1
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Montgomery AC, Mendoza CS, Garbouchian A, Quinones GB, Bentley M. Polarized transport requires AP-1-mediated recruitment of KIF13A and KIF13B at the trans-Golgi. Mol Biol Cell 2024; 35:ar61. [PMID: 38446634 PMCID: PMC11151104 DOI: 10.1091/mbc.e23-10-0401] [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] [Indexed: 03/08/2024] Open
Abstract
Neurons are polarized cells that require accurate membrane trafficking to maintain distinct protein complements at dendritic and axonal membranes. The Kinesin-3 family members KIF13A and KIF13B are thought to mediate dendrite-selective transport, but the mechanism by which they are recruited to polarized vesicles and the differences in the specific trafficking role of each KIF13 have not been defined. We performed live-cell imaging in cultured hippocampal neurons and found that KIF13A is a dedicated dendrite-selective kinesin. KIF13B confers two different transport modes, dendrite- and axon-selective transport. Both KIF13s are maintained at the trans-Golgi network by interactions with the heterotetrameric adaptor protein complex AP-1. Interference with KIF13 binding to AP-1 resulted in disruptions to both dendrite- and axon-selective trafficking. We propose that AP-1 is the molecular link between the sorting of polarized cargoes into vesicles and the recruitment of kinesins that confer polarized transport.
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Affiliation(s)
- Andrew C Montgomery
- Department of Biological Sciences and the Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Christina S Mendoza
- Department of Biological Sciences and the Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Alex Garbouchian
- Department of Biological Sciences and the Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Geraldine B Quinones
- Department of Biological Sciences and the Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Marvin Bentley
- Department of Biological Sciences and the Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
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2
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Fan X, McKenney RJ. Control of motor landing and processivity by the CAP-Gly domain in the KIF13B tail. Nat Commun 2023; 14:4715. [PMID: 37543636 PMCID: PMC10404244 DOI: 10.1038/s41467-023-40425-4] [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: 08/11/2022] [Accepted: 07/27/2023] [Indexed: 08/07/2023] Open
Abstract
Microtubules are major components of the eukaryotic cytoskeleton. Posttranslational modifications (PTMs) of tubulin regulates interactions with microtubule-associated proteins (MAPs). One unique PTM is the cyclical removal and re-addition of the C-terminal tyrosine of α-tubulin and MAPs containing CAP-Gly domains specifically recognize tyrosinated microtubules. KIF13B, a long-distance transport kinesin, contains a conserved CAP-Gly domain, but the role of the CAP-Gly domain in KIF13B's motility along microtubules remains unknown. To address this, we investigate the interaction between KIF13B's CAP-Gly domain, and tyrosinated microtubules. We find that KIF13B's CAP-Gly domain influences the initial motor-microtubule interaction, as well as processive motility along microtubules. The effect of the CAP-Gly domain is enhanced when the motor domain is in the ADP state, suggesting an interplay between the N-terminal motor domain and C-terminal CAP-Gly domain. These results reveal that specialized kinesin tail domains play active roles in the initiation and continuation of motor movement.
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Affiliation(s)
- Xiangyu Fan
- Department of Molecular and Cellular Biology, University of California - Davis, 145 Briggs Hall, Davis, CA, 95616, USA
| | - Richard J McKenney
- Department of Molecular and Cellular Biology, University of California - Davis, 145 Briggs Hall, Davis, CA, 95616, USA.
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3
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Hildebrandt RP, Moss KR, Janusz-Kaminska A, Knudson LA, Denes LT, Saxena T, Boggupalli DP, Li Z, Lin K, Bassell GJ, Wang ET. Muscleblind-like proteins use modular domains to localize RNAs by riding kinesins and docking to membranes. Nat Commun 2023; 14:3427. [PMID: 37296096 PMCID: PMC10256740 DOI: 10.1038/s41467-023-38923-6] [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: 08/23/2022] [Accepted: 05/22/2023] [Indexed: 06/12/2023] Open
Abstract
RNA binding proteins (RBPs) act as critical facilitators of spatially regulated gene expression. Muscleblind-like (MBNL) proteins, implicated in myotonic dystrophy and cancer, localize RNAs to myoblast membranes and neurites through unknown mechanisms. We find that MBNL forms motile and anchored granules in neurons and myoblasts, and selectively associates with kinesins Kif1bα and Kif1c through its zinc finger (ZnF) domains. Other RBPs with similar ZnFs associate with these kinesins, implicating a motor-RBP specificity code. MBNL and kinesin perturbation leads to widespread mRNA mis-localization, including depletion of Nucleolin transcripts from neurites. Live cell imaging and fractionation reveal that the unstructured carboxy-terminal tail of MBNL1 allows for anchoring at membranes. An approach, termed RBP Module Recruitment and Imaging (RBP-MRI), reconstitutes kinesin- and membrane-recruitment functions using MBNL-MS2 coat protein fusions. Our findings decouple kinesin association, RNA binding, and membrane anchoring functions of MBNL while establishing general strategies for studying multi-functional, modular domains of RBPs.
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Affiliation(s)
- Ryan P Hildebrandt
- Department of Molecular Genetics & Microbiology, Center for Neurogenetics, Genetics Institute, University of Florida, Gainesville, FL, USA
| | - Kathryn R Moss
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, USA
| | | | - Luke A Knudson
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, USA
| | - Lance T Denes
- Department of Molecular Genetics & Microbiology, Center for Neurogenetics, Genetics Institute, University of Florida, Gainesville, FL, USA
| | - Tanvi Saxena
- Department of Molecular Genetics & Microbiology, Center for Neurogenetics, Genetics Institute, University of Florida, Gainesville, FL, USA
| | - Devi Prasad Boggupalli
- Department of Molecular Genetics & Microbiology, Center for Neurogenetics, Genetics Institute, University of Florida, Gainesville, FL, USA
| | - Zhuangyue Li
- Department of Molecular Genetics & Microbiology, Center for Neurogenetics, Genetics Institute, University of Florida, Gainesville, FL, USA
| | - Kun Lin
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, USA
| | - Gary J Bassell
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, USA.
| | - Eric T Wang
- Department of Molecular Genetics & Microbiology, Center for Neurogenetics, Genetics Institute, University of Florida, Gainesville, FL, USA.
- Myology Institute, University of Florida, Gainesville, FL, USA.
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4
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Scott H, Dong L, Stevenson A, MacDonald AI, Srinivasan S, Massimi P, Banks L, Martin PE, Johnstone SR, Graham SV. The human discs large protein 1 interacts with and maintains connexin 43 at the plasma membrane in keratinocytes. J Cell Sci 2023; 136:jcs259984. [PMID: 37288673 PMCID: PMC10309592 DOI: 10.1242/jcs.259984] [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: 03/08/2022] [Accepted: 04/21/2023] [Indexed: 05/10/2023] Open
Abstract
Gap junction channels, composed of connexins, allow direct cell-to-cell communication. Connexin 43 (Cx43; also known as GJA1) is widely expressed in tissues, including the epidermis. In a previous study of human papillomavirus-positive cervical epithelial tumour cells, we identified Cx43 as a binding partner of the human homologue of Drosophila Discs large (Dlg1; also known as SAP97). Dlg1 is a member of the membrane associated-guanylate kinase (MAGUK) scaffolding protein family, which is known to control cell shape and polarity. Here, we show that Cx43 also interacts with Dlg1 in uninfected keratinocytes in vitro and in keratinocytes, dermal cells and adipocytes in normal human epidermis in vivo. Depletion of Dlg1 in keratinocytes did not alter Cx43 transcription but was associated with a reduction in Cx43 protein levels. Reduced Dlg1 levels in keratinocytes resulted in a reduction in Cx43 at the plasma membrane with a concomitant reduction in gap junctional intercellular communication and relocation of Cx43 to the Golgi compartment. Our data suggest a key role for Dlg1 in maintaining Cx43 at the plasma membrane in keratinocytes.
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Affiliation(s)
- Harry Scott
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow G61 1QH, UK
| | - Li Dong
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow G61 1QH, UK
| | - Andrew Stevenson
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow G61 1QH, UK
| | - Alasdair I. MacDonald
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow G61 1QH, UK
| | - Sharmila Srinivasan
- Translation Research Platform for Veterinary Biologicals, Chennai, Tamil Nadu, India
| | - Paola Massimi
- International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Lawrence Banks
- International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Patricia E. Martin
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, UK
| | - Scott R. Johnstone
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Center for Vascular and Heart Research, Virginia Tech, Roanoke VA 24016, USA
| | - Sheila V. Graham
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow G61 1QH, UK
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5
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Veljačić Visković D, Lozić M, Vukoja M, Šoljić V, Vukojević K, Glavina Durdov M, Filipović N, Lozić B. Spatio-Temporal Expression Pattern of CAKUT Candidate Genes DLG1 and KIF12 during Human Kidney Development. Biomolecules 2023; 13:biom13020340. [PMID: 36830709 PMCID: PMC9953652 DOI: 10.3390/biom13020340] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/05/2023] [Accepted: 02/08/2023] [Indexed: 02/12/2023] Open
Abstract
We aimed to investigate expression of the novel susceptibility genes for CAKUT, DLG1 and KIF12, proposed by a systematic in silico approach, in developing and postnatal healthy human kidneys to provide information about their spatiotemporal expression pattern. We analyzed expression of their protein products by immunohistochemistry and immunofluorescence and quantified relative mRNA levels by RT-qPCR. Statistically significant differences in expression patterns were observed between certain developmental stages. Strong expression of DLG1 was observed in the developing kidney, with a gradual decrease from the first phase of kidney development (Ph1) until the third phase (Ph3), when most nephrons are formed; at later stages, the highest expression was observed in the tubules. KIF12 was highly expressed in the developing structures, especially in Ph1, with a gradual decrease until the postnatal phase, which would indicate a significant role in nephrogenesis. Co-localization of DLG1 and KIF12 was pronounced in Ph1, especially on the apical side of the tubular epithelial cells. Thereafter, their expression gradually became weaker and was only visible as punctate staining in Ph4. The direct association of DLG1 with KIF12 as control genes of normal kidney development may reveal their new functional aspect in renal tubular epithelial cells.
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Affiliation(s)
| | - Mirela Lozić
- Department of Anatomy, Histology and Embryology, University of Split School of Medicine, Šoltanska 2, 21 000 Split, Croatia
- Correspondence: ; Tel.: +385-21-557-800
| | - Martina Vukoja
- Laboratory of Morphology, Department of Histology and Embryology, School of Medicine, University of Mostar, 88 000 Mostar, Bosnia and Herzegovina
| | - Violeta Šoljić
- Laboratory of Morphology, Department of Histology and Embryology, School of Medicine, University of Mostar, 88 000 Mostar, Bosnia and Herzegovina
- Faculty of Health Studies, University of Mostar, 88 000 Mostar, Bosnia and Herzegovina
| | - Katarina Vukojević
- Department of Anatomy, Histology and Embryology, University of Split School of Medicine, Šoltanska 2, 21 000 Split, Croatia
- Laboratory of Morphology, Department of Histology and Embryology, School of Medicine, University of Mostar, 88 000 Mostar, Bosnia and Herzegovina
- Faculty of Health Studies, University of Mostar, 88 000 Mostar, Bosnia and Herzegovina
- Department of Anatomy, University of Mostar, 88 000 Mostar, Bosnia and Herzegovina
- Center for Translational Research in Biomedicine, University of Split School of Medicine, 21 000 Split, Croatia
| | - Merica Glavina Durdov
- Department of Pathology, University Hospital Split, 21 000 Split, Croatia
- School of Medicine, University of Split, Šoltanska 2, 21 000 Split, Croatia
| | - Natalija Filipović
- Department of Anatomy, Histology and Embryology, University of Split School of Medicine, Šoltanska 2, 21 000 Split, Croatia
- Department of Anatomy, University of Mostar, 88 000 Mostar, Bosnia and Herzegovina
- Center for Translational Research in Biomedicine, University of Split School of Medicine, 21 000 Split, Croatia
| | - Bernarda Lozić
- Paediatric Diseases Department, University Hospital of Split, Spinčićeva 1, 21 000 Split, Croatia
- School of Medicine, University of Split, Šoltanska 2, 21 000 Split, Croatia
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6
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Soppina P, Patel N, Shewale DJ, Rai A, Sivaramakrishnan S, Naik PK, Soppina V. Kinesin-3 motors are fine-tuned at the molecular level to endow distinct mechanical outputs. BMC Biol 2022; 20:177. [PMID: 35948971 PMCID: PMC9364601 DOI: 10.1186/s12915-022-01370-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Accepted: 07/06/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Kinesin-3 family motors drive diverse cellular processes and have significant clinical importance. The ATPase cycle is integral to the processive motility of kinesin motors to drive long-distance intracellular transport. Our previous work has demonstrated that kinesin-3 motors are fast and superprocessive with high microtubule affinity. However, chemomechanics of these motors remain poorly understood. RESULTS We purified kinesin-3 motors using the Sf9-baculovirus expression system and demonstrated that their motility properties are on par with the motors expressed in mammalian cells. Using biochemical analysis, we show for the first time that kinesin-3 motors exhibited high ATP turnover rates, which is 1.3- to threefold higher compared to the well-studied kinesin-1 motor. Remarkably, these ATPase rates correlate to their stepping rate, suggesting a tight coupling between chemical and mechanical cycles. Intriguingly, kinesin-3 velocities (KIF1A > KIF13A > KIF13B > KIF16B) show an inverse correlation with their microtubule-binding affinities (KIF1A < KIF13A < KIF13B < KIF16B). We demonstrate that this differential microtubule-binding affinity is largely contributed by the positively charged residues in loop8 of the kinesin-3 motor domain. Furthermore, microtubule gliding and cellular expression studies displayed significant microtubule bending that is influenced by the positively charged insert in the motor domain, K-loop, a hallmark of kinesin-3 family. CONCLUSIONS Together, we propose that a fine balance between the rate of ATP hydrolysis and microtubule affinity endows kinesin-3 motors with distinct mechanical outputs. The K-loop, a positively charged insert in the loop12 of the kinesin-3 motor domain promotes microtubule bending, an interesting phenomenon often observed in cells, which requires further investigation to understand its cellular and physiological significance.
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Affiliation(s)
- Pushpanjali Soppina
- Discipline of Biological Engineering, Indian Institute of Technology Gandhinagar, Gandhinagar, Gujarat, 382355, India.,Department of Biotechnology and Bioinformatics, Sambalpur University, Sambalpur, Orissa, 768019, India
| | - Nishaben Patel
- Discipline of Biological Engineering, Indian Institute of Technology Gandhinagar, Gandhinagar, Gujarat, 382355, India.,Department of Genetics, Cell Biology and Development, University of Minnesota, Minnesota, MN, 55455, USA
| | - Dipeshwari J Shewale
- Discipline of Biological Engineering, Indian Institute of Technology Gandhinagar, Gandhinagar, Gujarat, 382355, India
| | - Ashim Rai
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minnesota, MN, 55455, USA
| | - Sivaraj Sivaramakrishnan
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minnesota, MN, 55455, USA
| | - Pradeep K Naik
- Department of Biotechnology and Bioinformatics, Sambalpur University, Sambalpur, Orissa, 768019, India
| | - Virupakshi Soppina
- Discipline of Biological Engineering, Indian Institute of Technology Gandhinagar, Gandhinagar, Gujarat, 382355, India.
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7
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Morthorst SK, Nielsen C, Farinelli P, Anvarian Z, Rasmussen CBR, Serra-Marques A, Grigoriev I, Altelaar M, Fürstenberg N, Ludwig A, Akhmanova A, Christensen ST, Pedersen LB. Angiomotin isoform 2 promotes binding of PALS1 to KIF13B at primary cilia and regulates ciliary length and signaling. J Cell Sci 2022; 135:275635. [PMID: 35673984 DOI: 10.1242/jcs.259471] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 05/16/2022] [Indexed: 11/20/2022] Open
Abstract
The kinesin-3 motor KIF13B functions in endocytosis, vesicle transport and regulation of ciliary length and signaling. Direct binding of the membrane-associated guanylate kinase (MAGUK) DLG1 to the MAGUK-binding stalk domain of KIF13B relieves motor autoinhibition and promotes microtubule plus-end-directed cargo transport. Here, we characterize angiomotin (AMOT) isoform 2 (p80, referred to as Ap80) as a novel KIF13B interactor that promotes binding of another MAGUK, the polarity protein and Crumbs complex component PALS1, to KIF13B. Live-cell imaging analysis indicated that Ap80 is concentrated at and recruits PALS1 to the base of the primary cilium, but is not a cargo of KIF13B itself. Consistent with a ciliary function for Ap80, its depletion led to elongated primary cilia and reduced agonist-induced ciliary accumulation of SMO, a key component of the Hedgehog signaling pathway, whereas Ap80 overexpression caused ciliary shortening. Our results suggest that Ap80 activates KIF13B cargo binding at the base of the primary cilium to regulate ciliary length, composition and signaling.
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Affiliation(s)
- Stine Kjær Morthorst
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark
| | - Camilla Nielsen
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark
| | - Pietro Farinelli
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark
| | - Zeinab Anvarian
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark
| | | | - Andrea Serra-Marques
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Ilya Grigoriev
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Maarten Altelaar
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Nicoline Fürstenberg
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark
| | - Alexander Ludwig
- School of Biological Sciences and NTU Institute of Structural Biology, Nanyang Technological University, Singapore City 637551, Singapore
| | - Anna Akhmanova
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Søren Tvorup Christensen
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark
| | - Lotte Bang Pedersen
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark
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8
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Kumari D, Ray K. Phosphoregulation of Kinesins Involved in Long-Range Intracellular Transport. Front Cell Dev Biol 2022; 10:873164. [PMID: 35721476 PMCID: PMC9203973 DOI: 10.3389/fcell.2022.873164] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 04/29/2022] [Indexed: 12/28/2022] Open
Abstract
Kinesins, the microtubule-dependent mechanochemical enzymes, power a variety of intracellular movements. Regulation of Kinesin activity and Kinesin-Cargo interactions determine the direction, timing and flux of various intracellular transports. This review examines how phosphorylation of Kinesin subunits and adaptors influence the traffic driven by Kinesin-1, -2, and -3 family motors. Each family of Kinesins are phosphorylated by a partially overlapping set of serine/threonine kinases, and each event produces a unique outcome. For example, phosphorylation of the motor domain inhibits motility, and that of the stalk and tail domains induces cargo loading and unloading effects according to the residue and context. Also, the association of accessory subunits with cargo and adaptor proteins with the motor, respectively, is disrupted by phosphorylation. In some instances, phosphorylation by the same kinase on different Kinesins elicited opposite outcomes. We discuss how this diverse range of effects could manage the logistics of Kinesin-dependent, long-range intracellular transport.
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9
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Juhl AD, Anvarian Z, Kuhns S, Berges J, Andersen JS, Wüstner D, Pedersen LB. Transient accumulation and bidirectional movement of KIF13B in primary cilia. J Cell Sci 2022; 136:275012. [DOI: 10.1242/jcs.259257] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 04/01/2022] [Indexed: 10/18/2022] Open
Abstract
Primary cilia are microtubule-based sensory organelles whose assembly and function rely on the conserved bidirectional intraflagellar transport (IFT) system, which is powered by anterograde kinesin-2 and retrograde cytoplasmic dynein 2 motors. Nematodes additionally employ a cell type-specific kinesin-3 motor, KLP-6, which moves within cilia independently of IFT and regulates ciliary content and function. Here we provide evidence that a KLP-6 homolog, KIF13B, undergoes bursts of bidirectional movement within primary cilia of cultured immortalized human retinal pigment epithelial (hTERT-RPE1) cells. Anterograde and retrograde intraciliary velocities of KIF13B were similar to those of IFT (IFT172-eGFP), but intraciliary movement of KIF13B required its own motor domain and appeared to be cell-type specific. Our work provides the first demonstration of motor-driven, intraciliary movement by a vertebrate kinesin other than kinesin-2 motors.
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Affiliation(s)
- Alice Dupont Juhl
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Zeinab Anvarian
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark
| | - Stefanie Kuhns
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Julia Berges
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark
- Department of Biomedicine, Facultad Ciencias Experimentales, Universidad Francisco de Vitoria, Ctra. Pozuelo-Majadahonda Km. 1.800, 28223 Pozuelo de Alarcón (Madrid), Spain
| | - Jens S. Andersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Daniel Wüstner
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Lotte B. Pedersen
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark
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10
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Emura N, Yajima M. Micromere formation and its evolutionary implications in the sea urchin. Curr Top Dev Biol 2021; 146:211-238. [PMID: 35152984 PMCID: PMC8868499 DOI: 10.1016/bs.ctdb.2021.10.008] [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: 01/03/2023]
Abstract
The micromeres of the sea urchin embryo are distinct from other blastomeres. After they arise through an asymmetric cell division at the 8- to 16-cell stage, micromeres immediately function as organizers. They also commit themselves to specific cell fates such as larval skeletogenic cells and primordial germ cells, while other blastomeres remain plastic and uncommitted at the 16-cell stage. In the phylum Echinodermata, only the sea urchin (class Echinoidea) embryo forms micromeres that serve as apparent organizers during early embryogenesis. Therefore, it is considered that micromeres are the derived features and that modification(s) of the developmental system allowed evolutionary introduction of this unique cell lineage. In this chapter, we summarize the both historic and recent observations that demonstrate unique properties of micromeres and discuss how this lineage of micromeres may have arisen during echinoderm evolution.
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Affiliation(s)
- Natsuko Emura
- Department of Molecular Biology Cell Biology Biochemistry, Brown University, Providence, RI, United States
| | - Mamiko Yajima
- Department of Molecular Biology Cell Biology Biochemistry, Brown University, Providence, RI, United States.
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11
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Wavreil FDM, Yajima M. Diversity of activator of G-protein signaling (AGS)-family proteins and their impact on asymmetric cell division across taxa. Dev Biol 2020; 465:89-99. [PMID: 32687894 DOI: 10.1016/j.ydbio.2020.07.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/05/2020] [Accepted: 07/06/2020] [Indexed: 11/18/2022]
Abstract
Asymmetric cell division (ACD) is a cellular process that forms two different cell types through a cell division and is thus critical for the development of all multicellular organisms. Not all but many of the ACD processes are mediated by proper orientation of the mitotic spindle, which segregates the fate determinants asymmetrically into daughter cells. In many cell types, the evolutionarily conserved protein complex of Gαi/AGS-family protein/NuMA-like protein appears to play critical roles in orienting the spindle and/or generating the polarized cortical forces to regulate ACD. Studies in various organisms reveal that this conserved protein complex is slightly modified in each phylum or even within species. In particular, AGS-family proteins appear to be modified with a variable number of motifs in their functional domains across taxa. This apparently creates different molecular interactions and mechanisms of ACD in each developmental program, ultimately contributing to developmental diversity across species. In this review, we discuss how a conserved ACD machinery has been modified in each phylum over the course of evolution with a major focus on the molecular evolution of AGS-family proteins and its impact on ACD regulation.
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Affiliation(s)
- Florence D M Wavreil
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, 02906, USA
| | - Mamiko Yajima
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, 02906, USA.
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12
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Yoo KS, Lee K, Oh JY, Lee H, Park H, Park YS, Kim HK. Postsynaptic density protein 95 (PSD-95) is transported by KIF5 to dendritic regions. Mol Brain 2019; 12:97. [PMID: 31753031 PMCID: PMC6873588 DOI: 10.1186/s13041-019-0520-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 11/04/2019] [Indexed: 11/18/2022] Open
Abstract
Postsynaptic density protein 95 (PSD-95) is a pivotal postsynaptic scaffolding protein in excitatory neurons. Although the transport and regulation of PSD-95 in synaptic regions is well understood, dendritic transport of PSD-95 before synaptic localization still remains to be clarified. To evaluate the role of KIF5, conventional kinesin, in the dendritic transport of PSD-95 protein, we expressed a transport defective form of KIF5A (ΔMD) that does not contain the N-terminal motor domain. Expression of ΔMD significantly decreased PSD-95 level in the dendrites. Consistently, KIF5 was associated with PSD-95 in in vitro and in vivo assays. This interaction was mediated by the C-terminal tail regions of KIF5A and the third PDZ domain of PSD-95. Additionally, the ADPDZ3 (the association domain of NMDA receptor and PDZ3 domain) expression significantly reduced the levels of PSD-95, glutamate receptor 1 (GluA1) in dendrites. The association between PSD-95 and KIF5A was dose-dependent on Staufen protein, suggesting that the Staufen plays a role as a regulatory role in the association. Taken together, our data suggest a new mechanism for dendritic transport of the AMPA receptor-PSD-95.
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Affiliation(s)
- Ki-Seo Yoo
- Department of Medicine and Microbiology, Graduate Program in Neuroscience, College of Medicine, Chungbuk National University, 1 Chungdae-ro, Seowon-gu, Cheongju, 28644, South Korea
| | - Kina Lee
- Department of Medicine and Microbiology, Graduate Program in Neuroscience, College of Medicine, Chungbuk National University, 1 Chungdae-ro, Seowon-gu, Cheongju, 28644, South Korea
| | - Jun-Young Oh
- Department of Medicine and Microbiology, Graduate Program in Neuroscience, College of Medicine, Chungbuk National University, 1 Chungdae-ro, Seowon-gu, Cheongju, 28644, South Korea.,Department of Structure and Function of Neural Network, Korea Brain Research Institute, 61 Cheomdan-ro, Dong-gu, Daegu, 41068, South Korea
| | - Hyoeun Lee
- Department of Structure and Function of Neural Network, Korea Brain Research Institute, 61 Cheomdan-ro, Dong-gu, Daegu, 41068, South Korea
| | - Hyungju Park
- Department of Structure and Function of Neural Network, Korea Brain Research Institute, 61 Cheomdan-ro, Dong-gu, Daegu, 41068, South Korea
| | - Young Seok Park
- Department of Neurosurgery, Graduate Program in Neuroscience, College of Medicine, Chungbuk National University, 1 Chungdae-ro, Seowon-gu, Cheongju, 28644, South Korea
| | - Hyong Kyu Kim
- Department of Medicine and Microbiology, Graduate Program in Neuroscience, College of Medicine, Chungbuk National University, 1 Chungdae-ro, Seowon-gu, Cheongju, 28644, South Korea.
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Abstract
Asymmetric cell division (ACD) is a conserved strategy for achieving cell diversity. A cell can undergo an intrinsic ACD through asymmetric segregation of cell fate determinants or cellular organelles. Recently, a new biophysical concept known as biomolecular phase separation, through which proteins and/or RNAs autonomously form a highly concentrated non-membrane-enclosed compartment via multivalent interactions, has provided new insights into the assembly and regulation of many membrane-less or membrane-attached organelles. Intriguingly, biomolecular phase separation is suggested to drive asymmetric condensation of cell fate determinants during ACD as well as organization of cellular organelles involved in ACD. In this Perspective, I first summarize recent findings on the molecular basis governing intrinsic ACD. Then I will discuss how ACD might be regulated by formation of dense molecular assemblies via phase separation.
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Affiliation(s)
- Wenyu Wen
- Department of Neurosurgery, Huashan Hospital, Institutes of Biomedical Sciences, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences , Shanghai Medical College of Fudan University , Shanghai 200032 , China
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14
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Mills J, Hanada T, Hase Y, Liscum L, Chishti AH. LDL receptor related protein 1 requires the I 3 domain of discs-large homolog 1/DLG1 for interaction with the kinesin motor protein KIF13B. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2019; 1866:118552. [PMID: 31487503 DOI: 10.1016/j.bbamcr.2019.118552] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 07/25/2019] [Accepted: 08/12/2019] [Indexed: 01/01/2023]
Abstract
KIF13B, a kinesin-3 family motor, was originally identified as GAKIN due to its biochemical interaction with human homolog of Drosophila discs-large tumor suppressor (hDLG1). Unlike its homolog KIF13A, KIF13B contains a carboxyl-terminal CAP-Gly domain. To investigate the function of the CAP-Gly domain, we developed a mouse model that expresses a truncated form of KIF13B protein lacking its CAP-Gly domain (KIF13BΔCG), whereas a second mouse model lacks the full-length KIF13A. Here we show that the KIF13BΔCG mice exhibit relatively higher serum cholesterol consistent with the reduced uptake of [3H]CO-LDL in KIF13BΔCG mouse embryo fibroblasts. The plasma level of factor VIII was not significantly elevated in the KIF13BΔCG mice, suggesting that the CAP-Gly domain region of KIF13B selectively regulates LRP1-mediated lipoprotein endocytosis. No elevation of either serum cholesterol or plasma factor VIII was observed in the full length KIF13A null mouse model. The deletion of the CAP-Gly domain region caused subcellular mislocalization of truncated KIF13B concomitant with the mislocalization of LRP1. Mechanistically, the cytoplasmic domain of LRP1 interacts specifically with the alternatively spliced I3 domain of DLG1, which complexes with KIF13B via their GUK-MBS domains, respectively. Importantly, double mutant mice generated by crossing KIF13A null and KIF13BΔCG mice suffer from perinatal lethality showing potential craniofacial defects. Together, this study provides first evidence that the carboxyl-terminal region of KIF13B containing the CAP-Gly domain is important for the LRP1-DLG1-KIF13B complex formation with implications in the regulation of metabolism, cell polarity, and development.
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Affiliation(s)
- Joslyn Mills
- Graduate Program in Cellular and Molecular Physiology, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine, Boston, MA, USA
| | - Toshihiko Hanada
- Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA, USA
| | - Yoichi Hase
- Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA, USA
| | - Laura Liscum
- Graduate Program in Cellular and Molecular Physiology, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine, Boston, MA, USA; Department of Immunology, Tufts University School of Medicine, Boston, MA, USA
| | - Athar H Chishti
- Graduate Program in Cellular and Molecular Physiology, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine, Boston, MA, USA; Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA, USA.
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15
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Magaletta ME, Perkins KJ, Deuchler CP, Pieczynski JN. The Kinesin-3 motor, KLP-4, mediates axonal organization and cholinergic signaling in Caenorhabditis elegans. FASEB Bioadv 2019; 1:450-460. [PMID: 32123843 PMCID: PMC6996341 DOI: 10.1096/fba.2019-00019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/28/2019] [Indexed: 12/12/2022] Open
Abstract
Microtubule plus-end directed trafficking is dominated by kinesin motors, yet kinesins differ in terms of cargo identity, movement rate, and distance travelled. Functional diversity of kinesins is especially apparent in polarized neurons, where long distance trafficking is required for efficient signal transduction-behavioral response paradigms. The Kinesin-3 superfamily are expressed in neurons and are hypothesized to have significant roles in neuronal signal transduction due to their high processivity. Although much is known about Kinesin-3 motors mechanistically in vitro, there is little known about their mechanisms in vivo. Here, we analyzed KLP-4, the Caenorhabditis elegans homologue of human KIF13A and KIF13B. Like other Kinesin-3 superfamily motors, klp-4 is highly expressed in the ventral nerve cord command interneurons of the animal, suggesting it might have a role in controlling movement of the animal. We characterized an allele of klp-4 that contains are large indel in the cargo binding domain of the motor, however, the gene still appears to be expressed. Behavioral analysis demonstrated that klp-4 mutants have defects in locomotive signaling, but not the strikingly uncoordinated movements such as those found in unc-104/KIF1A mutants. Animals with this large deletion are hypersensitive to the acetylcholinesterase inhibitor aldicarb but are unaffected by exogenous serotonin. Interestingly, this large klp-4 indel does not affect gross neuronal development but does lead to aggregation and disorganization of RAB-3 at synapses. Taken together, these data suggest a role for KLP-4 in modulation of cholinergic signaling in vivo and shed light on possible in vivo mechanisms of Kinesin-3 motor regulation.
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Affiliation(s)
- Margaret E. Magaletta
- Department of BiologyRollins CollegeWinter ParkFlorida
- Program in Molecular Medicine, Diabetes Center of ExcellenceUniversity of Massachusetts Medical SchoolWorcesterMassachusetts
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16
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Morthorst SK, Christensen ST, Pedersen LB. Regulation of ciliary membrane protein trafficking and signalling by kinesin motor proteins. FEBS J 2018; 285:4535-4564. [PMID: 29894023 DOI: 10.1111/febs.14583] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/09/2018] [Accepted: 06/11/2018] [Indexed: 12/14/2022]
Abstract
Primary cilia are antenna-like sensory organelles that regulate a substantial number of cellular signalling pathways in vertebrates, both during embryonic development as well as in adulthood, and mutations in genes coding for ciliary proteins are causative of an expanding group of pleiotropic diseases known as ciliopathies. Cilia consist of a microtubule-based axoneme core, which is subtended by a basal body and covered by a bilayer lipid membrane of unique protein and lipid composition. Cilia are dynamic organelles, and the ability of cells to regulate ciliary protein and lipid content in response to specific cellular and environmental cues is crucial for balancing ciliary signalling output. Here we discuss mechanisms involved in regulation of ciliary membrane protein trafficking and signalling, with main focus on kinesin-2 and kinesin-3 family members.
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17
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Kreitzer G, Myat MM. Microtubule Motors in Establishment of Epithelial Cell Polarity. Cold Spring Harb Perspect Biol 2018; 10:cshperspect.a027896. [PMID: 28264820 DOI: 10.1101/cshperspect.a027896] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Epithelial cells play a key role in insuring physiological homeostasis by acting as a barrier between the outside environment and internal organs. They are also responsible for the vectorial transport of ions and fluid essential to the function of many organs. To accomplish these tasks, epithelial cells must generate an asymmetrically organized plasma membrane comprised of structurally and functionally distinct apical and basolateral membranes. Adherent and occluding junctions, respectively, anchor cells within a layer and prevent lateral diffusion of proteins in the outer leaflet of the plasma membrane and restrict passage of proteins and solutes through intercellular spaces. At a fundamental level, the establishment and maintenance of epithelial polarity requires that signals initiated at cell-substratum and cell-cell adhesions are transmitted appropriately and dynamically to the cytoskeleton, to the membrane-trafficking machinery, and to the regulation of occluding and adherent junctions. Rigorous descriptive and mechanistic studies published over the last 50 years have provided great detail to our understanding of epithelial polarization. Yet still, critical early steps in morphogenesis are not yet fully appreciated. In this review, we discuss how cytoskeletal motor proteins, primarily kinesins, contribute to coordinated modification of microtubule and actin arrays, formation and remodeling of cell adhesions to targeted membrane trafficking, and to initiating the formation and expansion of an apical lumen.
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Affiliation(s)
- Geri Kreitzer
- Department of Pathobiology, Sophie Davis School of Biomedical Education, City College of New York, The City University of New York School of Medicine, New York, New York 10031
| | - Monn Monn Myat
- Department of Biology, Medgar Evers College, Brooklyn, New York 11225.,The Graduate Center, The City University of New York, New York, New York 10016
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18
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Wen W, Zhang M. Protein Complex Assemblies in Epithelial Cell Polarity and Asymmetric Cell Division. J Mol Biol 2017; 430:3504-3520. [PMID: 28963071 DOI: 10.1016/j.jmb.2017.09.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/16/2017] [Accepted: 09/19/2017] [Indexed: 12/24/2022]
Abstract
Asymmetric local concentration of protein complexes on distinct membrane regions is a fundamental property in numerous biological processes and is a hallmark of cell polarity. Evolutionarily conserved core polarity proteins form specific and dynamic networks to regulate the establishment and maintenance of cell polarity, as well as distinct polarity-driven cellular events. This review focuses on the molecular and structural basis governing regulated formation of several sets of core cell polarity regulatory complexes, as well as their functions in epithelial cell polarization and asymmetric cell division.
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Affiliation(s)
- Wenyu Wen
- Department of Neurosurgery, Huashan Hospital, Institutes of Biomedical Sciences, Fudan University, Shanghai 200040, China; Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Systems Biology for Medicine, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, PR China.
| | - Mingjie Zhang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; Center of Systems Biology and Human Health, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
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19
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Gomes ER, Cadot B. Molecular motors and nuclear movements in muscle. Commun Integr Biol 2017. [PMCID: PMC5501210 DOI: 10.1080/19420889.2017.1319537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Muscle fibers have the particularity of containing numerous nuclei evenly distributed and positioned next to the plasma membrane. This unique disposition is the result of sequential events of nuclear movements that start when myoblasts fuse together and end with the clustering of few nuclei under the neuromuscular junction. Nuclei are mispositioned in multiple muscle disorders therefore the mechanisms of nuclear positioning can be novel targets for muscle disorders therapies. The 2 first nuclear movements that occur upon myoblast fusion require different microtubule motors. We performed a siRNA screen against all the microtubules motors and quantified nuclei behavior after fusion and inside the myotube. The different motors we found to be involved in the nuclear behaviors and the analysis of motors expression suggest a competition between both movement mechanisms, which potentially relies on the discrepancy between myoblast and myotube microtubules stability.
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Affiliation(s)
- E. R. Gomes
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Lisboa, Portugal
| | - B. Cadot
- Center of Research in Myology, INSERM UPMC UMR974, CNRS FRE3617, Paris, France
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20
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Bergstralh DT, Dawney NS, St Johnston D. Spindle orientation: a question of complex positioning. Development 2017; 144:1137-1145. [DOI: 10.1242/dev.140764] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The direction in which a cell divides is determined by the orientation of its mitotic spindle at metaphase. Spindle orientation is therefore important for a wide range of developmental processes, ranging from germline stem cell division to epithelial tissue homeostasis and regeneration. In multiple cell types in multiple animals, spindle orientation is controlled by a conserved biological machine that mediates a pulling force on astral microtubules. Restricting the localization of this machine to only specific regions of the cortex can thus determine how the mitotic spindle is oriented. As we review here, recent findings based on studies in tunicate, worm, fly and vertebrate cells have revealed that the mechanisms for mediating this restriction are surprisingly diverse.
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Affiliation(s)
- Dan T. Bergstralh
- Department of Biology, University of Rochester, Rochester, NY 14627, USA
| | - Nicole S. Dawney
- Department of Biology, University of Rochester, Rochester, NY 14627, USA
| | - Daniel St Johnston
- The Gurdon Institute and the Department of Genetics, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
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21
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KIF13B establishes a CAV1-enriched microdomain at the ciliary transition zone to promote Sonic hedgehog signalling. Nat Commun 2017; 8:14177. [PMID: 28134340 PMCID: PMC5290278 DOI: 10.1038/ncomms14177] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 12/06/2016] [Indexed: 12/20/2022] Open
Abstract
Ciliary membrane composition is controlled by transition zone (TZ) proteins such as RPGRIP1, RPGRIPL and NPHP4, which are vital for balanced coordination of diverse signalling systems like the Sonic hedgehog (Shh) pathway. Activation of this pathway involves Shh-induced ciliary accumulation of Smoothened (SMO), which is disrupted by disease-causing mutations in TZ components. Here we identify kinesin-3 motor protein KIF13B as a novel member of the RPGRIP1N-C2 domain-containing protein family and show that KIF13B regulates TZ membrane composition and ciliary SMO accumulation. KIF13B is upregulated during ciliogenesis and is recruited to the ciliary base by NPHP4, which binds to two distinct sites in the KIF13B tail region, including an RPGRIP1N-C2 domain. KIF13B and NPHP4 are both essential for establishment of a CAV1 membrane microdomain at the TZ, which in turn is required for Shh-induced ciliary SMO accumulation. Thus KIF13B is a novel regulator of ciliary TZ configuration, membrane composition and Shh signalling.
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22
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An Atypical MAGUK GK Target Recognition Mode Revealed by the Interaction between DLG and KIF13B. Structure 2016; 24:1876-1885. [PMID: 27642159 DOI: 10.1016/j.str.2016.08.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Revised: 07/14/2016] [Accepted: 08/04/2016] [Indexed: 01/19/2023]
Abstract
The membrane-associated guanylate kinase (MAGUK) scaffold proteins share a signature guanylate kinase (GK) domain. Despite their diverse functional roles in cell polarity control and synaptic signaling, the currently known mode of action of MAGUK GK is via its binding to phosphorylated short peptides from target proteins. Here, we discover that the GK domain of DLG MAGUK binds to an unphosphorylated and autonomously folded domain within the stalk region (MAGUK binding stalk [MBS] domain) of a kinesin motor KIF13B with high specificity and affinity. The structure of DLG4 GK in complex with KIF13B MBS reveals the molecular mechanism governing this atypical GK/target recognition mode and provides insights into DLG/KIF13B complex-mediated regulation of diverse cellular processes such as asymmetric cell division. We further show that binding to non-phosphorylated targets is another general property of MAGUK GKs, thus expanding the mechanisms of action of the MAGUK family proteins.
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23
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Wu GH, Muthaiyan Shanmugam M, Bhan P, Huang YH, Wagner OI. Identification and Characterization of LIN-2(CASK) as a Regulator of Kinesin-3 UNC-104(KIF1A) Motility and Clustering in Neurons. Traffic 2016; 17:891-907. [PMID: 27172328 DOI: 10.1111/tra.12413] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 05/09/2016] [Accepted: 05/09/2016] [Indexed: 12/20/2022]
Abstract
Kinesin-3 UNC-104(KIF1A) is the major axonal transporter of synaptic vesicles. Employing yeast two-hybrid and co-immunoprecipitation (Co-IP) assays, we characterized a LIN-2(CASK) binding site overlapping with that of reported UNC-104 activator protein SYD-2(Liprin-α) on the motor's stalk domain. We identified the L27 and GUK domains of LIN-2 to be the most critical interaction domains for UNC-104. Further, we demonstrated that the L27 domain interacts with the sterile alpha motifs (SAM) domains of SYD-2, while the GUK domain is able to interact with both the coiled coils and SAM domains of SYD-2. LIN-2 and SYD-2 colocalize in Caenorhabditis elegans neurons and display interactions in bimolecular fluorescence complementation (BiFC) assays. UNC-104 motor motility and Synaptobrevin-1 (SNB-1) cargo transport are largely diminished in neurons of LIN-2 knockout worms, which cannot be compensated by overexpressing SYD-2. The absence of the motor-activating function of LIN-2 results in increased motor clustering along axons, thus retaining SNB-1 cargo in cell bodies. LIN-2 and SYD-2 both positively affect the velocity of UNC-104, however, only LIN-2 is able to efficiently elevate the motor's run lengths. From our study, we conclude that LIN-2 and SYD-2 act in a functional complex to regulate the motor with LIN-2 being the more prominent activator.
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Affiliation(s)
- Gong-Her Wu
- Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu 30013, Taiwan (ROC)
| | - Muniesh Muthaiyan Shanmugam
- Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu 30013, Taiwan (ROC)
| | - Prerana Bhan
- Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu 30013, Taiwan (ROC)
| | - Yu-Hsin Huang
- Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu 30013, Taiwan (ROC)
| | - Oliver Ingvar Wagner
- Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu 30013, Taiwan (ROC)
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24
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Noseda R, Guerrero-Valero M, Alberizzi V, Previtali SC, Sherman DL, Palmisano M, Huganir RL, Nave KA, Cuenda A, Feltri ML, Brophy PJ, Bolino A. Kif13b Regulates PNS and CNS Myelination through the Dlg1 Scaffold. PLoS Biol 2016; 14:e1002440. [PMID: 27070899 PMCID: PMC4829179 DOI: 10.1371/journal.pbio.1002440] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 03/16/2016] [Indexed: 12/03/2022] Open
Abstract
Microtubule-based kinesin motors have many cellular functions, including the transport of a variety of cargos. However, unconventional roles have recently emerged, and kinesins have also been reported to act as scaffolding proteins and signaling molecules. In this work, we further extend the notion of unconventional functions for kinesin motor proteins, and we propose that Kif13b kinesin acts as a signaling molecule regulating peripheral nervous system (PNS) and central nervous system (CNS) myelination. In this process, positive and negative signals must be tightly coordinated in time and space to orchestrate myelin biogenesis. Here, we report that in Schwann cells Kif13b positively regulates myelination by promoting p38γ mitogen-activated protein kinase (MAPK)-mediated phosphorylation and ubiquitination of Discs large 1 (Dlg1), a known brake on myelination, which downregulates the phosphatidylinositol 3-kinase (PI3K)/v-AKT murine thymoma viral oncogene homolog (AKT) pathway. Interestingly, Kif13b also negatively regulates Dlg1 stability in oligodendrocytes, in which Dlg1, in contrast to Schwann cells, enhances AKT activation and promotes myelination. Thus, our data indicate that Kif13b is a negative regulator of CNS myelination. In summary, we propose a novel function for the Kif13b kinesin in glial cells as a key component of the PI3K/AKT signaling pathway, which controls myelination in both PNS and CNS. Kif13b is an unconventional kinesin that acts as a signaling molecule, regulating myelination via the Dlg1 scaffold in both Schwann cells (in the peripheral nervous system) and oligodendrocytes (in the central nervous system). Myelin is a multilayered extension of the Schwann and oligodendrocyte cell membranes, which wraps around neuronal axons to facilitate propagation of electric signals and to support axonal metabolism. However, the signals regulating myelin formation and how they are integrated and controlled to achieve homeostasis are still poorly understood. In Schwann cells, the Discs large 1 (Dlg1) protein is a known brake of myelination, which negatively regulates the amount of myelin produced so that myelin thickness is proportional to axonal diameter. In this paper, we report that in Schwann cells Dlg1 itself is tightly regulated to ensure proper myelination. We propose that Dlg1 function is further controlled by the Kif13b kinesin motor protein, which acts as a "brake of the brake" by downregulating Dlg1 activity. Surprisingly, we found that in oligodendrocytes Dlg1 is a positive and not a negative regulator of myelination. Thus, Kif13b-mediated negative regulation of Dlg1 ensures appropriate myelin production and thickness in the central nervous system. Our data further extend recently emerged unconventional roles for kinesins, which are usually implicated in cargo transport rather than in the modulation of signaling pathways. The elucidation of mechanisms regulating myelination may help to design specific approaches to favor re-myelination in demyelinating disorders in which this process is severely impaired.
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Affiliation(s)
- Roberta Noseda
- Division of Neuroscience, INSPE-Institute of Experimental Neurology, San Raffaele Scientific Institute, Milan, Italy
| | - Marta Guerrero-Valero
- Division of Neuroscience, INSPE-Institute of Experimental Neurology, San Raffaele Scientific Institute, Milan, Italy
| | - Valeria Alberizzi
- Division of Neuroscience, INSPE-Institute of Experimental Neurology, San Raffaele Scientific Institute, Milan, Italy
| | - Stefano C. Previtali
- Division of Neuroscience, INSPE-Institute of Experimental Neurology, San Raffaele Scientific Institute, Milan, Italy
- Department of Neurology, San Raffaele Scientific Institute, Milan, Italy
| | - Diane L. Sherman
- Centre for Neuroregeneration, University of Edinburgh, Edinburgh, United Kingdom
| | - Marilena Palmisano
- Hunter James Kelly Research Institute, Department of Biochemistry and Neurology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York, United States of America
| | - Richard L. Huganir
- The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Klaus-Armin Nave
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Goettingen, Germany
| | - Ana Cuenda
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
| | - Maria Laura Feltri
- Hunter James Kelly Research Institute, Department of Biochemistry and Neurology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York, United States of America
| | - Peter J. Brophy
- Centre for Neuroregeneration, University of Edinburgh, Edinburgh, United Kingdom
| | - Alessandra Bolino
- Division of Neuroscience, INSPE-Institute of Experimental Neurology, San Raffaele Scientific Institute, Milan, Italy
- * E-mail:
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25
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Walch L. Emerging role of the scaffolding protein Dlg1 in vesicle trafficking. Traffic 2014; 14:964-73. [PMID: 23829493 DOI: 10.1111/tra.12089] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 07/02/2013] [Accepted: 07/06/2013] [Indexed: 01/23/2023]
Abstract
Discs large 1 (Dlg1) is a modular scaffolding protein implicated in the control of cell polarity through assembly of specific multiprotein complexes, including receptors, ion channels and signaling proteins, at specialized zones of the plasma membrane. Recent data have shown that in addition to these well-known interaction partners, Dlg1 may also recruit components of the vesicle trafficking machinery either to the plasma membrane or to transport vesicles. Here, we discuss Dlg1 function in vesicle formation, targeting, tethering and fusion, in both the exocytotic and endocytotic pathways. These pathways contribute to cell functions as major and diverse as glutamatergic activity in the neurons, membrane homeostasis in Schwann cell myelination, insulin stimulation of glucose transport in adipocytes, or endothelial secretion of the hemostatic protein, von Willebrand factor (VWF).
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Affiliation(s)
- Laurence Walch
- INSERM U698, Université Paris 7, Hemostasis, Bio-engineering and Cardiovascular Remodeling, CHU X. Bichat, Paris, France.
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Fourie C, Li D, Montgomery JM. The anchoring protein SAP97 influences the trafficking and localisation of multiple membrane channels. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:589-94. [PMID: 23535319 DOI: 10.1016/j.bbamem.2013.03.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Revised: 02/26/2013] [Accepted: 03/15/2013] [Indexed: 12/23/2022]
Abstract
SAP97 is a member of the MAGUK family of proteins that play a major role in the trafficking and targeting of membrane ion channels and cytosolic structural proteins in multiple cell types. Within neurons, SAP97 is localised throughout the secretory trafficking pathway and at the postsynaptic density (PSD). SAP97 differs from other MAGUK family members largely in its long N-terminus and in the sequences between the SH3 and GUK domains, where SAP97 undergoes significant alternative splicing to produce multiple SAP97 isoforms. These splice insertions endow SAP97 with differential cellular localisation patterns and functional roles within neurons. With regard to membrane ion channels, SAP97 forms multi-protein complexes with AMPA and NMDA-type glutamate receptors, and Kv1.4, Kv4.2, and Kir2.2 potassium channels, playing a major role in trafficking and anchoring ion channel surface expression. This highlights SAP97 not only as a regulator of neuronal excitability, synaptic function and plasticity in the brain, but also as a target for the pathophysiology of a number of neurological disorders. This article is part of a Special Issue entitled: Reciprocal influences between cell cytoskeleton and membrane channels, receptors and transporters. Guest Editor: Jean Claude Hervé.
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Affiliation(s)
- Chantelle Fourie
- Department of Physiology, University of Auckland, New Zealand; Centre for Brain Research, University of Auckland, New Zealand
| | - Dong Li
- Department of Physiology, University of Auckland, New Zealand; Centre for Brain Research, University of Auckland, New Zealand
| | - Johanna M Montgomery
- Department of Physiology, University of Auckland, New Zealand; Centre for Brain Research, University of Auckland, New Zealand.
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Wu J, Ji X, Zhu L, Jiang Q, Wen Z, Xu S, Shao W, Cai J, Du Q, Zhu Y, Mao J. Up-regulation of microRNA-1290 impairs cytokinesis and affects the reprogramming of colon cancer cells. Cancer Lett 2012; 329:155-63. [PMID: 23142292 DOI: 10.1016/j.canlet.2012.10.038] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 10/25/2012] [Accepted: 10/27/2012] [Indexed: 02/07/2023]
Abstract
Abnormal cytokinesis increases the possibility of nuclear fusion in tumor cells. However, the role of microRNAs (miRNAs) in abnormal cytokinesis is unclear. Here, we found that miR-1290 was significantly up-regulated in clinical colon cancer tissues. Up-regulation of miR-1290 postponed cytokinesis and led to the formation of multinucleated cells. KIF13B was a target of miR-1290 that was involved in aberrant cytokinesis. Furthermore, enforced expression of miR-1290 activated the Wnt pathway and increased the reprogramming-related transcript factors c-Myc and Nanog. Our results suggest that up-regulation of miR-1290 in colon cancer cells impaired cytokinesis and affected reprogramming.
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Affiliation(s)
- Jia Wu
- Laboratory of Gastroenterology, Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, Zhejiang Province 310009, China
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Abstract
Kinesin molecular motors perform a myriad of intracellular transport functions. While their mechanochemical mechanisms are well understood and well-conserved throughout the superfamily, the cargo-binding and regulatory mechanisms governing the activity of kinesins are highly diverse and in general, are incompletely characterized. Here we present evidence from bioinformatic predictions indicating that most kinesin superfamily members contain significant regions of intrinsically disordered (ID) residues. ID regions can bind to multiple partners with high specificity, and are highly labile to post-translational modification and degradation signals. In kinesins, the predicted ID regions are primarily found in areas outside the motor domains, where primary sequences diverge by family, suggesting that ID may be a critical structural element for determining the functional specificity of individual kinesins. To support this idea, we present a systematic analysis of the kinesin superfamily, family by family, for predicted regions of ID. We combine this analysis with a comprehensive review of kinesin binding partners and post-translational modifications. We find two key trends across the entire kinesin superfamily. First, ID residues tend to be in the tail regions of kinesins, opposite the superfamily-conserved motor domains. Second, predicted ID regions correlate to regions that are known to bind to cargoes and/or undergo post-translational modifications. We therefore propose that ID is a structural element utilized by the kinesin superfamily in order to impart functional specificity to individual kinesins.
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Zhu J, Shang Y, Chen J, Zhang M. Structure and function of the guanylate kinase-like domain of the MAGUK family scaffold proteins. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s11515-012-1244-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Huckaba TM, Gennerich A, Wilhelm JE, Chishti AH, Vale RD. Kinesin-73 is a processive motor that localizes to Rab5-containing organelles. J Biol Chem 2011; 286:7457-67. [PMID: 21169635 PMCID: PMC3045001 DOI: 10.1074/jbc.m110.167023] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Revised: 12/14/2010] [Indexed: 01/21/2023] Open
Abstract
Drosophila Kinesin-73 (Khc-73), which plays a role in mitotic spindle polarity in neuroblasts, is a metazoan-specific member of the Kinesin-3 family of motors, which includes mammalian KIF1A and Caenorhabditis elegans Unc-104. The mechanism of Kinesin-3 motors has been controversial because some studies have reported that they transport cargo as monomers whereas other studies have suggested a dimer mechanism. Here, we have performed single-molecule motility and cell biological studies of Khc-73. We find that constructs containing the motor and the conserved short stretches of putative coiled-coil-forming regions are predominantly monomeric in vitro, but that dimerization allows for fast, processive movement and high force production (7 piconewtons). In Drosophila cell lines, we present evidence that Khc-73 can dimerize in vivo. We also show that Khc-73 is recruited specifically to Rab5-containing endosomes through its "tail" domain. Our results suggest that the N-terminal half of Khc-73 can undergo a monomer-dimer transition to produce a fast processive motor and that its C-terminal half possesses a specific Rab5-vesicle binding domain.
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Affiliation(s)
- Thomas M. Huckaba
- From the Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California 94158-2517
| | - Arne Gennerich
- the Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York 10461
| | - James E. Wilhelm
- the Section of Cell and Developmental Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, California 92093
| | - Athar H. Chishti
- the Department of Physiology, Tufts University School of Medicine, Boston, Massachusetts 02111, and
| | - Ronald D. Vale
- From the Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California 94158-2517
- the Howard Hughes Medical Institute, University of California, San Francisco, California 94158-2517
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31
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Tarbashevich K, Dzementsei A, Pieler T. A novel function for KIF13B in germ cell migration. Dev Biol 2011; 349:169-78. [DOI: 10.1016/j.ydbio.2010.10.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2010] [Revised: 09/19/2010] [Accepted: 10/14/2010] [Indexed: 10/18/2022]
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Hirokawa N, Niwa S, Tanaka Y. Molecular Motors in Neurons: Transport Mechanisms and Roles in Brain Function, Development, and Disease. Neuron 2010; 68:610-38. [DOI: 10.1016/j.neuron.2010.09.039] [Citation(s) in RCA: 668] [Impact Index Per Article: 47.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/22/2010] [Indexed: 12/11/2022]
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Par1b/MARK2 phosphorylates kinesin-like motor protein GAKIN/KIF13B to regulate axon formation. Mol Cell Biol 2010; 30:2206-19. [PMID: 20194617 DOI: 10.1128/mcb.01181-09] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Here we report that Par1b/MARK2 regulates axon formation via phosphorylation of a kinesin superfamily protein GAKIN/KIF13B. Accumulating evidence indicated the importance of the evolutionarily conserved kinase Par1b in the regulation of cell polarity. Using hippocampal neurons in culture, it has been shown that Par1b regulates axon specification, but the underlying mechanism remains uncharacterized. We identify GAKIN/KIF13B as a novel Par1b-binding protein and reveal that GAKIN/KIF13B is a physiological substrate for Par1b, and the phosphorylation sites are conserved from Drosophila. In hippocampal neurons, GAKIN/KIF13B accumulates at the distal part of the microtubules in the tips of axons, but not of dendrites. Overexpression of GAKIN/KIF13B by itself can induce the formation of extra axons, which is inhibited by the coexpression of Par1b in a manner dependent on its kinase activity. In contrast, small interfering RNA (siRNA)-mediated knockdown of GAKIN/KIF13B severely retards neurite extension and promotes the axonless phenotype. The extra axon phenotype caused by Par1b siRNA is suppressed by cointroduction of GAKIN/KIF13B siRNA, thus placing the GAKIN/KIF13B function downstream of Par1b. We also find that GAKIN/KIF13B acts downstream of the phosphatidylinositol 3-kinase (PI3K) signaling via Par1b phosphorylation. These results reveal that GAKIN/KIF13B is a key intermediate linking Par1b to the regulation of axon formation.
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Abstract
How membrane biosynthesis and homeostasis is achieved in myelinating glia is mostly unknown. We previously reported that loss of myotubularin-related protein 2 (MTMR2) provokes autosomal recessive demyelinating Charcot-Marie-Tooth type 4B1 neuropathy, characterized by excessive redundant myelin, also known as myelin outfoldings. We generated a Mtmr2-null mouse that models the human neuropathy. We also found that, in Schwann cells, Mtmr2 interacts with Discs large 1 (Dlg1), a scaffold involved in polarized trafficking and membrane addition, whose localization in Mtmr2-null nerves is altered. We here report that, in Schwann cells, Dlg1 also interacts with kinesin 13B (kif13B) and Sec8, which are involved in vesicle transport and membrane tethering in polarized cells, respectively. Taking advantage of the Mtmr2-null mouse as a model of impaired membrane formation, we provide here the first evidence for a machinery that titrates membrane formation during myelination. We established Schwann cell/DRG neuron cocultures from Mtmr2-null mice, in which myelin outfoldings were reproduced and almost completely rescued by Mtmr2 replacement. By exploiting this in vitro model, we propose a mechanism whereby kif13B kinesin transports Dlg1 to sites of membrane remodeling where it coordinates a homeostatic control of myelination. The interaction of Dlg1 with the Sec8 exocyst component promotes membrane addition, whereas with Mtmr2, negatively regulates membrane formation. Myelin outfoldings thus arise as a consequence of the loss of negative control on the amount of membrane, which is produced during myelination.
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35
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Capturing protein tails by CAP-Gly domains. Trends Biochem Sci 2008; 33:535-45. [PMID: 18835717 DOI: 10.1016/j.tibs.2008.08.006] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Revised: 08/29/2008] [Accepted: 08/29/2008] [Indexed: 12/29/2022]
Abstract
Cytoskeleton-associated protein-glycine-rich (CAP-Gly) domains are protein-interaction modules implicated in important cellular processes and in hereditary human diseases. A prominent function of CAP-Gly domains is to bind to C-terminal EEY/F-COO(-) sequence motifs present in alpha-tubulin and in some microtubule-associated protein tails; however, CAP-Gly domains also interact with other structural elements including end-binding homology domains, zinc-finger motifs and proline-rich sequences. Recent findings unravelled the link between tubulin tyrosination and CAP-Gly-protein recruitment to microtubules. They further provided a molecular basis for understanding the role of CAP-Gly domains in controlling dynamic cellular processes including the tracking and regulation of microtubule ends. It is becoming increasingly clear that CAP-Gly domains are also involved in coordinating complex and diverse aspects of cell architecture and signalling.
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36
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Functional involvement of human discs large tumor suppressor in cytokinesis. Exp Cell Res 2008; 314:3118-29. [PMID: 18760273 DOI: 10.1016/j.yexcr.2008.07.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2008] [Revised: 07/25/2008] [Accepted: 07/30/2008] [Indexed: 01/07/2023]
Abstract
Cytokinesis is the final step of cell division that completes the separation of two daughter cells. We found that the human discs large (hDlg) tumor suppressor homologue is functionally involved in cytokinesis. The guanylate kinase (GUK) domain of hDlg mediates the localization of hDlg to the midbody during cytokinesis, and over-expression of the GUK domain in U2OS and HeLa cells impaired cytokinesis. Mouse embryonic fibroblasts (MEFs) derived from dlg mutant mice contained an increased number of multinucleated cells and showed reduced proliferation in culture. A kinesin-like motor protein, GAKIN, which binds directly to the GUK domain of hDlg, exhibited a similar intracellular distribution pattern with hDlg throughout mitosis and localized to the midbody during cytokinesis. However, the targeting of hDlg and GAKIN to the midbody appeared to be independent of each other. The midbody localization of GAKIN required its functional kinesin-motor domain. Treatment of cells with the siRNA specific for hDlg and GAKIN caused formation of multinucleated cells and delayed cytokinesis. Together, these results suggest that hDlg and GAKIN play functional roles in the maintenance of midbody architecture during cytokinesis.
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37
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Yamada KH, Hanada T, Chishti AH. The effector domain of human Dlg tumor suppressor acts as a switch that relieves autoinhibition of kinesin-3 motor GAKIN/KIF13B. Biochemistry 2007; 46:10039-45. [PMID: 17696365 PMCID: PMC2525504 DOI: 10.1021/bi701169w] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The activity of motor proteins must be tightly regulated in the cells to prevent unnecessary energy consumption and to maintain proper distribution of cellular components. Loading of the cargo molecule is one likely mechanism to activate an inactive motor. Here, we report that the activity of the kinesin-3 motor protein, GAKIN, is regulated by the direct binding of its protein cargo, human discs large (hDlg) tumor suppressor. Recombinant GAKIN exhibits potent microtubule gliding activity but has little microtubule-stimulated ATPase activity in solution, suggesting that it exists in an autoinhibitory form. In vitro binding measurements revealed that defined segments of GAKIN, particularly the MAGUK binding stalk (MBS) domain and the motor domain, mediate intramolecular interactions to confer globular protein conformation. Direct binding of the SH3-I3-GUK module of hDlg to the MBS domain of GAKIN activates the microtubule-stimulated ATPase activity of GAKIN by approximately 10-fold. We propose that the cargo-mediated regulation of motor activity constitutes a general paradigm for the activation of kinesins.
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Affiliation(s)
| | | | - Athar H. Chishti
- * To whom correspondence should be addressed: A.H.C. (e-mail: , phone: 312-355-1293, Fax: 312-355-1297, mailing address: 909 S. Wolcott Ave. COMRB Room 5100, Chicago IL 60612, USA)
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38
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Abstract
Most cells are polarized. Embryonic and stem cells can use their polarity to generate cell diversity by asymmetric cell division, whereas differentiated cells use their polarity to execute specific functions. For example, fibroblasts form an actin-rich leading edge required for cell migration, neurons form distinctive axonal and dendritic compartments important for directional signaling, and epithelial cells have apical and basolateral cortical domains necessary for maintaining tissue impermeability. It is well established that actin and actin-associated proteins are essential for generating molecular and morphological cell polarity, but only recently has it become accepted that microtubules can induce and/or maintain polarity. One common feature among different cell types is that microtubules can establish the position of cortical polarity, but are not required for cortical polarity per se. In this review, we discuss how different cell types utilize microtubules and microtubule-associated signaling pathways to generate cortical cell polarity, highlight common mechanisms, and discuss open questions for directing future research.
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Affiliation(s)
- Sarah E Siegrist
- Institutes of Neuroscience and Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, Oregon 97403, USA
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39
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Kim E, Ko J. Molecular organization and assembly of the postsynaptic density of excitatory brain synapses. Results Probl Cell Differ 2006; 43:1-23. [PMID: 17068965 DOI: 10.1007/400_011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
The postsynaptic density (PSD) is a postsynaptic membrane specialization at excitatory synapses. The PSD is made of macromolecular multiprotein complexes, which contain a variety of synaptic proteins including membrane, scaffolding, and signaling proteins. By coaggregating with postsynaptic cell adhesion molecules, PSD proteins promote the formation and maturation of excitatory synapses. PSD proteins organize signaling pathways to coordinate structural and functional changes in synapses, and they regulate trafficking and recycling of glutamate receptors, which determines synaptic strength and plasticity. Synaptic activity dynamically regulates the assembly of the PSD through mechanisms including protein phosphorylation, palmitoylation, and protein degradation. PSD proteins associate with diverse motor proteins, suggesting that they function as adaptors linking motors to their specific cargoes.
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Affiliation(s)
- Eunjoon Kim
- National Creative Research Initiative Center for Synaptogenesis and Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon.
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40
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Horiguchi K, Hanada T, Fukui Y, Chishti AH. Transport of PIP3 by GAKIN, a kinesin-3 family protein, regulates neuronal cell polarity. ACTA ACUST UNITED AC 2006; 174:425-36. [PMID: 16864656 PMCID: PMC2064238 DOI: 10.1083/jcb.200604031] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Phosphatidylinositol-(3,4,5)-trisphosphate (PIP3), a product of phosphatidylinositol 3-kinase, is an important second messenger implicated in signal transduction and membrane transport. In hippocampal neurons, the accumulation of PIP3 at the tip of neurite initiates the axon specification and neuronal polarity formation. We show that guanylate kinase–associated kinesin (GAKIN), a kinesin-like motor protein, directly interacts with a PIP3-interacting protein, PIP3BP, and mediates the transport of PIP3-containing vesicles. Recombinant GAKIN and PIP3BP form a complex on synthetic liposomes containing PIP3 and support the motility of the liposomes along microtubules in vitro. In PC12 cells and cultured hippocampal neurons, transport activity of GAKIN contributes to the accumulation of PIP3 at the tip of neurites. In hippocampal neurons, altered accumulation of PIP3 by overexpression of GAKIN constructs led to the loss of the axonally differentiated neurites. Together, these results suggest that, in neurons, the GAKIN–PIP3BP complex transports PIP3 to the neurite ends and regulates neuronal polarity formation.
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Affiliation(s)
- Kaori Horiguchi
- Department of Pharmacology and Cancer Center, University of Illinois College of Medicine, Chicago, IL 60612, USA
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41
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Siegrist SE, Doe CQ. Microtubule-induced Pins/Galphai cortical polarity in Drosophila neuroblasts. Cell 2006; 123:1323-35. [PMID: 16377571 DOI: 10.1016/j.cell.2005.09.043] [Citation(s) in RCA: 213] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2005] [Revised: 08/26/2005] [Accepted: 09/22/2005] [Indexed: 12/23/2022]
Abstract
Cortical polarity regulates cell division, migration, and differentiation. Microtubules induce cortical polarity in yeast, but few examples are known in metazoans. We show that astral microtubules, kinesin Khc-73, and Discs large (Dlg) induce cortical polarization of Pins/Galphai in Drosophila neuroblasts; this cortical domain is functional for generating spindle asymmetry, daughter-cell-size asymmetry, and distinct sibling fates. Khc-73 localizes to astral microtubule plus ends, and Dlg/Khc-73 and Dlg/Pins coimmunoprecipitate, suggesting that microtubules induce Pins/Galphai cortical polarity through Dlg/Khc-73 interactions. The microtubule/Khc-73/Dlg pathway acts in parallel to the well-characterized Inscuteable/Par pathway, but each provides unique spatial and temporal information: The Inscuteable/Par pathway initiates at prophase to coordinate neuroblast cortical polarity with CNS tissue polarity, whereas the microtubule/Khc-73/Dlg pathway functions at metaphase to coordinate neuroblast cortical polarity with the mitotic spindle axis. These results identify a role for microtubules in polarizing the neuroblast cortex, a fundamental step for generating cell diversity through asymmetric cell division.
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Affiliation(s)
- Sarah E Siegrist
- Institutes of Neuroscience and Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, Oregon 97403, USA
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42
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Abstract
Cortical cell polarity controls mitotic spindle orientation in many cell types. In this issue of Cell, it is turned around and shown that the transfer of polarity information between the cortex and the spindle is not just one way. In Drosophila neuroblasts, the spindle also has polarizing activity on the cortex.
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Affiliation(s)
- Julie Ahringer
- The Gurdon Institute and Department of Genetics, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, United Kingdom.
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43
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Ataman B, Budnik V, Thomas U. Scaffolding proteins at the Drosophila neuromuscular junction. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2006; 75:181-216. [PMID: 17137929 DOI: 10.1016/s0074-7742(06)75009-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Bulent Ataman
- Department of Neurobiology, University of Massachusetts, Medical School, Worcester, Massachusetts 01605, USA
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44
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Centaurin-alpha1 and KIF13B kinesin motor protein interaction in ARF6 signalling. Biochem Soc Trans 2005; 33:1279-81. [PMID: 16246098 DOI: 10.1042/bst0331279] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The ARF (ADP-ribosylation factor) family of small GTPases regulate intracellular membrane trafficking by cycling between an inactive GDP- and an active GTP-bound form. Among the six known mammalian ARFs (ARF1-ARF6), ARF6 is the least conserved and plays critical roles in membrane trafficking and cytoskeletal dynamics near the cell surface. Since ARFs have undetectable levels of intrinsic GTP binding and hydrolysis, they are totally dependent on extrinsic GEFs (guanine nucleotide-exchange factors) for GTP binding and GAPs (GTPase-activating proteins) for GTP hydrolysis. We have recently isolated a novel KIF (kinesin) motor protein (KIF13B) that binds to centaurin-alpha1, an ARF6GAP that binds to the second messenger PIP3 [PtdIns(3,4,5)P3]. KIFs transport intracellular vesicles and recognize their cargo by binding to proteins (receptors) localized on the surface of the cargo vesicles. Identification of centaurin-alpha1 as a KIF13B interactor suggests that KIF13B may transport ARF6 and/or PIP3 using centaurin-alpha1 as its receptor. This paper reviews the studies carried out to assess the interaction and regulation of centaurin-alpha1 by KIF13B.
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45
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Venkateswarlu K, Hanada T, Chishti AH. Centaurin-α1 interacts directly with kinesin motor protein KIF13B. J Cell Sci 2005; 118:2471-84. [PMID: 15923660 DOI: 10.1242/jcs.02369] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Centaurin-α1 is a phosphatidylinositol 3,4,5-trisphosphate binding protein as well as a GTPase activating protein (GAP) for the ADP-ribosylation factor (ARF) family of small GTPases. To further understand its cellular function, we screened a rat brain cDNA library using centaurin-α1 as bait to identify centaurin-α1 interacting proteins. The yeast two-hybrid screen identified a novel kinesin motor protein as a centaurin-α1 binding partner. The motor protein, termed KIF13B, encoded by a single ∼9.5-kb transcript, is widely expressed with high levels observed in brain and kidney. Yeast two-hybrid and GST pull-down assays showed that the interaction between centaurin-α1 and KIF13B is direct and mediated by the GAP domain of centaurin-α1 and the stalk domain of KIF13B. Centaurin-α1 and KIF13B form a complex in vivo and the KIF13B interaction appears to be specific to centaurin-α1 as other members of the ARF GAP family did not show any binding activity. We also show that KIF13B and centaurin-α1 colocalize at the leading edges of the cell periphery whereas a deletion mutant of centaurin-α1 that lacks the KIF13B binding site, failed to colocalize with KIF13B in vivo. Finally, we demonstrate that KIF13B binding suppresses the ARF6 GAP activity of centaurin-α1 in intact cells. Together, our data suggest a mechanism where direct binding between centaurin-α1 and KIF13B could concentrate centaurin-α1 at the leading edges of cells, thus modulating ARF6 function.
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Affiliation(s)
- Kanamarlapudi Venkateswarlu
- Department of Pharmacology, School of Medical Sciences, The University of Bristol, University Walk, Bristol, BS8 1TD, UK.
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46
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Round JL, Tomassian T, Zhang M, Patel V, Schoenberger SP, Miceli MC. Dlgh1 coordinates actin polymerization, synaptic T cell receptor and lipid raft aggregation, and effector function in T cells. ACTA ACUST UNITED AC 2005; 201:419-30. [PMID: 15699074 PMCID: PMC2213022 DOI: 10.1084/jem.20041428] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Lipid raft membrane compartmentalization and membrane-associated guanylate kinase (MAGUK) family molecular scaffolds function in establishing cell polarity and organizing signal transducers within epithelial cell junctions and neuronal synapses. Here, we elucidate a role for the MAGUK protein, Dlgh1, in polarized T cell synapse assembly and T cell function. We find that Dlgh1 translocates to the immune synapse and lipid rafts in response to T cell receptor (TCR)/CD28 engagement and that LckSH3-mediated interactions with Dlgh1 control its membrane targeting. TCR/CD28 engagement induces the formation of endogenous Lck–Dlgh1–Zap70–Wiskott-Aldrich syndrome protein (WASp) complexes in which Dlgh1 acts to facilitate interactions of Lck with Zap70 and WASp. Using small interfering RNA and overexpression approaches, we show that Dlgh1 promotes antigen-induced actin polymerization, synaptic raft and TCR clustering, nuclear factor of activated T cell activity, and cytokine production. We propose that Dlgh1 coordinates TCR/CD28-induced actin-driven T cell synapse assembly, signal transduction, and effector function. These findings highlight common molecular strategies used to regulate cell polarity, synapse assembly, and transducer organization in diverse cellular systems.
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Affiliation(s)
- June L Round
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
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47
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Hirokawa N, Takemura R. Molecular motors and mechanisms of directional transport in neurons. Nat Rev Neurosci 2005; 6:201-14. [PMID: 15711600 DOI: 10.1038/nrn1624] [Citation(s) in RCA: 598] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Intracellular transport is fundamental for neuronal morphogenesis, function and survival. Many proteins are selectively transported to either axons or dendrites. In addition, some specific mRNAs are transported to dendrites for local translation. Proteins of the kinesin superfamily participate in selective transport by using adaptor or scaffolding proteins to recognize and bind cargoes. The molecular components of RNA-transporting granules have been identified, and it is becoming clear how cargoes are directed to axons and dendrites by kinesin superfamily proteins. Here we discuss the molecular mechanisms of directional axonal and dendritic transport with specific emphasis on the role of motor proteins and their mechanisms of cargo recognition.
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Affiliation(s)
- Nobutaka Hirokawa
- Department of Cell Biology and Anatomy, Graduate School of Medicine, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan.
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Taniuchi K, Nakagawa H, Nakamura T, Eguchi H, Ohigashi H, Ishikawa O, Katagiri T, Nakamura Y. Down-regulation of RAB6KIFL/KIF20A, a Kinesin Involved with Membrane Trafficking of Discs Large Homologue 5, Can Attenuate Growth of Pancreatic Cancer Cell. Cancer Res 2005. [DOI: 10.1158/0008-5472.105.65.1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
To identify novel molecular targets for treatment of pancreatic ductal adenocarcinoma (PDAC), we generated precise gene expression profiles of PDACs on a genome-wide cDNA microarray after populations of tumor cells were purified by laser microdissection. Through functional analysis of genes that were transactivated in PDACs, we identified RAB6KIFL as a candidate for development of drugs to treat PDACs at the molecular level. Knockdown of endogenous RAB6KIFL expression in PDAC cell lines by small interfering RNA drastically attenuated growth of those cells, suggesting an essential role for the gene product in maintaining viability of PDAC cells. RAB6KIFL belongs to the kinesin superfamily of motor proteins, which have critical functions in trafficking of molecules and organelles. Proteomics analyses using a polyclonal anti-RAB6KIFL antibody identified one of the cargoes transported by RAB6KIFL as discs, large homologue 5 (DLG5), a scaffolding protein that may link the vinexin-β-catenin complex at sites of cell-cell contact. Like RAB6KIFL, DLG5 was overexpressed in PDACs, and knockdown of endogenous DLG5 by small interfering RNA significantly suppressed the growth of PDAC cells as well. Decreased levels of endogenous RAB6KIFL in PDAC cells altered the subcellular localization of DLG5 from cytoplasmic membranes to cytoplasm. Our results imply that collaboration of RAB6KIFL and DLG5 is likely to be involved in pancreatic carcinogenesis. These molecules should be promising targets for development of new therapeutic strategies for PDACs.
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Affiliation(s)
- Keisuke Taniuchi
- 1Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan
- 3Department of Gastroenterology and Hepatology, Kochi Medical School, Nankoku, Japan
| | - Hidewaki Nakagawa
- 1Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Toru Nakamura
- 1Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Hidetoshi Eguchi
- 2Department of Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan; and
| | - Hiroaki Ohigashi
- 2Department of Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan; and
| | - Osamu Ishikawa
- 2Department of Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan; and
| | - Toyomasa Katagiri
- 1Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Yusuke Nakamura
- 1Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan
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Abstract
Molecular motors are a fascinating group of proteins that have vital roles in a huge variety of cellular processes. They all share the ability to produce force through the hydrolysis of adenosine triphosphate, and fall into classes groups: the kinesins, myosins and the dyneins. The kinesin superfamily itself can be split into three major groups depending on the position of the motor domain, which is localized N-terminally, C-terminally, or internally. This review focuses on the N-terminal kinesins, providing a brief overview of their roles within the cell, and illustrating recent key developments in our understanding of how these proteins function.
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Affiliation(s)
- Marcin J Wozniak
- University of Manchester, School of Biological Sciences, The Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
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Abstract
PDZ domains are protein-interaction domains that are often found in multi-domain scaffolding proteins. PDZ-containing scaffolds assemble specific proteins into large molecular complexes at defined locations in the cell. In the postsynaptic density of neuronal excitatory synapses, PDZ proteins such as PSD-95 organize glutamate receptors and their associated signalling proteins and determine the size and strength of synapses. PDZ scaffolds also function in the dynamic trafficking of synaptic proteins by assembling cargo complexes for transport by molecular motors. As key organizers that control synaptic protein composition and structure, PDZ scaffolds are themselves highly regulated by synthesis and degradation, subcellular distribution and post-translational modification.
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Affiliation(s)
- Eunjoon Kim
- National Creative Research Initiative Center for Synaptogenesis and Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Guseong-dong, Yuseong-gu, Daejeon 305-701, Korea.
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