bassett AR, Carter AP. Dynein and dynactin move long-range but are delivered separately to the axon tip. J Cell Biol 2024; 223:e202309084. [PMID: 38407313 PMCID: PMC10896695 DOI: 10.1083/jcb.202309084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 01/17/2024] [Accepted: 02/05/2024] [Indexed: 02/27/2024] Open
Abstract
Axonal transport is essential for neuronal survival. This is driven by microtubule motors including dynein, which transports cargo from the axon tip back to the cell body. This function requires its cofactor dynactin and regulators LIS1 and NDEL1. Due to difficulties imaging dynein at a single-molecule level, it is unclear how this motor and its regulators coordinate transport along the length of the axon. Here, we use a neuron-inducible human stem cell line (NGN2-OPTi-OX) to endogenously tag dynein components and visualize them at a near-single molecule regime. In the retrograde direction, we find that dynein and dynactin can move the entire length of the axon (>500 µm). Furthermore, LIS1 and NDEL1 also undergo long-distance movement, despite being mainly implicated with the initiation of dynein transport. Intriguingly, in the anterograde direction, dynein/LIS1 moves faster than dynactin/NDEL1, consistent with transport on different cargos. Therefore, neurons ensure efficient transport by holding dynein/dynactin on cargos over long distances but keeping them separate until required.
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Affiliation(s)
- Alexander D Fellows
- Division of Structural Studies, Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Thomas Burgold
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, UK
| | | | - Andrew P Carter
- Division of Structural Studies, Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
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3
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Zhang J, Qiu R, Xie S, Rasmussen M, Xiang X. VezA/vezatin facilitates proper assembly of the dynactin complex in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.19.590248. [PMID: 38659795 PMCID: PMC11042379 DOI: 10.1101/2024.04.19.590248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Cytoplasmic dynein-mediated intracellular transport needs the multi-component dynactin complex for cargo binding and motor activation. However, cellular factors involved in dynactin assembly remain unexplored. Here we found in Aspergillus nidulans that the vezatin homolog VezA is important for dynactin assembly. VezA affects the microtubule plus-end accumulation of dynein before cargo binding and cargo adapter-mediated dynein activation, two processes that both need dynactin. The dynactin complex contains multiple components including an Arp1 (actin-related protein 1) mini-filament associated with a pointed-end sub-complex. VezA physically interacts with dynactin either directly or indirectly via the Arp1 mini-filament and its pointed-end sub-complex. Loss of VezA causes a defect in dynactin integrity, most likely by affecting the connection between the Arp1 mini-filament and its pointed-end sub-complex. Using various dynactin mutants, we further revealed that assembly of the dynactin complex must be highly coordinated. Together, these results shed important new light on dynactin assembly in vivo.
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Affiliation(s)
- Jun Zhang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
| | - Rongde Qiu
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
| | - Sean Xie
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
- Montgomery Blair High School, Silver Spring, Maryland, USA
| | - Megan Rasmussen
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
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4
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Park JG, Jeon H, Hwang KY, Cha SS, Han RT, Cho H, Lee IG. Cargo specificity, regulation, and therapeutic potential of cytoplasmic dynein. Exp Mol Med 2024; 56:827-835. [PMID: 38556551 PMCID: PMC11059388 DOI: 10.1038/s12276-024-01200-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 01/05/2024] [Accepted: 01/10/2024] [Indexed: 04/02/2024] Open
Abstract
Intracellular retrograde transport in eukaryotic cells relies exclusively on the molecular motor cytoplasmic dynein 1. Unlike its counterpart, kinesin, dynein has a single isoform, which raises questions about its cargo specificity and regulatory mechanisms. The precision of dynein-mediated cargo transport is governed by a multitude of factors, including temperature, phosphorylation, the microtubule track, and interactions with a family of activating adaptor proteins. Activating adaptors are of particular importance because they not only activate the unidirectional motility of the motor but also connect a diverse array of cargoes with the dynein motor. Therefore, it is unsurprising that dysregulation of the dynein-activating adaptor transport machinery can lead to diseases such as spinal muscular atrophy, lower extremity, and dominant. Here, we discuss dynein motor motility within cells and in in vitro, and we present several methodologies employed to track the motion of the motor. We highlight several newly identified activating adaptors and their roles in regulating dynein. Finally, we explore the potential therapeutic applications of manipulating dynein transport to address diseases linked to dynein malfunction.
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Affiliation(s)
- Jin-Gyeong Park
- Biomedical Research Division, Korea Institute of Science and Technology, Seoul, 02792, South Korea
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, South Korea
| | - Hanul Jeon
- Biomedical Research Division, Korea Institute of Science and Technology, Seoul, 02792, South Korea
- Department of Chemistry & Nanoscience, Ewha Womans University, Seoul, 03760, South Korea
| | - Kwang Yeon Hwang
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, South Korea
| | - Sun-Shin Cha
- Department of Chemistry & Nanoscience, Ewha Womans University, Seoul, 03760, South Korea
| | - Rafael T Han
- Biomedical Research Division, Korea Institute of Science and Technology, Seoul, 02792, South Korea
- KHU-KIST Department of Converging Science and Technology, Kyunghee University, Seoul, 02447, South Korea
| | - Hyesung Cho
- Extreme Materials Research Center, Korea Institute of Science and Technology, Seoul, 02792, South Korea
| | - In-Gyun Lee
- Biomedical Research Division, Korea Institute of Science and Technology, Seoul, 02792, South Korea.
- Department of Biological Chemistry, University of Science and Technology, Daejeon, 34113, South Korea.
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5
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Kusakci E, Htet ZM, Zhao Y, Gillies JP, Reck-Peterson SL, Yildiz A. Lis1 slows force-induced detachment of cytoplasmic dynein from microtubules. Nat Chem Biol 2024; 20:521-529. [PMID: 37919547 PMCID: PMC11164236 DOI: 10.1038/s41589-023-01464-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 09/29/2023] [Indexed: 11/04/2023]
Abstract
Lis1 is a key cofactor for the assembly of active cytoplasmic dynein complexes that transport cargo along microtubules. Lis1 binds to the AAA+ ring and stalk of dynein and slows dynein motility, but the underlying mechanism has remained unclear. Using single-molecule imaging and optical trapping assays, we investigated how Lis1 binding affects the motility and force generation of yeast dynein in vitro. We showed that Lis1 slows motility by binding to the AAA+ ring of dynein, not by serving as a roadblock or tethering dynein to microtubules. Lis1 binding also does not affect force generation, but it induces prolonged stalls and reduces the asymmetry in the force-induced detachment of dynein from microtubules. The mutagenesis of the Lis1-binding sites on the dynein stalk partially recovers this asymmetry but does not restore dynein velocity. These results suggest that Lis1-stalk interaction slows the detachment of dynein from microtubules by interfering with the stalk sliding mechanism.
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Affiliation(s)
- Emre Kusakci
- Graduate Group in Biophysics, University of California Berkeley, Berkeley, CA, USA
| | - Zaw Min Htet
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, USA
| | - Yuanchang Zhao
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, USA
- Physics Department, University of California Berkeley, Berkeley, CA, USA
| | - John P Gillies
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
| | - Samara L Reck-Peterson
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
- Department of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Ahmet Yildiz
- Graduate Group in Biophysics, University of California Berkeley, Berkeley, CA, USA.
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, USA.
- Physics Department, University of California Berkeley, Berkeley, CA, USA.
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6
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Zhang J, Qiu R, Bieger BD, Oakley CE, Oakley BR, Egan MJ, Xiang X. Aspergillus SUMOylation mutants exhibit chromosome segregation defects including chromatin bridges. Genetics 2023; 225:iyad169. [PMID: 37724751 PMCID: PMC10697819 DOI: 10.1093/genetics/iyad169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/29/2023] [Accepted: 09/07/2023] [Indexed: 09/21/2023] Open
Abstract
Functions of protein SUMOylation remain incompletely understood in different cell types. Via forward genetics, here we identified ubaBQ247*, a loss-of-function mutation in a SUMO activation enzyme UbaB in the filamentous fungus Aspergillus nidulans. The ubaBQ247*, ΔubaB, and ΔsumO mutants all produce abnormal chromatin bridges, indicating the importance of SUMOylation in the completion of chromosome segregation. The bridges are enclosed by nuclear membrane containing peripheral nuclear pore complex proteins that normally get dispersed during mitosis, and the bridges are also surrounded by cytoplasmic microtubules typical of interphase cells. Time-lapse sequences further indicate that most bridges persist through interphase prior to the next mitosis, and anaphase chromosome segregation can produce new bridges that persist into the next interphase. When the first mitosis happens at a higher temperature of 42°C, SUMOylation deficiency produces not only chromatin bridges but also many abnormally shaped single nuclei that fail to divide. UbaB-GFP localizes to interphase nuclei just like the previously studied SumO-GFP, but the nuclear signals disappear during mitosis when the nuclear pores are partially open, and the signals reappear after mitosis. The nuclear localization is consistent with many SUMO targets being nuclear proteins. Finally, although the budding yeast SUMOylation machinery interacts with LIS1, a protein critical for dynein activation, loss of SUMOylation does not cause any obvious defect in dynein-mediated transport of nuclei and early endosomes, indicating that SUMOylation is unnecessary for dynein activation in A. nidulans.
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Affiliation(s)
- Jun Zhang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences-F. Edward Hébert School of Medicine, Bethesda, MD 20814, USA
| | - Rongde Qiu
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences-F. Edward Hébert School of Medicine, Bethesda, MD 20814, USA
| | - Baronger D Bieger
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, AR 72701, USA
| | - C Elizabeth Oakley
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
| | - Berl R Oakley
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
| | - Martin J Egan
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, AR 72701, USA
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences-F. Edward Hébert School of Medicine, Bethesda, MD 20814, USA
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7
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Zhao Y, Oten S, Yildiz A. Nde1 promotes Lis1-mediated activation of dynein. Nat Commun 2023; 14:7221. [PMID: 37940657 PMCID: PMC10632352 DOI: 10.1038/s41467-023-42907-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 10/24/2023] [Indexed: 11/10/2023] Open
Abstract
Cytoplasmic dynein drives the motility and force generation functions towards the microtubule minus end. The assembly of dynein with dynactin and a cargo adaptor in an active transport complex is facilitated by Lis1 and Nde1/Ndel1. Recent studies proposed that Lis1 relieves dynein from its autoinhibited conformation, but the physiological function of Nde1/Ndel1 remains elusive. Here, we investigate how human Nde1 and Lis1 regulate the assembly and subsequent motility of mammalian dynein using in vitro reconstitution and single molecule imaging. We find that Nde1 recruits Lis1 to autoinhibited dynein and promotes Lis1-mediated assembly of dynein-dynactin adaptor complexes. Nde1 can compete with the α2 subunit of platelet activator factor acetylhydrolase 1B (PAF-AH1B) for the binding of Lis1, which suggests that Nde1 may disrupt PAF-AH1B recruitment of Lis1 as a noncatalytic subunit, thus promoting Lis1 binding to dynein. Before the initiation of motility, the association of dynactin with dynein triggers the dissociation of Nde1 from dynein by competing against Nde1 binding to the dynein intermediate chain. Our results provide a mechanistic explanation for how Nde1 and Lis1 synergistically activate the dynein transport machinery.
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Affiliation(s)
- Yuanchang Zhao
- Physics Department, University of California, Berkeley, CA, 94709, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, 94709, USA
| | - Sena Oten
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, 94709, USA
| | - Ahmet Yildiz
- Physics Department, University of California, Berkeley, CA, 94709, USA.
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, 94709, USA.
- Biophysics Graduate Group, University of California, Berkeley, CA, 94709, USA.
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8
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Okada K, Iyer BR, Lammers LG, Gutierrez PA, Li W, Markus SM, McKenney RJ. Conserved roles for the dynein intermediate chain and Ndel1 in assembly and activation of dynein. Nat Commun 2023; 14:5833. [PMID: 37730751 PMCID: PMC10511499 DOI: 10.1038/s41467-023-41466-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 08/31/2023] [Indexed: 09/22/2023] Open
Abstract
Processive transport by the microtubule motor cytoplasmic dynein requires the regulated assembly of a dynein-dynactin-adapter complex. Interactions between dynein and dynactin were initially ascribed to the dynein intermediate chain N-terminus and the dynactin subunit p150Glued. However, recent cryo-EM structures have not resolved this interaction, questioning its importance. The intermediate chain also interacts with Nde1/Ndel1, which compete with p150Glued for binding. We reveal that the intermediate chain N-terminus is a critical evolutionarily conserved hub that interacts with dynactin and Ndel1, the latter of which recruits LIS1 to drive complex assembly. In additon to revealing that the intermediate chain N-terminus is likely bound to p150Glued in active transport complexes, our data support a model whereby Ndel1-LIS1 must dissociate prior to LIS1 being handed off to dynein in temporally discrete steps. Our work reveals previously unknown steps in the dynein activation pathway, and provide insight into the integrated activities of LIS1/Ndel1 and dynactin/cargo-adapters.
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Affiliation(s)
- Kyoko Okada
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, 95616, USA
| | - Bharat R Iyer
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Lindsay G Lammers
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Pedro A Gutierrez
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, 95616, USA
- Department of Biological Sciences, Columbia University, New York, NY, 10027, USA
| | - Wenzhe Li
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, 95616, USA
| | - Steven M Markus
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, 80523, USA.
| | - Richard J McKenney
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, 95616, USA.
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9
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Zhao Y, Oten S, Yildiz A. Nde1 Promotes Lis1-Mediated Activation of Dynein. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.26.542537. [PMID: 37292665 PMCID: PMC10246013 DOI: 10.1101/2023.05.26.542537] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Cytoplasmic dynein is the primary motor that drives the motility and force generation functions towards the microtubule minus end. The activation of dynein motility requires its assembly with dynactin and a cargo adaptor. This process is facilitated by two dynein-associated factors, Lis1 and Nde1/Ndel1. Recent studies proposed that Lis1 rescues dynein from its autoinhibited conformation, but the physiological function of Nde1/Ndel1 remains elusive. Here, we investigated how human Nde1 and Lis1 regulate the assembly and subsequent motility of the mammalian dynein/dynactin complex using in vitro reconstitution and single molecule imaging. We found that Nde1 promotes the assembly of active dynein complexes in two distinct ways. Nde1 competes with the α2 subunit of platelet activator factor acetylhydrolase (PAF-AH) 1B, which recruits Lis1 as a noncatalytic subunit and prevents its binding to dynein. Second, Nde1 recruits Lis1 to autoinhibited dynein and promotes Lis1-mediated assembly of dynein-dynactin-adaptor complexes. However, excess Nde1 inhibits dynein, presumably by competing against dynactin to bind the dynein intermediate chain. The association of dynactin with dynein triggers Nde1 dissociation before the initiation of dynein motility. Our results provide a mechanistic explanation for how Nde1 and Lis1 synergistically activate the dynein transport machinery.
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Affiliation(s)
- Yuanchang Zhao
- Physics Department, University of California, Berkeley, CA, USA, 94709
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA, 94709
| | - Sena Oten
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA, 94709
| | - Ahmet Yildiz
- Physics Department, University of California, Berkeley, CA, USA, 94709
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA, 94709
- Biophysics Graduate Group, University of California, Berkeley, CA, USA, 94709
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10
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Ton WD, Wang Y, Chai P, Beauchamp-Perez C, Flint NT, Lammers LG, Xiong H, Zhang K, Markus SM. Microtubule-binding-induced allostery triggers LIS1 dissociation from dynein prior to cargo transport. Nat Struct Mol Biol 2023; 30:1365-1379. [PMID: 37322240 PMCID: PMC10590275 DOI: 10.1038/s41594-023-01010-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 04/28/2023] [Indexed: 06/17/2023]
Abstract
The lissencephaly-related protein LIS1 is a critical regulator of cytoplasmic dynein that governs motor function and intracellular localization (for example, to microtubule plus-ends). Although LIS1 binding is required for dynein activity, its unbinding prior to initiation of cargo transport is equally important, since preventing dissociation leads to dynein dysfunction. To understand whether and how dynein-LIS1 binding is modulated, we engineered dynein mutants locked in a microtubule-bound (MT-B) or microtubule-unbound (MT-U) state. Whereas the MT-B mutant exhibits low LIS1 affinity, the MT-U mutant binds LIS1 with high affinity, and as a consequence remains almost irreversibly associated with microtubule plus-ends. We find that a monomeric motor domain is sufficient to exhibit these opposing LIS1 affinities, and that this is evolutionarily conserved between yeast and humans. Three cryo-EM structures of human dynein with and without LIS1 reveal microtubule-binding induced conformational changes responsible for this regulation. Our work reveals key biochemical and structural insight into LIS1-mediated dynein activation.
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Affiliation(s)
- William D Ton
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Yue Wang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Pengxin Chai
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | | | - Nicholas T Flint
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Lindsay G Lammers
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Hao Xiong
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Kai Zhang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
| | - Steven M Markus
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA.
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11
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Azzollini S, Monfort T, Thouvenin O, Grieve K. Dynamic optical coherence tomography for cell analysis [Invited]. BIOMEDICAL OPTICS EXPRESS 2023; 14:3362-3379. [PMID: 37497511 PMCID: PMC10368035 DOI: 10.1364/boe.488929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/29/2023] [Accepted: 06/06/2023] [Indexed: 07/28/2023]
Abstract
Label-free live optical imaging of dynamic cellular and subcellular features has been made possible in recent years thanks to the advances made in optical imaging techniques, including dynamic optical coherence tomography (D-OCT) methods. These techniques analyze the temporal fluctuations of an optical signal associated with the active movements of intracellular organelles to obtain an ensemble metric recapitulating the motility and metabolic state of cells. They hence enable visualization of cells within compact, static environments and evaluate their physiology. These emerging microscopies show promise, in particular for the three-dimensional evaluation of live tissue samples such as freshly excised biopsies and 3D cell cultures. In this review, we compare the various techniques used for dynamic OCT. We give an overview of the range of applications currently being explored and discuss the future outlook and opportunities for the field.
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Affiliation(s)
- Salvatore Azzollini
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, F-75012 Paris, France
| | - Tual Monfort
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, F-75012 Paris, France
- CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, 28 rue de Charenton, F-75012 Paris, France
| | | | - Kate Grieve
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, F-75012 Paris, France
- CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, 28 rue de Charenton, F-75012 Paris, France
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12
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Songster LD, Bhuyan D, Christensen JR, Reck-Peterson SL. Woronin body hitchhiking on early endosomes is dispensable for septal localization in Aspergillus nidulans. Mol Biol Cell 2023; 34:br9. [PMID: 37017489 PMCID: PMC10295486 DOI: 10.1091/mbc.e23-01-0025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/28/2023] [Accepted: 03/28/2023] [Indexed: 04/06/2023] Open
Abstract
The proper functioning of organelles depends on their intracellular localization, mediated by motor protein-dependent transport on cytoskeletal tracks. Rather than directly associating with a motor protein, peroxisomes move by hitchhiking on motile early endosomes in the filamentous fungus Aspergillus nidulans. However, the physiological role of peroxisome hitchhiking is unclear. Peroxisome hitchhiking requires the protein PxdA, which is conserved within the fungal subphylum Pezizomycotina but absent from other fungal clades. Woronin bodies are specialized peroxisomes that are also unique to the Pezizomycotina. In these fungi, multinucleate hyphal segments are separated by incomplete cell walls called septa that possess a central pore enabling cytoplasmic exchange. Upon damage to a hyphal segment, Woronin bodies plug septal pores to prevent widespread leakage. Here, we tested whether peroxisome hitchhiking is important for Woronin body motility, distribution, and function in A. nidulans. We show that Woronin body proteins are present within all motile peroxisomes and hitchhike on PxdA-labeled early endosomes during bidirectional, long-distance movements. Loss of peroxisome hitchhiking significantly affected Woronin body distribution and motility in the cytoplasm, but Woronin body hitchhiking is ultimately dispensable for septal localization and plugging.
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Affiliation(s)
- Livia D. Songster
- Department of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093
| | - Devahuti Bhuyan
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Jenna R. Christensen
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Samara L. Reck-Peterson
- Department of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
- Howard Hughes Medical Institute, Chevy Chase, MD 20815
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13
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Zhang J, Qiu R, Bieger BD, Oakley CE, Oakley BR, Egan MJ, Xiang X. Aspergillus SUMOylation mutants have normal dynein function but exhibit chromatin bridges. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.16.537086. [PMID: 37131833 PMCID: PMC10153134 DOI: 10.1101/2023.04.16.537086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Functions of protein SUMOylation remain incompletely understood in different cell types. The budding yeast SUMOylation machinery interacts with LIS1, a protein critical for dynein activation, but dynein-pathway components were not identified as SUMO-targets in the filamentous fungus Aspergillus nidulans. Via A. nidulans forward genetics, here we identified ubaBQ247*, a loss-of-function mutation in a SUMO-activation enzyme UbaB. Colonies of the ubaBQ247*, ΔubaB and ΔsumO mutants looked similar and less healthy than the wild-type colony. In these mutants, about 10% of nuclei are connected by abnormal chromatin bridges, indicating the importance of SUMOylation in the completion of chromosome segregation. Nuclei connected by chromatin bridges are mostly in interphase, suggesting that these bridges do not prevent cell-cycle progression. UbaB-GFP localizes to interphase nuclei just like the previously studied SumO-GFP, but the nuclear signals disappear during mitosis when the nuclear pores are partially open, and the signals reappear after mitosis. The nuclear localization is consistent with many SUMO-targets being nuclear proteins, for example, topoisomerase II whose SUMOylation defect gives rise to chromatin bridges in mammalian cells. Unlike in mammalian cells, however, loss of SUMOylation in A. nidulans does not apparently affect the metaphase-to-anaphase transition, further highlighting differences in the requirements of SUMOylation in different cell types. Finally, loss of UbaB or SumO does not affect dynein- and LIS1-mediated early-endosome transport, indicating that SUMOylation is unnecessary for dynein or LIS1 function in A. nidulans.
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Affiliation(s)
- Jun Zhang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
| | - Rongde Qiu
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
| | - Baronger D. Bieger
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, AR, USA
| | - C. Elizabeth Oakley
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, USA
| | - Berl R. Oakley
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, USA
| | - Martin J. Egan
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, AR, USA
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
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14
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Qiu R, Zhang J, Xiang X. Kinesin-1 autoinhibition facilitates the initiation of dynein cargo transport. J Cell Biol 2023; 222:e202205136. [PMID: 36524956 PMCID: PMC9802684 DOI: 10.1083/jcb.202205136] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 11/04/2022] [Accepted: 12/05/2022] [Indexed: 12/23/2022] Open
Abstract
The functional significance of Kinesin-1 autoinhibition has been unclear. Kinesin-1 transports multiple cargoes including cytoplasmic dynein to microtubule plus ends. From a genetic screen for Aspergillus mutants defective in dynein-mediated early endosome transport, we identified a kinesin-1 mutation kinAK895* at the C-terminal IAK motif involved in autoinhibition. The kinA∆IAK and kinAK895E mutants exhibited a similar defect in dynein-mediated early endosome transport, verifying the importance of kinesin-1 autoinhibition in dynein-mediated transport. Kinesin-1 autoinhibition is not critical for dynein accumulation at microtubule plus ends or for the secretory vesicle cargoes of kinesin-1 to reach the hyphal tip. However, it facilitates dynein to initiate early endosome transport. This is unrelated to a direct competition between dynein and kinesin-1 on early endosomes because kinesin-3 rather than kinesin-1 drives the plus-end-directed early endosome movement. This effect of kinesin-1 autoinhibition on dynein-mediated early endosome transport is related to cargo adapter-mediated dynein activation but at a step beyond the switching of dynein from its autoinhibited conformation.
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Affiliation(s)
- Rongde Qiu
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences, F. Edward Hébert School of Medicine, Bethesda, MA, USA
| | - Jun Zhang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences, F. Edward Hébert School of Medicine, Bethesda, MA, USA
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences, F. Edward Hébert School of Medicine, Bethesda, MA, USA
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15
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Songster LD, Bhuyan D, Christensen JR, Reck-Peterson SL. Woronin bodies move dynamically and bidirectionally by hitchhiking on early endosomes in Aspergillus nidulans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.20.524968. [PMID: 36711994 PMCID: PMC9882315 DOI: 10.1101/2023.01.20.524968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The proper functioning of organelles depends on their intracellular localization, mediated by motor protein-dependent transport on cytoskeletal tracks. Rather than directly associating with a motor protein, peroxisomes move by hitchhiking on motile early endosomes in the filamentous fungus Aspergillus nidulans . However, the cellular function of peroxisome hitchhiking is unclear. Peroxisome hitchhiking requires the protein PxdA, which is conserved within the fungal subphylum Pezizomycotina, but absent from other fungal clades. Woronin bodies are specialized peroxisomes that are also unique to the Pezizomycotina. In these fungi, multinucleate hyphal segments are separated by incomplete cell walls called septa that possess a central pore enabling cytoplasmic exchange. Upon damage to a hyphal segment, Woronin bodies plug septal pores to prevent wide-spread leakage. Here, we tested if peroxisome hitchhiking is important for Woronin body motility, distribution, and function in A. nidulans . We show that Woronin body proteins are present within all motile peroxisomes and hitchhike on PxdA-labeled early endosomes during bidirectional, long-distance movements. Loss of peroxisome hitchhiking by knocking out pxdA significantly affected Woronin body distribution and motility in the cytoplasm, but Woronin body hitchhiking is ultimately dispensable for septal localization and plugging.
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Affiliation(s)
- Livia D. Songster
- Department of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA
| | - Devahuti Bhuyan
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
| | - Jenna R. Christensen
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
| | - Samara L. Reck-Peterson
- Department of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
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16
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Okada K, Iyer BR, Lammers LG, Gutierrez P, Li W, Markus SM, McKenney RJ. Conserved Roles for the Dynein Intermediate Chain and Ndel1 in Assembly and Activation of Dynein. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.13.523097. [PMID: 36711700 PMCID: PMC9882231 DOI: 10.1101/2023.01.13.523097] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Cytoplasmic dynein, the primary retrograde microtubule transport motor within cells, must be activated for processive motility through the regulated assembly of a dynein-dynactin-adapter (DDA) complex. The interaction between dynein and dynactin was initially ascribed to the N-terminus of the dynein intermediate chain (IC) and a coiled-coil of the dynactin subunit p150 Glued . However, cryo-EM structures of DDA complexes have not resolve these regions of the IC and p150 Glued , raising questions about the importance of this interaction. The IC N-terminus (ICN) also interacts with the dynein regulators Nde1/Ndel1, which compete with p150 Glued for binding to ICN. Using a combination of approaches, we reveal that the ICN plays critical, evolutionarily conserved roles in DDA assembly by interacting with dynactin and Ndel1, the latter of which recruits the DDA assembly factor LIS1 to the dynein complex. In contrast to prior models, we find that LIS1 cannot simultaneously bind to Ndel1 and dynein, indicating that LIS1 must be handed off from Ndel1 to dynein in temporally discrete steps. Whereas exogenous Ndel1 or p150 Glued disrupts DDA complex assembly in vitro , neither perturbs preassembled DDA complexes, indicating that the IC is stably bound to p150 Glued within activated DDA complexes. Our study reveals previously unknown regulatory steps in the dynein activation pathway, and provides a more complete model for how the activities of LIS1/Ndel1 and dynactin/cargo-adapters are integrated to regulate dynein motor activity.
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Affiliation(s)
- Kyoko Okada
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, USA
| | - Bharat R. Iyer
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Lindsay G. Lammers
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Pedro Gutierrez
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, USA
| | - Wenzhe Li
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, USA
| | - Steven M. Markus
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Richard J. McKenney
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, USA
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17
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Qiu R, Zhang J, McDaniel D, Peñalva MA, Xiang X. Live-Cell Imaging of Dynein-Mediated Cargo Transport in Aspergillus nidulans. Methods Mol Biol 2023; 2623:3-23. [PMID: 36602676 DOI: 10.1007/978-1-0716-2958-1_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Filamentous fungi have been used for studying long-distance transport of cargoes driven by cytoplasmic dynein. Aspergillus nidulans is a well-established genetic model organism used for studying dynein function and regulation in vivo. Here, we describe how we grow A. nidulans strains for live-cell imaging and how we observe the dynein-mediated distribution of early endosomes and secretory vesicles. Using an on-stage incubator and culture chambers for inverted microscopes, we can image fungal hyphae that naturally attach to the bottom of the chambers, using wide-field epifluorescence microscopes or the new Zeiss LSM 980 (with Airyscan 2) microscope. In addition to methods for preparing cells for imaging, a procedure for A. nidulans transformation is also described.
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Affiliation(s)
- Rongde Qiu
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, MD, USA
| | - Jun Zhang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, MD, USA
| | - Dennis McDaniel
- Department of Microbiology and Immunology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, MD, USA
| | - Miguel A Peñalva
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain.
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, MD, USA.
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18
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Mayya C, Naveena AH, Sinha P, Wunder C, Johannes L, Bhatia D. The roles of dynein and myosin VI motor proteins in endocytosis. J Cell Sci 2022; 135:274777. [DOI: 10.1242/jcs.259387] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
ABSTRACT
Endocytosis is indispensable for multiple cellular processes, including signalling, cell adhesion, migration, as well as the turnover of plasma membrane lipids and proteins. The dynamic interplay and regulation of different endocytic entry routes requires multiple cytoskeletal elements, especially motor proteins that bind to membranes and transport vesicles along the actin and microtubule cytoskeletons. Dynein and kinesin motor proteins transport vesicles along microtubules, whereas myosins drive vesicles along actin filaments. Here, we present a brief overview of multiple endocytic pathways and our current understanding of the involvement of these motor proteins in the regulation of the different cellular entry routes. We particularly focus on structural and mechanistic details of the retrograde motor proteins dynein and myosin VI (also known as MYO6), along with their adaptors, which have important roles in the early events of endocytosis. We conclude by highlighting the key challenges in elucidating the involvement of motor proteins in endocytosis and intracellular membrane trafficking.
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Affiliation(s)
- Chaithra Mayya
- Biological Engineering, Indian Institute of Technology Gandhinagar, Palaj, 382355 Gandhinagar, India
| | - A. Hema Naveena
- Biological Engineering, Indian Institute of Technology Gandhinagar, Palaj, 382355 Gandhinagar, India
| | - Pankhuri Sinha
- Biological Engineering, Indian Institute of Technology Gandhinagar, Palaj, 382355 Gandhinagar, India
| | - Christian Wunder
- Institut Curie, PSL Research University, U1143 INSERM, UMR3666 CNRS, Cellular and Chemical Biology Unit, 26 rue d'Ulm, 75248 Paris CEDEX 05, France
| | - Ludger Johannes
- Institut Curie, PSL Research University, U1143 INSERM, UMR3666 CNRS, Cellular and Chemical Biology Unit, 26 rue d'Ulm, 75248 Paris CEDEX 05, France
| | - Dhiraj Bhatia
- Biological Engineering, Indian Institute of Technology Gandhinagar, Palaj, 382355 Gandhinagar, India
- Center for Biomedical Engineering, Indian Institute of Technology Gandhinagar, Palaj, 382355 Gandhinagar, India
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19
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Susaimanickam PJ, Kiral FR, Park IH. Region Specific Brain Organoids to Study Neurodevelopmental Disorders. Int J Stem Cells 2022; 15:26-40. [PMID: 35220290 PMCID: PMC8889336 DOI: 10.15283/ijsc22006] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 01/17/2022] [Indexed: 12/03/2022] Open
Abstract
Region specific brain organoids are brain organoids derived by patterning protocols using extrinsic signals as opposed to cerebral organoids obtained by self-patterning. The main focus of this review is to discuss various region-specific brain organoids developed so far and their application in modeling neurodevelopmental disease. We first discuss the principles of neural axis formation by series of growth factors, such as SHH, WNT, BMP signalings, that are critical to generate various region-specific brain organoids. Then we discuss various neurodevelopmental disorders modeled so far with these region-specific brain organoids, and findings made on mechanism and treatment options for neurodevelopmental disorders (NDD).
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Affiliation(s)
- Praveen Joseph Susaimanickam
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT, USA
| | - Ferdi Ridvan Kiral
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT, USA
| | - In-Hyun Park
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT, USA
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20
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Liu W, Duan H, Zhang D, Zhang X, Luo Q, Xie T, Yan H, Peng L, Hu Y, Liang L, Zhao G, Xie Z, Hu J. Concepts and Application of DNA Origami and DNA Self-Assembly: A Systematic Review. Appl Bionics Biomech 2021; 2021:9112407. [PMID: 34824603 PMCID: PMC8610680 DOI: 10.1155/2021/9112407] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 10/20/2021] [Indexed: 01/02/2023] Open
Abstract
With the arrival of the post-Moore Era, the development of traditional silicon-based computers has reached the limit, and it is urgent to develop new computing technology to meet the needs of science and life. DNA computing has become an essential branch and research hotspot of new computer technology because of its powerful parallel computing capability and excellent data storage capability. Due to good biocompatibility and programmability properties, DNA molecules have been widely used to construct novel self-assembled structures. In this review, DNA origami is briefly introduced firstly. Then, the applications of DNA self-assembly in material physics, biogenetics, medicine, and other fields are described in detail, which will aid the development of DNA computational model in the future.
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Affiliation(s)
- Wei Liu
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
| | - Huaichuan Duan
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
| | - Derong Zhang
- School of Marxism, Chengdu Vocational & Technical College of Industry, Chengdu 610081, China
| | - Xun Zhang
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
| | - Qing Luo
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
| | - Tao Xie
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
| | - Hailian Yan
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
| | - Lianxin Peng
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
| | - Yichen Hu
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
| | - Li Liang
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
| | - Gang Zhao
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
| | - Zhenjian Xie
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
| | - Jianping Hu
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, School of Pharmacy, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610106, China
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21
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Qiu R, Zhang J, Rotty JD, Xiang X. Dynein activation in vivo is regulated by the nucleotide states of its AAA3 domain. Curr Biol 2021; 31:4486-4498.e6. [PMID: 34428469 DOI: 10.1016/j.cub.2021.07.081] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 07/05/2021] [Accepted: 07/29/2021] [Indexed: 01/02/2023]
Abstract
Cytoplasmic dynein is activated by the dynactin complex, cargo adapters and LIS1 (Lissencephaly 1). How this process is regulated in vivo remains unclear. The dynein motor ring contains six AAA+ (ATPases associated with diverse cellular activities) domains. Here, we used the filamentous fungus Aspergillus nidulans to examine whether ATP hydrolysis at AAA3 regulates dynein activation in the context of other regulators. In fungal hyphae, early endosomes undergo dynein-mediated movement away from the microtubule plus ends near the hyphal tip. Dynein normally accumulates at the microtubule plus ends. The early endosomal adaptor Hook protein, together with dynactin, drives dynein activation to cause its relocation to the microtubule minus ends. This activation process depends on LIS1, but LIS1 tends to dissociate from dynein after its activation. In this study, we found that dynein containing a mutation-blocking ATP hydrolysis at AAA3 can undergo LIS1-independent activation, consistent with our genetic data that the same mutation suppresses the growth defect of the A. nidulans LIS1-deletion mutant. Our data also suggest that blocking AAA3 ATP hydrolysis allows dynein activation by dynactin without the early endosomal adaptor. As a consequence, dynein accumulates at microtubule minus ends whereas early endosomes stay near the plus ends. Dynein containing a mutation-blocking ATP binding at AAA3 largely depends on LIS1 for activation, but this mutation abnormally prevents LIS1 dissociation upon dynein activation. Together, our data suggest that the AAA3 ATPase cycle regulates the coordination between dynein activation and cargo binding as well as the dynamic dynein-LIS1 interaction.
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Affiliation(s)
- Rongde Qiu
- Department of Biochemistry and Molecular Biology, the Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, MD 20814, USA
| | - Jun Zhang
- Department of Biochemistry and Molecular Biology, the Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, MD 20814, USA
| | - Jeremy D Rotty
- Department of Biochemistry and Molecular Biology, the Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, MD 20814, USA
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, the Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, MD 20814, USA.
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22
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Tracking Fungal Growth: Establishment of Arp1 as a Marker for Polarity Establishment and Active Hyphal Growth in Filamentous Ascomycetes. J Fungi (Basel) 2021; 7:jof7070580. [PMID: 34356959 PMCID: PMC8304394 DOI: 10.3390/jof7070580] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 07/16/2021] [Accepted: 07/18/2021] [Indexed: 12/20/2022] Open
Abstract
Polar growth is a key characteristic of all filamentous fungi. It allows these eukaryotes to not only effectively explore organic matter but also interact within its own colony, mating partners, and hosts. Therefore, a detailed understanding of the dynamics in polar growth establishment and maintenance is crucial for several fields of fungal research. We developed a new marker protein, the actin-related protein 1 (Arp1) fused to red and green fluorescent proteins, which allows for the tracking of polar axis establishment and active hyphal growth in microscopy approaches. To exclude a probable redundancy with known polarity markers, we compared the localizations of the Spitzenkörper (SPK) and Arp1 using an FM4-64 staining approach. As we show in applications with the coprophilous fungus Sordaria macrospora and the hemibiotrophic plant pathogen Colletotrichum graminicola, the monitoring of Arp1 can be used for detailed studies of hyphal growth dynamics and ascospore germination, the interpretation of chemotropic growth processes, and the tracking of elongating penetration pegs into plant material. Since the Arp1 marker showed the same dynamics in both fungi tested, we believe this marker can be broadly applied in fungal research to study the manifold polar growth processes determining fungal life.
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23
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[Effect of dexamethasone on the expression of Dynein heavy chain and Dynactin in the cytoplasm of fetal rat cerebral cortical neurons cultured in vitro]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2021; 23. [PMID: 34130788 PMCID: PMC8213999 DOI: 10.7499/j.issn.1008-8830.2103151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
OBJECTIVE To study the effect of dexamethasone (DEX) on the expression of Dynein heavy chain (DHC) and Dynactin in the cytoplasm of fetal rat cerebral cortical neurons cultured in vitro. METHODS Primary cerebral cortical neurons of fetal rats were cultured in vitro and were used to establish a cellular model of DEX intervention. According to the final concentration of DEX, the neurons were divided into three groups:control (without DEX), 0.1 μmol/L DEX, and 1.0 μmol/L DEX. On days 1, 3, and 7 after intervention, the quantitative PCR was used to observe the effect of DEX on the mRNA expression of DHC and Dynactin. The Western blot was used to observe the effect of DEX on the protein expression of DHC and Dynactin. RESULTS There was no significant difference in the mRNA expression levels of DHC and Dynactin among the three groups at all time points (P > 0.05). On day 7 after DEX intervention, the protein expression of DHC in the 1.0 μmol/L DEX group gradually increased and reached the peak over time, which was significantly higher than that in the control and 0.1 μmol/L DEX groups (P < 0.05). The control and 0.1 μmol/L DEX groups had a significant increase in the protein expression of Dynactin from day 1 to days 3 and 7 after DEX intervention (P < 0.05). The control group had a significant increase in the protein expression of Dynactin from day 3 to day 7 after intervention (P < 0.05), while the 0.1 μmol/L DEX group had a significant reduction in the protein expression of Dynactin from day 3 to day 7 after intervention (P < 0.05). On days 3 and 7 after DEX intervention, the 0.1 μmol/L DEX and 1.0 μmol/L DEX groups had a significantly lower protein expression level of Dynactin in the cerebral cortical neurons than the control group (P < 0.05). On day 7 after DEX intervention, the 1.0 μmol/L DEX group had a significantly lower protein expression level of Dynactin than the 0.1 μmol/L DEX group (P < 0.05). CONCLUSIONS DEX affects the protein expression of DHC and Dynactin in the fetal rat cerebral cortical neurons cultured in vitro, possibly in a concentration- and time-dependent manner.
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Pinar M, Peñalva MA. The fungal RABOME: RAB GTPases acting in the endocytic and exocytic pathways of Aspergillus nidulans (with excursions to other filamentous fungi). Mol Microbiol 2021; 116:53-70. [PMID: 33724562 DOI: 10.1111/mmi.14716] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 03/04/2021] [Accepted: 03/11/2021] [Indexed: 10/21/2022]
Abstract
RAB GTPases are major determinants of membrane identity that have been exploited as highly specific reporters to study intracellular traffic in vivo. A score of fungal papers have considered individual RABs, but systematic, integrated studies on the localization and physiological role of these regulators and their effectors have been performed only with Aspergillus nidulans. These studies have influenced the intracellular trafficking field beyond fungal specialists, leading to findings such as the maturation of trans-Golgi (TGN) cisternae into post-Golgi RAB11 secretory vesicles, the concept that these RAB11 secretory carriers are loaded with three molecular nanomotors, the understanding of the role of endocytic recycling mediated by RAB6 and RAB11 in determining the hyphal mode of life, the discovery that early endosome maturation and the ESCRT pathway are essential, the identification of specific adaptors of dynein-dynactin to RAB5 endosomes, the exquisite dependence that autophagy displays on RAB1 activity, the role of TRAPPII as a GEF for RAB11, or the conclusion that the RAB1-to-RAB11 transition is not mediated by TRAPP maturation. A remarkable finding was that the A. nidulans Spitzenkörper contains four RABs: RAB11, Sec4, RAB6, and RAB1. How these RABs cooperate during exocytosis represents an as yet outstanding question.
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Affiliation(s)
- Mario Pinar
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain
| | - Miguel A Peñalva
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain
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25
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Jackson T, Belsham GJ. Picornaviruses: A View from 3A. Viruses 2021; 13:v13030456. [PMID: 33799649 PMCID: PMC7999760 DOI: 10.3390/v13030456] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/08/2021] [Accepted: 03/09/2021] [Indexed: 12/14/2022] Open
Abstract
Picornaviruses are comprised of a positive-sense RNA genome surrounded by a protein shell (or capsid). They are ubiquitous in vertebrates and cause a wide range of important human and animal diseases. The genome encodes a single large polyprotein that is processed to structural (capsid) and non-structural proteins. The non-structural proteins have key functions within the viral replication complex. Some, such as 3Dpol (the RNA dependent RNA polymerase) have conserved functions and participate directly in replicating the viral genome, whereas others, such as 3A, have accessory roles. The 3A proteins are highly divergent across the Picornaviridae and have specific roles both within and outside of the replication complex, which differ between the different genera. These roles include subverting host proteins to generate replication organelles and inhibition of cellular functions (such as protein secretion) to influence virus replication efficiency and the host response to infection. In addition, 3A proteins are associated with the determination of host range. However, recent observations have challenged some of the roles assigned to 3A and suggest that other viral proteins may carry them out. In this review, we revisit the roles of 3A in the picornavirus life cycle. The 3AB precursor and mature 3A have distinct functions during viral replication and, therefore, we have also included discussion of some of the roles assigned to 3AB.
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Affiliation(s)
- Terry Jackson
- The Pirbright Institute, Pirbright, Woking, Surrey GU24 0NF, UK;
| | - Graham J. Belsham
- Department of Veterinary and Animal Sciences, University of Copenhagen, 1870 Frederiksberg, Denmark
- Correspondence:
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26
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Hou W, Kang W, Li Y, Shan Y, Wang S, Liu F. Dynamic Dissection of Dynein and Kinesin-1 Cooperatively Mediated Intercellular Transport of Porcine Epidemic Diarrhea Coronavirus along Microtubule Using Single Virus Tracking. Virulence 2021; 12:615-629. [PMID: 33538234 PMCID: PMC7872075 DOI: 10.1080/21505594.2021.1878748] [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] [Indexed: 02/06/2023] Open
Abstract
It is now clear that the intercellular transport on microtubules by dynein and kinesin-1 motors has an important role in the replication and spread of many viruses. Porcine epidemic diarrhea virus (PEDV) is an enveloped, single-stranded RNA virus of the Coronavirus family, which can infect swine of all ages and cause severe economic losses in the swine industry. Elucidating the molecular mechanisms of the intercellular transport of PEDV through microtubule, dynein and kinesin-1 will be crucial for understanding its pathogenesis. Here, we demonstrate that microtubule, dynein, and kinesin-1 are involved in PEDV infection and can influence PEDV fusion and accumulation in the perinuclear region but cannot affect PEDV attachment or internalization. Furthermore, we adopted a single-virus tracking technique to dynamically observe PEDV intracellular transport with five different types: unidirectional movement toward microtubule plus ends; unidirectional movement toward microtubule minus ends; bidirectional movement along the same microtubule; bidirectional movement along different microtubules and motionless state. Among these types, the functions of dynein and kinesin-1 in PEDV intercellular transport were further analyzed by single-virus tracking and found that dynein and kinesin-1 mainly transport PEDV to the minus and plus ends of the microtubules, respectively; meanwhile, they also can transport PEDV to the opposite ends of the microtubules different from their conventional transport directions and also coordinate the bidirectional movement of PEDV along the same or different microtubules through their cooperation. These results provided deep insights and references to understand the pathogenesis of PEDV as well as to develop vaccines and treatments.
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Affiliation(s)
- Wei Hou
- Joint International Research Laboratory of Animal Health and Food Safety of Ministry of Education & Single Molecule Nanometry Laboratory (Sinmolab), Nanjing Agricultural University , Nanjing, Jiangsu, China
| | - Wenjie Kang
- Joint International Research Laboratory of Animal Health and Food Safety of Ministry of Education & Single Molecule Nanometry Laboratory (Sinmolab), Nanjing Agricultural University , Nanjing, Jiangsu, China
| | - Yangyang Li
- Joint International Research Laboratory of Animal Health and Food Safety of Ministry of Education & Single Molecule Nanometry Laboratory (Sinmolab), Nanjing Agricultural University , Nanjing, Jiangsu, China
| | - Yanke Shan
- Joint International Research Laboratory of Animal Health and Food Safety of Ministry of Education & Single Molecule Nanometry Laboratory (Sinmolab), Nanjing Agricultural University , Nanjing, Jiangsu, China
| | - Shouyu Wang
- Joint International Research Laboratory of Animal Health and Food Safety of Ministry of Education & Single Molecule Nanometry Laboratory (Sinmolab), Nanjing Agricultural University , Nanjing, Jiangsu, China.,Computational Optics Laboratory, Jiangnan University , Wuxi, Jiangsu, China
| | - Fei Liu
- Joint International Research Laboratory of Animal Health and Food Safety of Ministry of Education & Single Molecule Nanometry Laboratory (Sinmolab), Nanjing Agricultural University , Nanjing, Jiangsu, China
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27
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Salogiannis J, Christensen JR, Songster LD, Aguilar-Maldonado A, Shukla N, Reck-Peterson SL. PxdA interacts with the DipA phosphatase to regulate peroxisome hitchhiking on early endosomes. Mol Biol Cell 2021; 32:492-503. [PMID: 33476181 PMCID: PMC8101442 DOI: 10.1091/mbc.e20-08-0559] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
In canonical microtubule-based transport, adaptor proteins link cargoes to dynein and kinesin motors. Recently, an alternative mode of transport known as “hitchhiking” was discovered, where cargoes achieve motility by hitching a ride on already-motile cargoes, rather than attaching to a motor protein. Hitchhiking has been best studied in two filamentous fungi, Aspergillus nidulans and Ustilago maydis. In U. maydis, ribonucleoprotein complexes, peroxisomes, lipid droplets (LDs), and endoplasmic reticulum hitchhike on early endosomes (EEs). In A. nidulans, peroxisomes hitchhike using a putative molecular linker, peroxisome distribution mutant A (PxdA), which associates with EEs. However, whether other organelles use PxdA to hitchhike on EEs is unclear, as are the molecular mechanisms that regulate hitchhiking. Here we find that the proper distribution of LDs, mitochondria, and preautophagosomes do not require PxdA, suggesting that PxdA is a peroxisome-specific molecular linker. We identify two new pxdA alleles, including a point mutation (R2044P) that disrupts PxdA’s ability to associate with EEs and reduces peroxisome movement. We also identify a novel regulator of peroxisome hitchhiking, the phosphatase DipA. DipA colocalizes with EEs and its association with EEs relies on PxdA. Together, our data suggest that PxdA and the DipA phosphatase are specific regulators of peroxisome hitchhiking on EEs.
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Affiliation(s)
- John Salogiannis
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Howard Hughes Medical Institute, Chevy Chase, MD 20815
| | - Jenna R Christensen
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Livia D Songster
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Division of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, CA 92093
| | - Adriana Aguilar-Maldonado
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Nandini Shukla
- The Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 043210.,Department of Molecular Genetics, The Ohio State University, Columbus, OH 043210
| | - Samara L Reck-Peterson
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Division of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, CA 92093.,Howard Hughes Medical Institute, Chevy Chase, MD 20815
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28
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Covill-Cooke C, Toncheva VS, Kittler JT. Regulation of peroxisomal trafficking and distribution. Cell Mol Life Sci 2020; 78:1929-1941. [PMID: 33141311 PMCID: PMC7966214 DOI: 10.1007/s00018-020-03687-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/02/2020] [Accepted: 10/19/2020] [Indexed: 12/18/2022]
Abstract
Peroxisomes are organelles that perform a wide range of essential metabolic processes. To ensure that peroxisomes are optimally positioned in the cell, they must be transported by both long- and short-range trafficking events in response to cellular needs. Here, we review our current understanding of the mechanisms by which the cytoskeleton and organelle contact sites alter peroxisomal distribution. Though the focus of the review is peroxisomal transport in mammalian cells, findings from flies and fungi are used for comparison and to inform the gaps in our understanding. Attention is given to the apparent overlap in regulatory mechanisms for mitochondrial and peroxisomal trafficking, along with the recently discovered role of the mitochondrial Rho-GTPases, Miro, in peroxisomal dynamics. Moreover, we outline and discuss the known pathological and pharmacological conditions that perturb peroxisomal positioning. We conclude by highlighting several gaps in our current knowledge and suggest future directions that require attention.
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Affiliation(s)
| | - Viktoriya S Toncheva
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, WC1E 6BT, UK
| | - Josef T Kittler
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, WC1E 6BT, UK.
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29
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Fourel G, Boscheron C. Tubulin mutations in neurodevelopmental disorders as a tool to decipher microtubule function. FEBS Lett 2020; 594:3409-3438. [PMID: 33064843 DOI: 10.1002/1873-3468.13958] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 09/28/2020] [Accepted: 10/05/2020] [Indexed: 01/08/2023]
Abstract
Malformations of cortical development (MCDs) are a group of severe brain malformations associated with intellectual disability and refractory childhood epilepsy. Human missense heterozygous mutations in the 9 α-tubulin and 10 β-tubulin isoforms forming the heterodimers that assemble into microtubules (MTs) were found to cause MCDs. However, how a single mutated residue in a given tubulin isoform can perturb the entire microtubule population in a neuronal cell remains a crucial question. Here, we examined 85 MCD-associated tubulin mutations occurring in TUBA1A, TUBB2, and TUBB3 and their location in a three-dimensional (3D) microtubule cylinder. Mutations hitting residues exposed on the outer microtubule surface are likely to alter microtubule association with partners, while alteration of intradimer contacts may impair dimer stability and straightness. Other types of mutations are predicted to alter interdimer and lateral contacts, which are responsible for microtubule cohesion, rigidity, and dynamics. MCD-associated tubulin mutations surprisingly fall into all categories, thus providing unexpected insights into how a single mutation may impair microtubule function and elicit dominant effects in neurons.
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30
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Xiang X, Qiu R. Cargo-Mediated Activation of Cytoplasmic Dynein in vivo. Front Cell Dev Biol 2020; 8:598952. [PMID: 33195284 PMCID: PMC7649786 DOI: 10.3389/fcell.2020.598952] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 10/07/2020] [Indexed: 12/12/2022] Open
Abstract
Cytoplasmic dynein-1 is a minus-end-directed microtubule motor that transports a variety of cargoes including early endosomes, late endosomes and other organelles. In many cell types, dynein accumulates at the microtubule plus end, where it interacts with its cargo to be moved toward the minus end. Dynein binds to its various cargoes via the dynactin complex and specific cargo adapters. Dynactin and some of the coiled-coil-domain-containing cargo adapters not only link dynein to cargo but also activate dynein motility, which implies that dynein is activated by its cellular cargo. Structural studies indicate that a dynein dimer switches between the autoinhibited phi state and an open state; and the binding of dynactin and a cargo adapter to the dynein tails causes the dynein motor domains to have a parallel configuration, allowing dynein to walk processively along a microtubule. Recently, the dynein regulator LIS1 has been shown to be required for dynein activation in vivo, and its mechanism of action involves preventing dynein from switching back to the autoinhibited state. In this review, we will discuss our current understanding of dynein activation and point out the gaps of knowledge on the spatial regulation of dynein in live cells. In addition, we will emphasize the importance of studying a complete set of dynein regulators for a better understanding of dynein regulation in vivo.
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Affiliation(s)
- Xin Xiang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences - F. Edward Hébert School of Medicine, Bethesda, MD, United States
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31
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Yamamoto KA, Blackburn K, Migowski E, Goshe MB, Brown DT, Ferreira DF, Soares MR. Quantitative proteomic analysis of the tizoxanide effect in vero cells. Sci Rep 2020; 10:14733. [PMID: 32895447 PMCID: PMC7477200 DOI: 10.1038/s41598-020-71634-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 07/27/2020] [Indexed: 12/17/2022] Open
Abstract
Nitazoxanide (NTZ) is effective against helminths and numerous microorganisms, including bacteria and viruses. In vivo, NTZ is metabolized into Tizoxanide (TIZ), which is the active circulating metabolite. With the emergence of SARS-Cov-2 as a Pandemic agent, NTZ became one of the molecules already approved for human use to engage clinical trials, due to results in vitro showing that NTZ was highly effective against the SARS-Cov-2, agent of COVID-19. There are currently several ongoing clinical trials mainly in the USA and Brazil involving NTZ due not only to the in vitro results, but also for its long-known safety. Here, we study the response of Vero cells to TIZ treatment and unveil possible mechanisms for its antimicrobial effect, using a label-free proteomic approach (LC/MS/MS) analysis to compare the proteomic profile between untreated- and TIZ-treated cells. Fifteen differentially expressed proteins were observed related to various biological processes, including translation, intracellular trafficking, RNA processing and modification, and signal transduction. The broad antimicrobial range of TIZ points towards its overall effect in lowering cell metabolism and RNA processing and modification. The decreased levels of FASN, HNRNPH and HNRNPK with the treatment appear to be important for antiviral activity.
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Affiliation(s)
- K A Yamamoto
- Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Caixa Postal 68563, Rio de Janeiro, RJ, 21941-909, Brazil
| | - K Blackburn
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, USA
| | - E Migowski
- Institute of Pediatrics and Puericulture Martagão Gesteira, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - M B Goshe
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, USA
| | - D T Brown
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, USA
| | - D F Ferreira
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, USA.,Department of Virology, Paulo de Góes Microbiology Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - M R Soares
- Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Caixa Postal 68563, Rio de Janeiro, RJ, 21941-909, Brazil.
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32
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Rogers AM, Egan MJ. Autophagy machinery promotes the chaperone-mediated formation and compartmentalization of protein aggregates during appressorium development by the rice blast fungus. Mol Biol Cell 2020; 31:2298-2305. [PMID: 32816646 PMCID: PMC7851963 DOI: 10.1091/mbc.e20-01-0068] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The chaperone-mediated sequestration of misfolded proteins into specialized quality control compartments represents an important strategy for maintaining protein homeostasis in response to stress. However, precisely how this process is controlled in time and subcellular space and integrated with the cell's protein refolding and degradation pathways remains unclear. We set out to understand how aggregated proteins are managed during infection-related development by a globally devastating plant pathogenic fungus and to determine how impaired protein quality control impacts cellular differentiation and pathogenesis in this system. Here we show that in the absence of Hsp104 disaggregase activity, aggregated proteins are spatially sequestered into quality control compartments within conidia, but not within terminally differentiated infection cells, and thus spatial protein quality control is cell type–dependent. We demonstrate that impaired aggregate resolution results in a short-term developmental penalty but has no significant impact upon appressorium function. Finally, we show that, somewhat unexpectedly, the autophagy machinery is necessary for the normal formation and compartmentalization of protein aggregates. Taken together, our findings provide important new insight into spatial protein quality control during the process of terminal cellular differentiation by a globally important model eukaryote and reveal a new level of interplay between major proteostasis pathways.
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Affiliation(s)
- Audra Mae Rogers
- Department of Entomology and Plant Pathology, Division of Agriculture, University of Arkansas Systems, Fayetteville, AR 72701
| | - Martin John Egan
- Department of Entomology and Plant Pathology, Division of Agriculture, University of Arkansas Systems, Fayetteville, AR 72701.,Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701
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33
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Markus SM, Marzo MG, McKenney RJ. New insights into the mechanism of dynein motor regulation by lissencephaly-1. eLife 2020; 9:59737. [PMID: 32692650 PMCID: PMC7373426 DOI: 10.7554/elife.59737] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 07/13/2020] [Indexed: 12/20/2022] Open
Abstract
Lissencephaly (‘smooth brain’) is a severe brain disease associated with numerous symptoms, including cognitive impairment, and shortened lifespan. The main causative gene of this disease – lissencephaly-1 (LIS1) – has been a focus of intense scrutiny since its first identification almost 30 years ago. LIS1 is a critical regulator of the microtubule motor cytoplasmic dynein, which transports numerous cargoes throughout the cell, and is a key effector of nuclear and neuronal transport during brain development. Here, we review the role of LIS1 in cellular dynein function and discuss recent key findings that have revealed a new mechanism by which this molecule influences dynein-mediated transport. In addition to reconciling prior observations with this new model for LIS1 function, we also discuss phylogenetic data that suggest that LIS1 may have coevolved with an autoinhibitory mode of cytoplasmic dynein regulation.
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Affiliation(s)
- Steven M Markus
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, United States
| | - Matthew G Marzo
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, United States
| | - Richard J McKenney
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, United States
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34
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Bieger BD, Rogers AM, Bates S, Egan MJ. Long-distance early endosome motility in Aspergillus fumigatus promotes normal hyphal growth behaviors in controlled microenvironments but is dispensable for virulence. Traffic 2020; 21:479-487. [PMID: 32378777 DOI: 10.1111/tra.12735] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 05/01/2020] [Accepted: 05/04/2020] [Indexed: 12/13/2022]
Abstract
In filamentous fungi, early endosomes are continuously trafficked to, and from, the growing hyphal tip by microtubule-based motor proteins, serving as platforms for the long-distance transport of diverse cargos including mRNA, signaling molecules, and other organelles which hitchhike on them. While the cellular machinery for early endosome motility in filamentous fungi is fairly well characterized, the broader physiological significance of this process remains less well understood. We set out to determine the importance of long-distance early endosome trafficking in Aspergillus fumigatus, an opportunistic human pathogenic fungus that can cause devastating pulmonary infections in immunocompromised individuals. We first characterized normal early endosome motile behavior in A. fumigatus, then generated a mutant in which early endosome motility is severely perturbed through targeted deletion of the gene encoding for FtsA, one of a complex of proteins that links early endosomes to their motor proteins. Using a microfluidics-based approach we show that contact-induced hyphal branching behaviors are impaired in ΔftsA mutants, but that FtsA-mediated early endosome motility is dispensable for virulence in an invertebrate infection model. Overall, our study provides new insight into early endosome motility in an important human pathogenic fungus.
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Affiliation(s)
- Baronger Dowell Bieger
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, Arkansas, USA.,Cell and Molecular Biology Program, University of Arkansas, Fayetteville, Arkansas, USA
| | - Audra Mae Rogers
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, Arkansas, USA
| | - Steven Bates
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Exeter, UK
| | - Martin John Egan
- Department of Entomology and Plant Pathology, University of Arkansas Systems Division of Agriculture, Fayetteville, Arkansas, USA.,Cell and Molecular Biology Program, University of Arkansas, Fayetteville, Arkansas, USA
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35
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Canty JT, Yildiz A. Activation and Regulation of Cytoplasmic Dynein. Trends Biochem Sci 2020; 45:440-453. [PMID: 32311337 PMCID: PMC7179903 DOI: 10.1016/j.tibs.2020.02.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 01/30/2020] [Accepted: 02/04/2020] [Indexed: 12/30/2022]
Abstract
Cytoplasmic dynein is an AAA+ motor that drives the transport of many intracellular cargoes towards the minus end of microtubules (MTs). Previous in vitro studies characterized isolated dynein as an exceptionally weak motor that moves slowly and diffuses on an MT. Recent studies altered this view by demonstrating that dynein remains in an autoinhibited conformation on its own, and processive motility is activated when it forms a ternary complex with dynactin and a cargo adaptor. This complex assembles more efficiently in the presence of Lis1, providing an explanation for why Lis1 is a required cofactor for most cytoplasmic dynein-driven processes in cells. This review describes how dynein motility is activated and regulated by cargo adaptors and accessory proteins.
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Affiliation(s)
- John T Canty
- Biophysics Graduate Group, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Ahmet Yildiz
- Biophysics Graduate Group, University of California at Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cellular Biology, University of California at Berkeley, Berkeley, CA 94720, USA; Physics Department, University of California at Berkeley, Berkeley, CA 94720, USA.
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36
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Htet ZM, Gillies JP, Baker RW, Leschziner AE, DeSantis ME, Reck-Peterson SL. LIS1 promotes the formation of activated cytoplasmic dynein-1 complexes. Nat Cell Biol 2020; 22:518-525. [PMID: 32341549 PMCID: PMC7271980 DOI: 10.1038/s41556-020-0506-z] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 03/11/2020] [Indexed: 12/30/2022]
Abstract
Cytoplasmic dynein-1 is a molecular motor that drives nearly all minus-end-directed microtubule-based transport in human cells, performing functions that range from retrograde axonal transport to mitotic spindle assembly1,2. Activated dynein complexes consist of one or two dynein dimers, the dynactin complex and an 'activating adaptor', and they show faster velocity when two dynein dimers are present3-6. Little is known about the assembly process of this massive ~4 MDa complex. Here, using purified recombinant human proteins, we uncover a role for the dynein-binding protein LIS1 in promoting the formation of activated dynein-dynactin complexes that contain two dynein dimers. Complexes activated by proteins representing three families of activating adaptors-BicD2, Hook3 and Ninl-all show enhanced motile properties in the presence of LIS1. Activated dynein complexes do not require sustained LIS1 binding for fast velocity. Using cryo-electron microscopy, we show that human LIS1 binds to dynein at two sites on the motor domain of dynein. Our research suggests that LIS1 binding at these sites functions in multiple stages of assembling the motile dynein-dynactin-activating adaptor complex.
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Affiliation(s)
- Zaw Min Htet
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
- Biophysics Graduate Program, Harvard Medical School, Boston, MA, USA
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, USA
| | - John P Gillies
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA, USA
| | - Richard W Baker
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC, USA
| | - Andres E Leschziner
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
- Division of Biological Sciences, Molecular Biology Section, University of California San Diego, La Jolla, CA, USA
| | - Morgan E DeSantis
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA.
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
| | - Samara L Reck-Peterson
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA.
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, La Jolla, CA, USA.
- Howard Hughes Medical Institute, Chevy Chase, MD, USA.
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37
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Lis1 activates dynein motility by modulating its pairing with dynactin. Nat Cell Biol 2020; 22:570-578. [PMID: 32341547 PMCID: PMC7212015 DOI: 10.1038/s41556-020-0501-4] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 03/03/2020] [Indexed: 12/18/2022]
Abstract
Lissencephaly-1 (Lis1) is a key cofactor for dynein-mediated intracellular transport towards the minus-ends of microtubules. It remains unclear whether Lis1 serves as an inhibitor or an activator of mammalian dynein motility. Here we use single-molecule imaging and optical trapping to show that Lis1 does not directly alter the stepping and force production of individual dynein motors assembled with dynactin and a cargo adaptor. Instead, Lis1 promotes the formation of an active complex with dynactin. Lis1 also favours the recruitment of two dyneins to dynactin, resulting in increased velocity, higher force production and more effective competition against kinesin in a tug-of-war. Lis1 dissociates from motile complexes, indicating that its primary role is to orchestrate the assembly of the transport machinery. We propose that Lis1 binding releases dynein from its autoinhibited state, which provides a mechanistic explanation for why Lis1 is required for efficient transport of many dynein-associated cargos in cells.
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38
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Tempes A, Weslawski J, Brzozowska A, Jaworski J. Role of dynein-dynactin complex, kinesins, motor adaptors, and their phosphorylation in dendritogenesis. J Neurochem 2020; 155:10-28. [PMID: 32196676 DOI: 10.1111/jnc.15010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 02/24/2020] [Accepted: 03/13/2020] [Indexed: 12/21/2022]
Abstract
One of the characteristic features of different classes of neurons that is vital for their proper functioning within neuronal networks is the shape of their dendritic arbors. To properly develop dendritic trees, neurons need to accurately control the intracellular transport of various cellular cargo (e.g., mRNA, proteins, and organelles). Microtubules and motor proteins (e.g., dynein and kinesins) that move along microtubule tracks play an essential role in cargo sorting and transport to the most distal ends of neurons. Equally important are motor adaptors, which may affect motor activity and specify cargo that is transported by the motor. Such transport undergoes very dynamic fine-tuning in response to changes in the extracellular environment and synaptic transmission. Such regulation is achieved by the phosphorylation of motors, motor adaptors, and cargo, among other mechanisms. This review focuses on the contribution of the dynein-dynactin complex, kinesins, their adaptors, and the phosphorylation of these proteins in the formation of dendritic trees by maturing neurons. We primarily review the effects of the motor activity of these proteins in dendrites on dendritogenesis. We also discuss less anticipated mechanisms that contribute to dendrite growth, such as dynein-driven axonal transport and non-motor functions of kinesins.
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Affiliation(s)
- Aleksandra Tempes
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Jan Weslawski
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Agnieszka Brzozowska
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Jacek Jaworski
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
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Qiu R, Zhang J, Xiang X. The splicing-factor Prp40 affects dynein-dynactin function in Aspergillus nidulans. Mol Biol Cell 2020; 31:1289-1301. [PMID: 32267207 PMCID: PMC7353152 DOI: 10.1091/mbc.e20-03-0166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The multi-component cytoplasmic dynein transports cellular cargoes with the help of another multi-component complex dynactin, but we do not know enough about factors that may affect the assembly and functions of these proteins. From a genetic screen for mutations affecting early-endosome distribution in Aspergillus nidulans, we identified the prp40AL438* mutation in Prp40A, a homologue of Prp40, an essential RNA-splicing factor in the budding yeast. Prp40A is not essential for splicing, although it associates with the nuclear splicing machinery. The prp40AL438* mutant is much healthier than the ∆prp40A mutant, but both mutants exhibit similar defects in dynein-mediated early-endosome transport and nuclear distribution. In the prp40AL438* mutant, the frequency but not the speed of dynein-mediated early-endosome transport is decreased, which correlates with a decrease in the microtubule plus-end accumulations of dynein and dynactin. Within the dynactin complex, the actin-related protein Arp1 forms a mini-filament. In a pull-down assay, the amount of Arp1 pulled down with its pointed-end protein Arp11 is lowered in the prp40AL438* mutant. In addition, we found from published interactome data that a mammalian Prp40 homologue PRPF40A interacts with Arp1. Thus, Prp40 homologues may regulate the assembly or function of dynein–dynactin and their mechanisms deserve to be further studied.
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Affiliation(s)
- Rongde Qiu
- Department of Biochemistry and Molecular Biology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814
| | - Jun Zhang
- Department of Biochemistry and Molecular Biology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814
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40
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Minor MM, Hollinger FB, McNees AL, Jung SY, Jain A, Hyser JM, Bissig KD, Slagle BL. Hepatitis B Virus HBx Protein Mediates the Degradation of Host Restriction Factors through the Cullin 4 DDB1 E3 Ubiquitin Ligase Complex. Cells 2020; 9:E834. [PMID: 32235678 PMCID: PMC7226812 DOI: 10.3390/cells9040834] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 03/24/2020] [Accepted: 03/25/2020] [Indexed: 02/06/2023] Open
Abstract
The hepatitis B virus (HBV) regulatory HBx protein is required for infection, and its binding to cellular damaged DNA binding protein 1 (DDB1) is critical for this function. DDB1 is an adaptor protein for the cullin 4A Really Interesting New Gene (RING) E3 ubiquitin ligase (CRL4) complex and functions by binding cellular DDB1 cullin associated factor (DCAF) receptor proteins that recruit substrates for ubiquitination and degradation. We compared the proteins found in the CRL4 complex immunoprecipitated from uninfected versus HBV-infected hepatocytes from human liver chimeric mice for insight into mechanisms by which HBV and the cell interact within the CRL4 complex. Consistent with its role as a viral DCAF, HBx was found in the HBV CRL4 complexes. In tissue culture transfection experiments, we showed that HBx expression led to decreased levels of known restriction factor structural maintenance of chromosomes protein 6 (SMC6) and putative restriction factors stromal interaction molecule 1 (STIM1, zinc finger E-box binding homeobox 2 (ZEB2), and proteasome activator subunit 4 (PSME4). Moreover, silencing of these proteins led to increased HBV replication in the HepG2-sodium taurocholate cotransporting polypeptide (NTCP) infection model. We also identified cellular DCAF receptors in CRL4 complexes from humanized mice. Increasing amounts of HBx did not reveal competitive DCAF binding to cullin4 (CUL4)-DDB1 in plasmid-transfected cells. Our results suggest a model in which HBx benefits virus replication by directly or indirectly degrading multiple cellular restriction factors.
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Affiliation(s)
- Marissa M. Minor
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA; (M.M.M.); (F.B.H.); (A.L.M.); (J.M.H.)
| | - F. Blaine Hollinger
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA; (M.M.M.); (F.B.H.); (A.L.M.); (J.M.H.)
| | - Adrienne L. McNees
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA; (M.M.M.); (F.B.H.); (A.L.M.); (J.M.H.)
- Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX 77030, USA;
| | - Sung Yun Jung
- Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX 77030, USA;
- Department of Biochemistry, Baylor College of Medicine, Houston, TX 77030, USA
| | - Antrix Jain
- Mass Spectrometry Proteomics Core, Baylor College of Medicine, Houston, TX 77030, USA;
| | - Joseph M. Hyser
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA; (M.M.M.); (F.B.H.); (A.L.M.); (J.M.H.)
| | - Karl-Dimiter Bissig
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, TX 77030, USA;
| | - Betty L. Slagle
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA; (M.M.M.); (F.B.H.); (A.L.M.); (J.M.H.)
- Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX 77030, USA;
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41
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Qiu R, Zhang J, Xiang X. LIS1 regulates cargo-adapter-mediated activation of dynein by overcoming its autoinhibition in vivo. J Cell Biol 2019; 218:3630-3646. [PMID: 31562232 PMCID: PMC6829669 DOI: 10.1083/jcb.201905178] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 08/08/2019] [Accepted: 08/29/2019] [Indexed: 02/08/2023] Open
Abstract
Deficiency of the LIS1 protein causes lissencephaly, a brain developmental disorder. Although LIS1 binds the microtubule motor cytoplasmic dynein and has been linked to dynein function in many experimental systems, its mechanism of action remains unclear. Here, we revealed its function in cargo-adapter-mediated dynein activation in the model organism Aspergillus nidulans Specifically, we found that overexpressed cargo adapter HookA (Hook in A. nidulans) missing its cargo-binding domain (ΔC-HookA) causes dynein and its regulator dynactin to relocate from the microtubule plus ends to the minus ends, and this relocation requires LIS1 and its binding protein, NudE. Astonishingly, the requirement for LIS1 or NudE can be bypassed to a significant extent by mutations that prohibit dynein from forming an autoinhibited conformation in which the motor domains of the dynein dimer are held close together. Our results suggest a novel mechanism of LIS1 action that promotes the switch of dynein from the autoinhibited state to an open state to facilitate dynein activation.
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Affiliation(s)
- Rongde Qiu
- Department of Biochemistry and Molecular Biology, the Uniformed Services University F. Edward Hébert School of Medicine, Bethesda, MD
| | - Jun Zhang
- Department of Biochemistry and Molecular Biology, the Uniformed Services University F. Edward Hébert School of Medicine, Bethesda, MD
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, the Uniformed Services University F. Edward Hébert School of Medicine, Bethesda, MD
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42
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Liu L, Lu J, Li X, Wu A, Wu Q, Zhao M, Tang N, Song H. The LIS1/NDE1 Complex Is Essential for FGF Signaling by Regulating FGF Receptor Intracellular Trafficking. Cell Rep 2019; 22:3277-3291. [PMID: 29562183 DOI: 10.1016/j.celrep.2018.02.077] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 01/23/2018] [Accepted: 02/21/2018] [Indexed: 11/27/2022] Open
Abstract
Intracellular transport of membranous organelles and protein complexes to various destinations is fundamental to signaling transduction and cellular function. The cytoplasmic dynein motor and its regulatory proteins LIS1 and NDE1 are required for transporting a variety of cellular cargos along the microtubule network. In this study, we show that deletion of Lis1 in developing lung endoderm and limb mesenchymal cells causes agenesis of the lungs and limbs. In both mutants, there is increased cell death and decreased fibroblast growth factor (FGF) signaling activity. Mechanistically, LIS1 and its interacting protein NDE1/NDEL1 are associated with FGF receptor-containing vesicles and regulate FGF receptor intracellular trafficking and degradation. Notably, FGF signaling promotes NDE1 tyrosine phosphorylation, which leads to dissociation of LIS1/NDE1 complex. Thus, our studies identify the LIS1/NDE1 complex as an important FGF signaling regulator and provide insights into the bidirectional regulation of cell signaling and transport machinery for endocytosis.
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Affiliation(s)
- Liansheng Liu
- Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou 310058, China
| | - Jinqiu Lu
- Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou 310058, China
| | - Xiaoling Li
- Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou 310058, China
| | - Ailing Wu
- Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou 310058, China
| | - Qingzhe Wu
- Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou 310058, China
| | - Mujun Zhao
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Nan Tang
- National Institute of Biological Sciences, Beijing 102206, China
| | - Hai Song
- Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou 310058, China.
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43
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Kendrick AA, Dickey AM, Redwine WB, Tran PT, Vaites LP, Dzieciatkowska M, Harper JW, Reck-Peterson SL. Hook3 is a scaffold for the opposite-polarity microtubule-based motors cytoplasmic dynein-1 and KIF1C. J Cell Biol 2019; 218:2982-3001. [PMID: 31320392 PMCID: PMC6719453 DOI: 10.1083/jcb.201812170] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 05/06/2019] [Accepted: 06/21/2019] [Indexed: 01/06/2023] Open
Abstract
The unidirectional and opposite-polarity microtubule-based motors, dynein and kinesin, drive long-distance intracellular cargo transport. Cellular observations suggest that opposite-polarity motors may be coupled. We recently identified an interaction between the cytoplasmic dynein-1 activating adaptor Hook3 and the kinesin-3 KIF1C. Here, using in vitro reconstitutions with purified components, we show that KIF1C and dynein/dynactin can exist in a complex scaffolded by Hook3. Full-length Hook3 binds to and activates dynein/dynactin motility. Hook3 also binds to a short region in the "tail" of KIF1C, but unlike dynein/dynactin, this interaction does not activate KIF1C. Hook3 scaffolding allows dynein to transport KIF1C toward the microtubule minus end, and KIF1C to transport dynein toward the microtubule plus end. In cells, KIF1C can recruit Hook3 to the cell periphery, although the cellular role of the complex containing both motors remains unknown. We propose that Hook3's ability to scaffold dynein/dynactin and KIF1C may regulate bidirectional motility, promote motor recycling, or sequester the pool of available dynein/dynactin activating adaptors.
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Affiliation(s)
- Agnieszka A Kendrick
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA
| | - Andrea M Dickey
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA
| | - William B Redwine
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA
- Department of Cell Biology, Harvard Medical School, Boston, MA
| | - Phuoc Tien Tran
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA
| | | | - Monika Dzieciatkowska
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, CO
| | - J Wade Harper
- Department of Cell Biology, Harvard Medical School, Boston, MA
| | - Samara L Reck-Peterson
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA
- Section of Cell and Developmental Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, CA
- Howard Hughes Medical Institute, Chevy Chase, MD
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44
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Keidar L, Gerlitz G, Kshirsagar A, Tsoory M, Olender T, Wang X, Yang Y, Chen YS, Yang YG, Voineagu I, Reiner O. Interplay of LIS1 and MeCP2: Interactions and Implications With the Neurodevelopmental Disorders Lissencephaly and Rett Syndrome. Front Cell Neurosci 2019; 13:370. [PMID: 31474834 PMCID: PMC6703185 DOI: 10.3389/fncel.2019.00370] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 07/30/2019] [Indexed: 12/30/2022] Open
Abstract
LIS1 is the main causative gene for lissencephaly, while MeCP2 is the main causative gene for Rett syndrome, both of which are neurodevelopmental diseases. Here we report nuclear functions for LIS1 and identify previously unrecognized physical and genetic interactions between the products of these two genes in the cell nucleus, that has implications on MeCP2 organization, neuronal gene expression and mouse behavior. Reduced LIS1 levels affect the association of MeCP2 with chromatin. Transcriptome analysis of primary cortical neurons derived from wild type, Lis1±, MeCP2−/y, or double mutants mice revealed a large overlap in the differentially expressed (DE) genes between the various mutants. Overall, our findings provide insights on molecular mechanisms involved in the neurodevelopmental disorders lissencephaly and Rett syndrome caused by dysfunction of LIS1 and MeCP2, respectively.
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Affiliation(s)
- Liraz Keidar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Gabi Gerlitz
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Aditya Kshirsagar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Michael Tsoory
- Department of Veterinary Resources, Weizmann Institute of Science, Rehovot, Israel
| | - Tsviya Olender
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Xing Wang
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Ying Yang
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Yu-Sheng Chen
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Yun-Gui Yang
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Irina Voineagu
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Orly Reiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
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45
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Lecland N, Hsu CY, Chemin C, Merdes A, Bierkamp C. Epidermal development requires ninein for spindle orientation and cortical microtubule organization. Life Sci Alliance 2019; 2:2/2/e201900373. [PMID: 30923192 PMCID: PMC6441496 DOI: 10.26508/lsa.201900373] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 03/12/2019] [Accepted: 03/12/2019] [Indexed: 12/12/2022] Open
Abstract
In the epidermis, ninein affects spindle orientation of progenitor cells, as well as cortical microtubule organization, desmosome assembly, and lamellar body secretion in differentiating cells. In mammalian skin, ninein localizes to the centrosomes of progenitor cells and relocates to the cell cortex upon differentiation of keratinocytes, where cortical arrays of microtubules are formed. To examine the function of ninein in skin development, we use epidermis-specific and constitutive ninein-knockout mice to demonstrate that ninein is necessary for maintaining regular protein levels of the differentiation markers filaggrin and involucrin, for the formation of desmosomes, for the secretion of lamellar bodies, and for the formation of the epidermal barrier. Ninein-deficient mice are viable but develop a thinner skin with partly impaired epidermal barrier. We propose two underlying mechanisms: first, ninein contributes to spindle orientation during the division of progenitor cells, whereas its absence leads to misoriented cell divisions, altering the pool of progenitor cells. Second, ninein is required for the cortical organization of microtubules in differentiating keratinocytes, and for the cortical re-localization of microtubule-organizing proteins, and may thus affect any mechanisms that depend on localized microtubule-dependent transport.
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Affiliation(s)
- Nicolas Lecland
- Centre de Biologie du Développement, Centre de Biologie Intégrative, Université Paul Sabatier/CNRS (Centre National de la Recherche Scientifique), Toulouse, France
| | - Chiung-Yueh Hsu
- Centre de Biologie du Développement, Centre de Biologie Intégrative, Université Paul Sabatier/CNRS (Centre National de la Recherche Scientifique), Toulouse, France
| | - Cécile Chemin
- Centre de Biologie du Développement, Centre de Biologie Intégrative, Université Paul Sabatier/CNRS (Centre National de la Recherche Scientifique), Toulouse, France
| | - Andreas Merdes
- Centre de Biologie du Développement, Centre de Biologie Intégrative, Université Paul Sabatier/CNRS (Centre National de la Recherche Scientifique), Toulouse, France
| | - Christiane Bierkamp
- Centre de Biologie du Développement, Centre de Biologie Intégrative, Université Paul Sabatier/CNRS (Centre National de la Recherche Scientifique), Toulouse, France
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46
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Abstract
Cytoplasmic dynein-1 (hereafter dynein) is an essential cellular motor that drives the movement of diverse cargos along the microtubule cytoskeleton, including organelles, vesicles and RNAs. A long-standing question is how a single form of dynein can be adapted to a wide range of cellular functions in both interphase and mitosis. Recent progress has provided new insights - dynein interacts with a group of activating adaptors that provide cargo-specific and/or function-specific regulation of the motor complex. Activating adaptors such as BICD2 and Hook1 enhance the stability of the complex that dynein forms with its required activator dynactin, leading to highly processive motility toward the microtubule minus end. Furthermore, activating adaptors mediate specific interactions of the motor complex with cargos such as Rab6-positive vesicles or ribonucleoprotein particles for BICD2, and signaling endosomes for Hook1. In this Cell Science at a Glance article and accompanying poster, we highlight the conserved structural features found in dynein activators, the effects of these activators on biophysical parameters, such as motor velocity and stall force, and the specific intracellular functions they mediate.
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Affiliation(s)
- Mara A Olenick
- University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Erika L F Holzbaur
- University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
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47
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Aspergillus nidulans in the post-genomic era: a top-model filamentous fungus for the study of signaling and homeostasis mechanisms. Int Microbiol 2019; 23:5-22. [DOI: 10.1007/s10123-019-00064-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 01/30/2019] [Accepted: 02/04/2019] [Indexed: 02/07/2023]
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48
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Takeshita N. Control of Actin and Calcium for Chitin Synthase Delivery to the Hyphal Tip of Aspergillus. Curr Top Microbiol Immunol 2019; 425:113-129. [PMID: 31974757 DOI: 10.1007/82_2019_193] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Filamentous fungi are covered by a cell wall consisting mainly of chitin and glucan. The synthesis of chitin, a β-1,4-linked homopolymer of N-acetylglucosamine, is essential for hyphal morphogenesis. Fungal chitin synthases are integral membrane proteins that have been classified into seven classes. ChsB, a class III chitin synthase, is known to play a key role in hyphal tip growth and has been used here as a model to understand the cell biology of cell wall biosynthesis in Aspergillus nidulans. Chitin synthases are transported on secretory vesicles to the plasma membrane for new cell wall synthesis. Super-resolution localization imaging as a powerful biophysical approach indicated dynamics of the Spitzenkörper where spatiotemporally regulated exocytosis and cell extension, whereas high-speed pulse-chase imaging has revealed ChsB transport mechanism mediated by kinesin-1 and myosin-5. In addition, live imaging analysis showed correlations among intracellular Ca2+ levels, actin assembly, and exocytosis in growing hyphal tips. This suggests that pulsed Ca2+ influxes coordinate the temporal control of actin assembly and exocytosis, which results in stepwise cell extension. It is getting clear that turgor pressure and cell wall pressure are involved in the activation of Ca2+ channels for Ca2+ oscillation and cell extension. Here the cell wall synthesis and tip growth meet again.
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Affiliation(s)
- Norio Takeshita
- Microbiology Research Center for Sustainability (MiCS), Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan.
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Qiu R, Zhang J, Xiang X. p25 of the dynactin complex plays a dual role in cargo binding and dynactin regulation. J Biol Chem 2018; 293:15606-15619. [PMID: 30143531 DOI: 10.1074/jbc.ra118.004000] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 08/23/2018] [Indexed: 01/13/2023] Open
Abstract
Cytoplasmic dynein binds its cargoes via the dynactin complex and cargo adapters, and the dynactin pointed-end protein p25 is required for dynein-dynactin binding to the early endosomal dynein adapter HookA (Hook in the fungus Aspergillus nidulans). However, it is unclear whether the HookA-dynein-dynactin interaction requires p27, another pointed-end protein forming heterodimers with p25 within vertebrate dynactin. Here, live-cell imaging and biochemical pulldown experiments revealed that although p27 is a component of the dynactin complex in A. nidulans, it is dispensable for dynein-dynactin to interact with ΔC-HookA (cytosolic HookA lacking its early endosome-binding C terminus) and is not critical for dynein-mediated early endosome transport. Using mutagenesis, imaging, and biochemical approaches, we found that several p25 regions are required for the ΔC-HookA-dynein-dynactin interaction, with the N terminus and loop1 being the most critical regions. Interestingly, p25 was also important for the microtubule (MT) plus-end accumulation of dynactin. This p25 function in dynactin localization also involved p25's N terminus and the loop1 critical for the ΔC-HookA-dynein-dynactin interaction. Given that dynactin's MT plus-end localization does not require HookA and that the kinesin-1-dependent plus-end accumulation of dynactin is unnecessary for the ΔC-HookA-dynein-dynactin interaction, our results indicate that p25 plays a dual role in cargo binding and dynactin regulation. As cargo adapters are implicated in dynein activation via binding to dynactin's pointed end to switch the conformation of p150, a major dynactin component, our results suggest p25 as a critical pointed-end protein involved in this process.
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Affiliation(s)
- Rongde Qiu
- From the Department of Biochemistry and Molecular Biology, the Uniformed Services University-F. Edward Hébert School of Medicine, Bethesda, Maryland 20814
| | - Jun Zhang
- From the Department of Biochemistry and Molecular Biology, the Uniformed Services University-F. Edward Hébert School of Medicine, Bethesda, Maryland 20814
| | - Xin Xiang
- From the Department of Biochemistry and Molecular Biology, the Uniformed Services University-F. Edward Hébert School of Medicine, Bethesda, Maryland 20814
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The actin capping protein in Aspergillus nidulans enhances dynein function without significantly affecting Arp1 filament assembly. Sci Rep 2018; 8:11419. [PMID: 30061726 PMCID: PMC6065395 DOI: 10.1038/s41598-018-29818-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 07/18/2018] [Indexed: 11/08/2022] Open
Abstract
The minus-end-directed microtubule motor cytoplasmic dynein requires the dynactin complex for in vivo functions. The backbone of the vertebrate dynactin complex is the Arp1 (actin-related protein 1) mini-filament whose barbed end binds to the heterodimeric actin capping protein. However, it is unclear whether the capping protein is a dynactin component in lower eukaryotic organisms, especially because it does not appear to be a component of the budding yeast dynactin complex. Here our biochemical data show that the capping protein is a component of the dynactin complex in the filamentous fungus Aspergillus nidulans. Moreover, deletion of the gene encoding capping protein alpha (capA) results in a defect in both nuclear distribution and early-endosome transport, two dynein-mediated processes. However, the defect in either process is less severe than that exhibited by a dynein heavy chain mutant or the ∆p25 mutant of dynactin. In addition, loss of capping protein does not significantly affect the assembly of the dynactin Arp1 filament or the formation of the dynein-dynactin-∆C-HookA (Hook in A. nidulans) complex. These results suggest that fungal capping protein is not important for Arp1 filament assembly but its presence is required for enhancing dynein function in vivo.
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