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Nick P. Move backward, forward signals. PROTOPLASMA 2019; 256:1171-1172. [PMID: 31401691 DOI: 10.1007/s00709-019-01432-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 08/06/2019] [Indexed: 06/10/2023]
Affiliation(s)
- Peter Nick
- Botanical Institute, Karlsruher Institut für Technologie, Karlsruhe, Germany.
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2
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Kobayashi T, Miyashita T, Murayama T, Toyoshima YY. Dynactin has two antagonistic regulatory domains and exerts opposing effects on dynein motility. PLoS One 2017; 12:e0183672. [PMID: 28850609 PMCID: PMC5574551 DOI: 10.1371/journal.pone.0183672] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 07/31/2017] [Indexed: 01/01/2023] Open
Abstract
Dynactin is a dynein-regulating protein that increases the processivity of dynein movement on microtubules. Recent studies have shown that a tripartite complex of dynein–dynactin–Bicaudal D2 is essential for highly processive movement. To elucidate the regulation of dynein motility by dynactin, we focused on two isoforms (A and B) of dynactin 1 (DCTN1), the largest subunit of dynactin that contains both microtubule- and dynein-binding domains. The only difference between the primary structures of the two isoforms is that DCTN1B lacks the K-rich domain, a cluster of basic residues. We measured dynein motility by single molecule observation of recombinant dynein and dynactin. Whereas the tripartite complex containing DCTN1A exhibited highly processive movement, the complex containing DCTN1B dissociated from microtubules with no apparent processive movement. This inhibitory effect of DCTN1B was caused by reductions of the microtubule-binding affinities of both dynein and dynactin, which was attributed to the coiled-coil 1 domain of DCTN1. In DCTN1A, the K-rich domain antagonized these inhibitory effects. Therefore, dynactin has two antagonistic domains and promotes or suppresses dynein motility to accomplish correct localization and functions of dynein within a cell.
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Affiliation(s)
- Takuya Kobayashi
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Takuya Miyashita
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Takashi Murayama
- Department of Pharmacology, Juntendo University School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Yoko Y. Toyoshima
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan
- * E-mail:
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3
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Esue O, Carson AA, Tseng Y, Wirtz D. A direct interaction between actin and vimentin filaments mediated by the tail domain of vimentin. J Biol Chem 2006; 281:30393-9. [PMID: 16901892 DOI: 10.1074/jbc.m605452200] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The assembly and organization of the three major eukaryotic cytoskeleton proteins, actin, microtubules, and intermediate filaments, are highly interdependent. Through evolution, cells have developed specialized multifunctional proteins that mediate the cross-linking of these cytoskeleton filament networks. Here we test the hypothesis that two of these filamentous proteins, F-actin and vimentin filament, can interact directly, i.e. in the absence of auxiliary proteins. Through quantitative rheological studies, we find that a mixture of vimentin/actin filament network features a significantly higher stiffness than that of networks containing only actin filaments or only vimentin filaments. Maximum inter-filament interaction occurs at a vimentin/actin molar ratio of 3 to 1. Mixed networks of actin and tailless vimentin filaments show low mechanical stiffness and much weaker inter-filament interactions. Together with the fact that cells featuring prominent vimentin and actin networks are much stiffer than their counterparts lacking an organized actin or vimentin network, these results suggest that actin and vimentin filaments can interact directly through the tail domain of vimentin and that these inter-filament interactions may contribute to the overall mechanical integrity of cells and mediate cytoskeletal cross-talk.
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Affiliation(s)
- Osigwe Esue
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
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4
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Di Y, Li J, Fang J, Xu Z, He X, Zhang F, Ling J, Li X, Xu D, Li L, Li YY, Huo K. Cloning and characterization of a novel gene which encodes a protein interacting with the mitosis-associated kinase-like protein NTKL. J Hum Genet 2004; 48:315-321. [PMID: 12783284 DOI: 10.1007/s10038-003-0031-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2003] [Accepted: 04/07/2003] [Indexed: 10/25/2022]
Abstract
NTKL is an evolutionarily conserved kinase-like protein. The cell-cycle-dependent centrosomal localization of NTKL suggested that it was involved in centrosome-related cellular function. The mouse NTKL protein is highly homologous with human NTKL. A novel mouse protein was identified as an NTKL-binding protein (NTKL-BP1) by yeast two-hybrid screening, and the full-length cDNA was amplified based on the result of a sequence data analysis cloning strategy. The full-length cDNA sequence of the NTKL-BP1 gene consists of 2,537 bp, which encode 368 amino acids. A database search revealed that homologues of NTKL-BP1 exist in different organisms, including Arabidopsis thaliana, Drosophila melanogaster, Plasmodium falciparum, Geobacter metallireducens, Anopheles gambiae and human. It suggests that NTKL-BP1 is an evolutionarily conserved protein. The expression of NTKL-BP1 was observed in multiple normal mouse tissues. The interaction of the two proteins was confirmed by co-immunoprecipitation. Moreover, immunofluorescent staining indicated that NTKL and NTKL-BP1 were all localized in the cytoplasm.
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Affiliation(s)
- Yujun Di
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 200433, Shanghai, PR China
| | - Jinjun Li
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, 200032, Shanghai, PR China
| | - Ji Fang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 200433, Shanghai, PR China
| | - Zhigang Xu
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 200433, Shanghai, PR China
| | - Xianghuo He
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, 200032, Shanghai, PR China
| | - Fengrui Zhang
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, 200032, Shanghai, PR China
| | - Jiqiang Ling
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 200433, Shanghai, PR China
| | - Xinrui Li
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 200433, Shanghai, PR China
| | - Dongbin Xu
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 200433, Shanghai, PR China
| | - Li Li
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 200433, Shanghai, PR China
| | - Yu-Yang Li
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 200433, Shanghai, PR China
| | - Keke Huo
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 200433, Shanghai, PR China.
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5
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Ishikawa T, Kawai C, Sano M, Minatogawa Y. Peroxisomes exist in growth cones and move anterogradely and retrogradely in neurites of PC12D cells. Exp Cell Res 2001; 266:260-9. [PMID: 11399054 DOI: 10.1006/excr.2001.5226] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Localization and movement of peroxisomes have been investigated in neurites of a subline of PC12 pheochromocytoma cells (PC12D cells). The cells were transfected with a construct encoding the green fluorescent protein and bearing the C-terminal peroxisomal targeting signal 1 SKL motif (-Ser-Lys-Leu-COOH). Peroxisomes were detected as green punctate fluorescent signals. Many peroxisomes were observed in neurites of PC12D cells, especially in neural terminal-like structures, growth cones, varicosities, and branch points. Growth cones containing many peroxisomes were active, since they extended several long filopodias. Existence of peroxisomes in growth cones and neuronal terminal-like structures suggests that peroxisomes might have some role in neuronal extension and nerve terminal functioning. Peroxisomal motility was analyzed by time-lapse imaging using a fluorescence microscope at 25 degrees C. Peroxisomes were transported bidirectionally in neurites, i.e., through anterograde and retrograde transport. This result suggests that peroxisomes move to growth cones and neural terminals from the PC12D cell body, play some role in these parts, and go back to cell body.
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Affiliation(s)
- T Ishikawa
- Department of Biochemistry, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, 701-0192, Japan.
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6
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Susalka SJ, Hancock WO, Pfister KK. Distinct cytoplasmic dynein complexes are transported by different mechanisms in axons. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1496:76-88. [PMID: 10722878 DOI: 10.1016/s0167-4889(00)00010-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In neurons, cytoplasmic dynein is synthesized in the cell body, but its function is to move cargo from the axon back to the cell body. Dynein must therefore be delivered to the axon and its motor activity must be regulated during axonal transport. Cytoplasmic dynein is a large protein complex composed of a number of different subunits. The dynein heavy chains contain the motor domains and the intermediate chains are involved in binding the complex to cargo. Five different intermediate chain polypeptides, which are the result of the alternative splicing of the two intermediate chain genes, have been identified. We have characterized two distinct pools of dynein that are transported from the cell body along the axon by different mechanisms. One pool, which contains the ubiquitous intermediate chain, is associated with the membranous organelles transported by kinesin in the fast transport component. The other pool, which contains the other developmentally regulated intermediate chains, is transported in slow component b. The mechanism of dynein regulation will therefore depend on which pool of dynein is recruited to function as the retrograde motor. In addition, the properties of the large pool of dynein associated with actin in slow component b are consistent with the hypothesis that this dynein may be the motor for microtubule transport in the axon.
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Affiliation(s)
- S J Susalka
- Department of Cell Biology, Box 439, School of Medicine, University of Virginia, Charlottesville, VA 22908, USA
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7
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Gönczy P, Pichler S, Kirkham M, Hyman AA. Cytoplasmic dynein is required for distinct aspects of MTOC positioning, including centrosome separation, in the one cell stage Caenorhabditis elegans embryo. J Cell Biol 1999; 147:135-50. [PMID: 10508861 PMCID: PMC2164971 DOI: 10.1083/jcb.147.1.135] [Citation(s) in RCA: 360] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/1999] [Accepted: 08/23/1999] [Indexed: 11/22/2022] Open
Abstract
We have investigated the role of cytoplasmic dynein in microtubule organizing center (MTOC) positioning using RNA-mediated interference (RNAi) in Caenorhabditis elegans to deplete the product of the dynein heavy chain gene dhc-1. Analysis with time-lapse differential interference contrast microscopy and indirect immunofluorescence revealed that pronuclear migration and centrosome separation failed in one cell stage dhc-1 (RNAi) embryos. These phenotypes were also observed when the dynactin components p50/dynamitin or p150(Glued) were depleted with RNAi. Moreover, in 15% of dhc-1 (RNAi) embryos, centrosomes failed to remain in proximity of the male pronucleus. When dynein heavy chain function was diminished only partially with RNAi, centrosome separation took place, but orientation of the mitotic spindle was defective. Therefore, cytoplasmic dynein is required for multiple aspects of MTOC positioning in the one cell stage C. elegans embryo. In conjunction with our observation of cytoplasmic dynein distribution at the periphery of nuclei, these results lead us to propose a mechanism in which cytoplasmic dynein anchored on the nucleus drives centrosome separation.
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Affiliation(s)
- P Gönczy
- European Molecular Biology Laboratory, Heidelberg, D-69117 Germany.
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8
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Pfister KK. Cytoplasmic dynein and microtubule transport in the axon: the action connection. Mol Neurobiol 1999; 20:81-91. [PMID: 10966115 DOI: 10.1007/bf02742435] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The neuron uses two families of microtubule-based motors for fast axonal transport, kinesin, and cytoplasmic dynein. Cytoplasmic dynein moves membranous organelles from the distal regions of the axon to the cell body. Because dynein is synthesized in the cell body, it must first be delivered to the axon tip. It has recently been shown that cytoplasmic dynein is moved from the cell body along the axon by two different mechanisms. A small amount is associated with fast anterograde transport, the membranous organelles moved by kinesin. Most of the dynein is transported in slow component b, the actin-based transport compartment. Dynactin, a protein complex that binds dynein, is also transported in slow component b. The dynein in slow component b binds to microtubules in an ATP-dependent manner in vitro, suggesting that this dynein is enzymatically active. The finding that functionally active dynein, and dynactin, are associated with the actin-based transport compartment suggests a mechanism whereby dynein anchored to the actin cytoskeleton via dynactin provides the motive force for microtubule movement in the axon.
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Affiliation(s)
- K K Pfister
- Cell Biology Department, School of Medicine, University of Virginia, Charlottesville 22908-0732, USA
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Robinson JT, Wojcik EJ, Sanders MA, McGrail M, Hays TS. Cytoplasmic dynein is required for the nuclear attachment and migration of centrosomes during mitosis in Drosophila. J Cell Biol 1999; 146:597-608. [PMID: 10444068 PMCID: PMC2150560 DOI: 10.1083/jcb.146.3.597] [Citation(s) in RCA: 189] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Cytoplasmic dynein is a multisubunit minus-end-directed microtubule motor that serves multiple cellular functions. Genetic studies in Drosophila and mouse have demonstrated that dynein function is essential in metazoan organisms. However, whether the essential function of dynein reflects a mitotic requirement, and what specific mitotic tasks require dynein remains controversial. Drosophila is an excellent genetic system in which to analyze dynein function in mitosis, providing excellent cytology in embryonic and somatic cells. We have used previously characterized recessive lethal mutations in the dynein heavy chain gene, Dhc64C, to reveal the contributions of the dynein motor to mitotic centrosome behavior in the syncytial embryo. Embryos lacking wild-type cytoplasmic dynein heavy chain were analyzed by in vivo analysis of rhodamine-labeled microtubules, as well as by immunofluorescence in situ methods. Comparisons between wild-type and Dhc64C mutant embryos reveal that dynein function is required for the attachment and migration of centrosomes along the nuclear envelope during interphase/prophase, and to maintain the attachment of centrosomes to mitotic spindle poles. The disruption of these centrosome attachments in mutant embryos reveals a critical role for dynein function and centrosome positioning in the spatial organization of the syncytial cytoplasm of the developing embryo.
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Affiliation(s)
- John T. Robinson
- University of Minnesota, Department of Genetics, Cell Biology and Development, St. Paul, Minnesota 55108-1095
| | - Edward J. Wojcik
- University of Minnesota, Department of Genetics, Cell Biology and Development, St. Paul, Minnesota 55108-1095
| | - Mark A. Sanders
- University of Minnesota, Department of Genetics, Cell Biology and Development, St. Paul, Minnesota 55108-1095
| | - Maura McGrail
- University of Minnesota, Department of Genetics, Cell Biology and Development, St. Paul, Minnesota 55108-1095
| | - Thomas S. Hays
- University of Minnesota, Department of Genetics, Cell Biology and Development, St. Paul, Minnesota 55108-1095
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10
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Beckwith SM, Roghi CH, Liu B, Ronald Morris N. The "8-kD" cytoplasmic dynein light chain is required for nuclear migration and for dynein heavy chain localization in Aspergillus nidulans. J Cell Biol 1998; 143:1239-47. [PMID: 9832552 PMCID: PMC2133080 DOI: 10.1083/jcb.143.5.1239] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/1998] [Revised: 10/06/1998] [Indexed: 11/26/2022] Open
Abstract
The heavy chain of cytoplasmic dynein is required for nuclear migration in Aspergillus nidulans and other fungi. Here we report on a new gene required for nuclear migration, nudG, which encodes a homologue of the "8-kD" cytoplasmic dynein light chain (CDLC). We demonstrate that the temperature sensitive nudG8 mutation inhibits nuclear migration and growth at restrictive temperature. This mutation also inhibits asexual and sexual sporulation, decreases the intracellular concentration of the nudG CDLC protein and causes the cytoplasmic dynein heavy chain to be absent from the mycelial tip, where it is normally located in wild-type mycelia. Coimmunoprecipitation experiments with antibodies against the cytoplasmic dynein heavy chain (CDHC) and the nudG CDLC demonstrated that some fraction of the cytoplasmic dynein light chain is in a protein complex with the CDHC. Sucrose gradient sedimentation analysis, however, showed that not all of the NUDG protein is complexed with the heavy chain. A double mutant carrying a cytoplasmic dynein heavy chain deletion plus a temperature-sensitive nudG mutation grew no more slowly at restrictive temperature than a strain with only the CDHC deletion. This result demonstrates that the effect of the nudG mutation on nuclear migration and growth is mediated through an interaction with the CDHC rather than with some other molecule (e.g., myosin-V) with which the 8-kD CDLC might theoretically interact.
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Affiliation(s)
- S M Beckwith
- Department of Pharmacology, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA
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11
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Kamal A, Ying Y, Anderson RG. Annexin VI-mediated loss of spectrin during coated pit budding is coupled to delivery of LDL to lysosomes. J Cell Biol 1998; 142:937-47. [PMID: 9722607 PMCID: PMC2132873 DOI: 10.1083/jcb.142.4.937] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/1998] [Revised: 06/30/1998] [Indexed: 02/08/2023] Open
Abstract
Previously we reported that annexin VI is required for the budding of clathrin-coated pits from human fibroblast plasma membranes in vitro. Here we show that annexin VI bound to the NH2-terminal 28-kD portion of membrane spectrin is as effective as cytosolic annexin VI in supporting coated pit budding. Annexin VI-dependent budding is accompanied by the loss of approximately 50% of the spectrin from the membrane and is blocked by the cysteine protease inhibitor N-acetyl-leucyl-leucyl-norleucinal (ALLN). Incubation of fibroblasts in the presence of ALLN initially blocks the uptake of low density lipoprotein (LDL), but the cells recover after 1 h and internalize LDL with normal kinetics. The LDL internalized under these conditions, however, fails to migrate to the center of the cell and is not degraded. ALLN-treated cells have twice as many coated pits and twofold more membrane clathrin, suggesting that new coated pits have assembled. Annexin VI is not required for the budding of these new coated pits and ALLN does not inhibit. Finally, microinjection of a truncated annexin VI that inhibits budding in vitro has the same effect on LDL internalization as ALLN. These findings suggest that fibroblasts are able to make at least two types of coated pits, one of which requires the annexin VI-dependent activation of a cysteine protease to disconnect the clathrin lattice from the spectrin membrane cytoskeleton during the final stages of budding.
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Affiliation(s)
- A Kamal
- Department of Cell Biology and Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas 75235, USA
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12
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Beck KA, Nelson WJ. A spectrin membrane skeleton of the Golgi complex. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1404:153-60. [PMID: 9714784 DOI: 10.1016/s0167-4889(98)00054-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The existence of a Golgi-localized membrane cytoskeleton has been revealed by the identification of two major components of the spectrin membrane skeleton, spectrin and ankyrin, that associate with the Golgi complex. Golgi spectrin was identified with an antibody specific for the beta-subunit of the erythroid isoform of spectrin (beta1Sigma1). This antibody recognizes a 220 kDa polypeptide that localizes to discrete regions of the Golgi complex and associates with Golgi membranes in a Brefeldin A sensitive manner. Two isoforms of Golgi ankyrin have been identified: a 119 kDa form (AnkG119) which represents a truncated, alternatively spliced isoform of a recently cloned novel ankyrin of the nervous system AnkG, and a larger 195 kDa ankyrin (Ank195) that cross-reacts with antibodies to erythrocyte ankyrin. A Golgi localized membrane skeleton composed of these unique membrane skeleton isoforms could serve a variety of important functions, including the maintenance of Golgi structural organization and the formation of discrete membrane domains within Golgi compartments.
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Affiliation(s)
- K A Beck
- Department of Cell Biology and Human Anatomy, School of Medicine, University of California, Davis, CA 95616, USA
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13
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Abstract
Polarized growth, secretion of exoenzymes, organelle inheritance, and organelle positioning require vectorial transport along cytoskeletal elements. The discovery of molecular motors and intensive studies on their biological function during the past 3 years confirmed a central role of these mechanoenzymes in morphogenesis and development of yeasts and filamentous fungi. Saccharomyces cerevisiae proved to be an excellent model system, in which the complete set of molecular motors is presumed to be known. Genetic studies combined with cell biological methods revealed unexpected functional relationships between these motors and has greatly improved our understanding of nuclear migration, exocytosis, and endocytosis in yeasts. Tip growth of elongated hyphae, compared to budding, however, does require vectorial transport over long distances. The identification of ubiquitous motors that are not present in yeast indicates that studies on filamentous fungi might be helpful to elucidate the role of motors in long-distance organelle transport within higher eukaryotic cells. Copyright 1998 Academic Press.
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Affiliation(s)
- G Steinberg
- Institute for Genetics and Microbiology, Ludwig Maximilian University, Maria-Ward-Strasse 1a, Munich, 80638, Germany
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14
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Robertson AM, Allan VJ. Cell cycle regulation of organelle transport. PROGRESS IN CELL CYCLE RESEARCH 1998; 3:59-75. [PMID: 9552407 DOI: 10.1007/978-1-4615-5371-7_6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Microtubule- and actin-based motors play a wide range of vital roles in the organisation and function of cells during both interphase and mitosis, all of which are likely to be under strict control. Here, we describe how one of these roles--the movement of membranes--is regulated through the cell cycle. Organelle movement in many species is greatly reduced in mitosis as compared to interphase, and this change occurs concomitantly with an inhibition of most membrane traffic functions. Data from in vitro studies is shedding light on how microtubule motor regulation may be achieved.
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Affiliation(s)
- A M Robertson
- School of Biological Sciences, University of Manchester, United Kingdom
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15
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Abstract
Huntingtin is the protein product of the gene for Huntington's disease (HD) and carries a polyglutamine repeat that is expanded in HD (>36 units). Huntingtin-associated protein (HAP1) is a neuronal protein and binds to huntingtin in association with the polyglutamine repeat. Like huntingtin, HAP1 has been found to be a cytoplasmic protein associated with membranous organelles, suggesting the existence of a protein complex including HAP1, huntingtin, and other proteins. Using the yeast two-hybrid system, we found that HAP1 also binds to dynactin P150(Glued) (P150), an accessory protein for cytoplasmic dynein that participates in microtubule-dependent retrograde transport of membranous organelles. An in vitro binding assay showed that both huntingtin and P150 selectively bound to a glutathione transferase (GST)-HAP1 fusion protein. An immunoprecipitation assay demonstrated that P150 and huntingtin coprecipitated with HAP1 from rat brain cytosol. Western blot analysis revealed that HAP1 was enriched in rat brain microtubules and comigrated with P150 and huntingtin in sucrose gradients. Immunofluorescence showed that transfected HAP1 colocalized with P150 and huntingtin in human embryonic kidney (HEK) 293 cells. We propose that HAP1, P150, and huntingtin are present in a protein complex that may participate in dynein-dynactin-associated intracellular transport.
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16
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Nick P. Signaling to The Microtubular Cytoskeleton in Plants. INTERNATIONAL REVIEW OF CYTOLOGY 1998. [DOI: 10.1016/s0074-7696(08)62178-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Abe TK, Tanaka H, Iwanaga T, Odani S, Kuwano R. The presence of the 50-kDa subunit of dynactin complex in the nerve growth cone. Biochem Biophys Res Commun 1997; 233:295-9. [PMID: 9144527 DOI: 10.1006/bbrc.1997.6447] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Membrane proteins in growth cone-enriched and growth cone-non-enriched fractions prepared from neonatal mouse brain were separated by lectin-affinity and ion exchange chromatographies, 2D-PAGE, and SDS-PAGE. Partial amino acid sequences of the proteins concentrated in the growth cone-enriched fraction were determined. We found that one such protein, gmp23-48k, corresponds to the 50-kDa subunit (p50) of the dynactin complex. An antibody raised against gmp23-48k strongly reacted with growth cones of differentiated neuronal precursor cells. Immunoblot analyses revealed that gmp23-48k was present both in membrane and in soluble fractions of neonatal brain. However, the amount of gmp23-48k in the membrane fraction greatly decreased in adult brain. These results suggest a special role of membrane-associated gmp23-48k/p50 in synapse formation during brain development.
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Affiliation(s)
- T K Abe
- Research Laboratory for Molecular Genetics, Niigata University, Asahimachi, Japan
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18
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Wiemer EA, Wenzel T, Deerinck TJ, Ellisman MH, Subramani S. Visualization of the peroxisomal compartment in living mammalian cells: dynamic behavior and association with microtubules. J Cell Biol 1997; 136:71-80. [PMID: 9008704 PMCID: PMC2132450 DOI: 10.1083/jcb.136.1.71] [Citation(s) in RCA: 141] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/1996] [Revised: 10/15/1996] [Indexed: 02/03/2023] Open
Abstract
Peroxisomes in living CV1 cells were visualized by targeting the green fluorescent protein (GFP) to this subcellular compartment through the addition of a COOH-terminal peroxisomal targeting signal 1 (GFP-PTS1). The organelle dynamics were examined and analyzed using time-lapse confocal laser scanning microscopy. Two types of movement could be distinguished: a relatively slow, random, vibration-like movement displayed by the majority (approximately 95%) of the peroxisomes, and a saltatory, fast directional movement displayed by a small subset (approximately 5%) of the peroxisomes. In the latter instance, peak velocities up to 0.75 micron/s and sustained directional velocities up to 0.45 micron/s over 11.5 microns were recorded. Only the directional type of motion appeared to be energy dependent, whereas the vibrational movement continued even after the cells were depleted of energy. Treatment of cells, transiently expressing GFP-PTS1, with microtubule-destabilizing agents such as nocodazole, vinblastine, and demecolcine clearly altered peroxisome morphology and subcellular distribution and blocked the directional movement. In contrast, the microtubule-stabilizing compound paclitaxel, or the microfilament-destabilizing drugs cytochalasin B or D, did not exert these effects. High resolution confocal analysis of cells expressing GFP-PTS1 and stained with anti-tubulin antibodies revealed that many peroxisomes were associated with microtubules. The GFP-PTS1-labeled peroxisomes were found to distribute themselves in a stochastic, rather than ordered, manner to daughter cells at the time of mitosis.
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Affiliation(s)
- E A Wiemer
- Department of Biology, University of California at San Diego, La Jolla 92093-0322, USA
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Abstract
A family of proteins has been discovered over the past three years whose members have clear sequence homology to actin but are distinguished from actin by their structural and functional diversity. The ranks of this family, whose members are known as the actin-related proteins (arps), are expanding rapidly. Arps are but one branch of a larger superfamily which includes the actins, hsp/hsc70s, sugar kinases and several cell cycle proteins from bacteria. The existence of the superfamily has been inferred from tertiary structural data. In the case of the arps, their identification and classification has been based upon primary structural data. Placing the arps in a functional context is proving a slower process, although genetic and biochemical analyses are converging in several cases. In the past year, different arps have been linked to functions mediated by actin filaments (arp2 and arp3), microtubules (arp1) and the structural elements of chromatin (arp4 and arp6).
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Affiliation(s)
- S Frankel
- Department of Biology, Yale University, New Haven, CT 06520-8103, USA.
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Waterman-Storer CM, Holzbaur EL. The product of the Drosophila gene, Glued, is the functional homologue of the p150Glued component of the vertebrate dynactin complex. J Biol Chem 1996; 271:1153-9. [PMID: 8557644 DOI: 10.1074/jbc.271.2.1153] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
p150Glued is the largest polypeptide in the dynactin complex, a protein heteromultimer that binds to and may mediate the microtubule-based motor cytoplasmic dynein. Cloning of a cDNA encoding p150Glued from rat revealed 31% amino acid sequence identity with the product of the Drosophila gene, Glued. A dominant Glued mutation results in neuronal disruption; null mutations are lethal. However, the Glued gene product has not been characterized. To determine whether the Glued polypeptide is functionally similar to vertebrate p150Glued, we characterized the Glued protein in the Drosophila S-2 cell line. Antibodies raised against Glued were used to demonstrate that this protein sediments exclusively at 20 S, and associates with microtubules in a salt- and ATP-dependent manner. Immunoprecipitations from S-2 cytosol with the anti-Glued antibody resulted in the co-precipitation of subunits of both cytoplasmic dynein and the dynactin complex. An affinity column with covalently bound Glued protein retained cytoplasmic dynein from S-2 cytosol. Based on these observations, we conclude that Glued is a component of a dynactin complex in Drosophila and binds to cytoplasmic dynein, and therefore the mutant Glued phenotypes can be interpreted as resulting from a disruption in the function of the dynactin complex.
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Affiliation(s)
- C M Waterman-Storer
- Department of Animal Biology, University of Pennsylvania School of Veterinary Medicine, Philadelphia 19104-6046, USA
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