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Liu N, Li M, Xie F, Lv J, Gao X, Zhang H, Gao J, Zheng A. Efficacy of mimetic viral dynein binding peptide binding nanoparticles in blood-brain barrier model. J Drug Deliv Sci Technol 2022. [DOI: 10.1016/j.jddst.2022.103523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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2
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Gupta M, Liu X, Teraoka SN, Wright JA, Gatti RA, Quinlan A, Concannon P. Genes affecting ionizing radiation survival identified through combined exome sequencing and functional screening. Hum Mutat 2021; 42:1124-1138. [PMID: 34153142 DOI: 10.1002/humu.24241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 05/04/2021] [Accepted: 06/13/2021] [Indexed: 11/09/2022]
Abstract
The study of genetic syndromes characterized by sensitivity to DNA damaging agents has provided important insights into the mechanisms that maintain genome stability and identified novel targets for cancer therapies. Here, we used exome sequencing to study 51 unrelated individuals with previously reported hypersensitivity to ionizing radiation as well as a range of neurologic, immunologic, and developmental features, but who did not clearly fit any previously defined genetic syndrome. Based on the combination of variant identification, computational evidence of deleteriousness, and functional screening, we identified three groups of subjects. Two subjects carried the bi-allelic loss of function variants in causative genes for known DNA damage response syndromes. Eight subjects carried the single loss of function variants in causative genes for DNA damage response syndromes, six of whom also carried predicted deleterious variants in other genes with DNA damage-related functions. Three subjects carried deleterious mutations in genes without obvious roles in DNA damage responses. However, treatment of U2OS cells with small interfering RNA targeting these genes resulted in significantly increased radiation sensitivity. Our results suggest that gene-gene interaction may contribute to ionizing radiation sensitivity as well as highlighting possible roles for several genes not obviously involved in the response to DNA damage.
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Affiliation(s)
- Meenal Gupta
- Department of Human Genetics and Department of Biomedical Informatics, University of Utah, Salt Lake City, Utah, USA
| | - Xiangfei Liu
- Genetics Institute and Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, Florida, USA
| | - Sharon N Teraoka
- Genetics Institute and Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, Florida, USA
| | - Jocyndra A Wright
- Genetics Institute and Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, Florida, USA
| | - Richard A Gatti
- UCLA Department of Pathology and Laboratory Medicine, and Department of Human Genetics, Los Angeles, California, USA
| | - Aaron Quinlan
- Department of Human Genetics and Department of Biomedical Informatics, University of Utah, Salt Lake City, Utah, USA
| | - Patrick Concannon
- Genetics Institute and Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, Florida, USA
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3
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Ahmad R, Kleineberg C, Nasirimarekani V, Su YJ, Goli Pozveh S, Bae A, Sundmacher K, Bodenschatz E, Guido I, Vidaković-koch T, Gholami A. Light-Powered Reactivation of Flagella and Contraction of Microtubule Networks: Toward Building an Artificial Cell. ACS Synth Biol 2021; 10:1490-1504. [PMID: 33761235 PMCID: PMC8218302 DOI: 10.1021/acssynbio.1c00071] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
![]()
Artificial systems
capable of self-sustained movement with self-sufficient
energy are of high interest with respect to the development of many
challenging applications, including medical treatments, but also technical
applications. The bottom-up assembly of such systems in the context
of synthetic biology is still a challenging task. In this work, we
demonstrate the biocompatibility and efficiency of an artificial light-driven
energy module and a motility functional unit by integrating light-switchable
photosynthetic vesicles with demembranated flagella. The flagellar
propulsion is coupled to the beating frequency, and dynamic ATP synthesis
in response to illumination allows us to control beating frequency
of flagella in a light-dependent manner. In addition, we verified
the functionality of light-powered synthetic vesicles in in
vitro motility assays by encapsulating microtubules assembled
with force-generating kinesin-1 motors and the energy module to investigate
the dynamics of a contractile filamentous network in cell-like compartments
by optical stimulation. Integration of this photosynthetic system
with various biological building blocks such as cytoskeletal filaments
and molecular motors may contribute to the bottom-up synthesis of
artificial cells that are able to undergo motor-driven morphological
deformations and exhibit directional motion in a light-controllable
fashion.
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Affiliation(s)
- Raheel Ahmad
- Max-Planck Institute for Dynamics and Self-Organization, Am Faßberg 17, 37077 Göttingen, Germany
| | - Christin Kleineberg
- Max-Planck Institute for Dynamics of Complex Technical Systems, Sandtorstraße 1, 39106 Magdeburg, Germany
| | - Vahid Nasirimarekani
- Microfluidics & BIOMICS Cluster UPV/EHU, University of the Basque Country UPV/EHU, 01006 Vitoria-Gasteiz, Spain
| | - Yu-Jung Su
- Max-Planck Institute for Dynamics and Self-Organization, Am Faßberg 17, 37077 Göttingen, Germany
| | - Samira Goli Pozveh
- Max-Planck Institute for Dynamics and Self-Organization, Am Faßberg 17, 37077 Göttingen, Germany
| | - Albert Bae
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States
| | - Kai Sundmacher
- Max-Planck Institute for Dynamics of Complex Technical Systems, Sandtorstraße 1, 39106 Magdeburg, Germany
- Otto von Guericke University, Universitaetsplatz 2, 39106 Magdeburg, Germany
| | - Eberhard Bodenschatz
- Max-Planck Institute for Dynamics and Self-Organization, Am Faßberg 17, 37077 Göttingen, Germany
- Institute for Dynamics of Complex Systems, Georg-August-University Göttingen, 37073 Göttingen, Germany
| | - Isabella Guido
- Max-Planck Institute for Dynamics and Self-Organization, Am Faßberg 17, 37077 Göttingen, Germany
| | - Tanja Vidaković-koch
- Max-Planck Institute for Dynamics of Complex Technical Systems, Sandtorstraße 1, 39106 Magdeburg, Germany
| | - Azam Gholami
- Max-Planck Institute for Dynamics and Self-Organization, Am Faßberg 17, 37077 Göttingen, Germany
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4
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Singh SK, Pandey H, Al-Bassam J, Gheber L. Bidirectional motility of kinesin-5 motor proteins: structural determinants, cumulative functions and physiological roles. Cell Mol Life Sci 2018; 75:1757-1771. [PMID: 29397398 PMCID: PMC11105280 DOI: 10.1007/s00018-018-2754-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 01/03/2018] [Accepted: 01/17/2018] [Indexed: 01/27/2023]
Abstract
Mitotic kinesin-5 bipolar motor proteins perform essential functions in mitotic spindle dynamics by crosslinking and sliding antiparallel microtubules (MTs) apart within the mitotic spindle. Two recent studies have indicated that single molecules of Cin8, the Saccharomyces cerevisiae kinesin-5 homolog, are minus end-directed when moving on single MTs, yet switch directionality under certain experimental conditions (Gerson-Gurwitz et al., EMBO J 30:4942-4954, 2011; Roostalu et al., Science 332:94-99, 2011). This finding was unexpected since the Cin8 catalytic motor domain is located at the N-terminus of the protein, and such kinesins have been previously thought to be exclusively plus end-directed. In addition, the essential intracellular functions of kinesin-5 motors in separating spindle poles during mitosis can only be accomplished by plus end-directed motility during antiparallel sliding of the spindle MTs. Thus, the mechanism and possible physiological role of the minus end-directed motility of kinesin-5 motors remain unclear. Experimental and theoretical studies from several laboratories in recent years have identified additional kinesin-5 motors that are bidirectional, revealed structural determinants that regulate directionality, examined the possible mechanisms involved and have proposed physiological roles for the minus end-directed motility of kinesin-5 motors. Here, we summarize our current understanding of the remarkable ability of certain kinesin-5 motors to switch directionality when moving along MTs.
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Affiliation(s)
- Sudhir Kumar Singh
- Department of Chemistry and Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, PO Box 653, 84105, Beer-Sheva, Israel
| | - Himanshu Pandey
- Department of Chemistry and Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, PO Box 653, 84105, Beer-Sheva, Israel
| | - Jawdat Al-Bassam
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, 95616, USA
| | - Larisa Gheber
- Department of Chemistry and Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, PO Box 653, 84105, Beer-Sheva, Israel.
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5
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Nixon B, Anderson AL, Smith ND, McLeod R, Johnston SD. The Australian saltwater crocodile (Crocodylus porosus) provides evidence that the capacitation of spermatozoa may extend beyond the mammalian lineage. Proc Biol Sci 2017; 283:rspb.2016.0495. [PMID: 27147099 DOI: 10.1098/rspb.2016.0495] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 04/11/2016] [Indexed: 01/08/2023] Open
Abstract
Although mammalian spermatozoa only acquire functional maturity as they are conveyed through the male (epididymal maturation) and female (capacitation) reproductive tracts, the degree of post-testicular development necessary to achieve fertilization in other vertebrate species remains far less clear. Indeed, despite reports that the epididymis of birds and reptiles is capable of secreting proteins that bind and modify the sperm surface characteristics, it remains unclear whether capacitation is a pre-requisite for fertilization in these species. Using the ancient reptilian Australian saltwater crocodile as a model, this study was undertaken to explore whether reptile sperm do undergo capacitation-like changes following ejaculation. Our studies revealed that crocodile spermatozoa experienced a rapid and sustained, cyclic-AMP mediated increase in progressive motility following incubation under conditions optimized for the induction of capacitation in mammalian species such as the mouse and human. This response was coupled with elevated levels of phosphorylation associated with both protein kinase A and tyrosine kinase substrates, the latter of which were predominantly localized within the sperm flagellum. In findings that also accord with mammalian spermatozoa, we confirmed a homologue of outer dense fibre 2 as one of the principal substrates for tyrosine phosphorylation. Overall, our findings support the concept that crocodile spermatozoa do undergo a process that is homologous to capacitation in preparation for fertilization of an ovum.
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Affiliation(s)
- Brett Nixon
- School of Environmental and Life Sciences, Discipline of Biological Sciences, The University of Newcastle, University Drive, Callaghan, New South Wales 2308, Australia
| | - Amanda L Anderson
- School of Environmental and Life Sciences, Discipline of Biological Sciences, The University of Newcastle, University Drive, Callaghan, New South Wales 2308, Australia
| | - Nathan D Smith
- Analytical and Biomolecular Research Facility, The University of Newcastle, University Drive, Callaghan, New South Wales 2308, Australia
| | - Robby McLeod
- Koorana Crocodile Farm, Coowonga, Queensland 4702, Australia
| | - Stephen D Johnston
- School of Agriculture and Food Science, The University of Queensland, Gatton, Queensland 4343, Australia
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6
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Mahale S, Kumar M, Sharma A, Babu A, Ranjan S, Sachidanandan C, Mylavarapu SVS. The Light Intermediate Chain 2 Subpopulation of Dynein Regulates Mitotic Spindle Orientation. Sci Rep 2016; 6:22. [PMID: 28003657 PMCID: PMC5431351 DOI: 10.1038/s41598-016-0030-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 11/03/2016] [Indexed: 12/11/2022] Open
Abstract
Cytoplasmic dynein 1 is a multi-protein intracellular motor essential for mediating several mitotic functions, including the establishment of proper spindle orientation. The functional relevance and mechanistic distinctions between two discrete dynein subpopulations distinguished only by Light Intermediate Chain (LIC) homologues, LIC1 and LIC2 is unknown during mitosis. Here, we identify LIC2-dynein as the major mediator of proper spindle orientation and uncover its underlying molecular mechanism. Cortically localized dynein, essential for maintaining correct spindle orientation, consists majorly of LIC2-dynein, which interacts with cortical 14-3-3 ε- ζ and Par3, conserved proteins required for orienting the spindle. LIC2-dynein is also responsible for the majority of dynein-mediated asymmetric poleward transport of NuMA, helping focus microtubule minus ends. In addition, LIC2-dynein dominates in equatorially aligning chromosomes at metaphase and in regulating mitotic spindle length. Key mitotic functions of LIC2 were remarkably conserved in and essential for early embryonic divisions and development in zebrafish. Thus LIC2-dynein exclusively engages with two major cortical pathways to govern spindle orientation. Overall, we identify a novel selectivity of molecular interactions between the two LICs in mitosis as the underlying basis for their uneven distribution of labour in ensuring proper spindle orientation.
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Affiliation(s)
- Sagar Mahale
- Laboratory of Cellular Dynamics, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, Haryana, 121001, India.,Affiliated to Manipal University, Manipal, Karnataka, 576104, India
| | - Megha Kumar
- Laboratory of Cellular Dynamics, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, Haryana, 121001, India
| | - Amit Sharma
- Laboratory of Cellular Dynamics, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, Haryana, 121001, India.,Affiliated to Manipal University, Manipal, Karnataka, 576104, India
| | - Aswini Babu
- CSIR-Institute of Genomics & Integrative Biology, South Campus, New Delhi, 110025, India.,Academy of Scientific and Innovative Research (AcSIR), New Delhi, 110025, India
| | - Shashi Ranjan
- CSIR-Institute of Genomics & Integrative Biology, South Campus, New Delhi, 110025, India
| | - Chetana Sachidanandan
- CSIR-Institute of Genomics & Integrative Biology, South Campus, New Delhi, 110025, India.,Academy of Scientific and Innovative Research (AcSIR), New Delhi, 110025, India
| | - Sivaram V S Mylavarapu
- Laboratory of Cellular Dynamics, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, Haryana, 121001, India. .,Affiliated to Manipal University, Manipal, Karnataka, 576104, India.
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7
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CRISPR/Cas9-Mediated Rapid Generation of Multiple Mouse Lines Identified Ccdc63 as Essential for Spermiogenesis. Int J Mol Sci 2015; 16:24732-50. [PMID: 26501274 PMCID: PMC4632774 DOI: 10.3390/ijms161024732] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 09/30/2015] [Accepted: 10/09/2015] [Indexed: 12/14/2022] Open
Abstract
Spermatozoa are flagellated cells whose role in fertilization is dependent on their ability to move towards an oocyte. The structure of the sperm flagella is highly conserved across species, and much of what is known about this structure is derived from studies utilizing animal models. One group of proteins essential for the movement of the flagella are the dyneins. Using the advanced technology of CRISPR/Cas9 we have targeted three dynein group members; Dnaic1, Wdr63 and Ccdc63 in mice. All three of these genes are expressed strongly in the testis. We generated mice with amino acid substitutions in Dnaic1 to analyze two specific phosphorylation events at S124 and S127, and generated simple knockouts of Wdr63 and Ccdc63. We found that the targeted phosphorylation sites in Dnaic1 were not essential for male fertility. Similarly, Wdr63 was not essential for male fertility; however, Ccdc63 removal resulted in sterile male mice due to shortened flagella. This study demonstrates the versatility of the CRISPR/Cas9 system to generate animal models of a highly complex system by introducing point mutations and simple knockouts in a fast and efficient manner.
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8
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Mencarelli C, Mercati D, Dallai R, Lupetti P. Ultrastructure of the sperm axoneme and molecular analysis of axonemal dynein in Ephemeroptera (Insecta). Cytoskeleton (Hoboken) 2014; 71:328-39. [PMID: 24668829 DOI: 10.1002/cm.21175] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 03/13/2014] [Accepted: 03/20/2014] [Indexed: 12/20/2022]
Abstract
The Ephemeroptera sperm axoneme is devoid of outer dynein arms (ODA) and exhibits a pronounced modification of the central pair complex (CPC), which is substituted by the central sheath (CS): a tubular element of unknown molecular composition. We performed a detailed ultrastructural analysis of sperm axonemes in the genera Cloeon and Ecdyonurus using quick-freeze, deep-etch electron microscopy, showing that the loss of the conventional CPC is not only concomitant with the loss of ODA, but also with a substantial modification in the longitudinal distribution of both radial spokes (RS) and inner dynein arms (IDA). Such structures are no longer distributed following the alternation of different repeats as in the 9 + 2 axoneme, but instead share a 32 nm longitudinal repeat: a multiple of the 8 nm repeat observed along the CS wall. Differently from the conventional CPC, the CS and the surrounding RS possess a ninefold symmetry, coherently with the three-dimensional pattern of motility observed in Cloeon free spermatozoa. Biochemical analyses revealed that ultrastructural modifications are concomitant with a reduced complexity of the IDA heavy chain complement. We propose that these structural and molecular modifications might be related to the relief from the evolutionary constraints imposed by the CPC on the basal 9 + 9 + 2 axoneme and could also represent the minimal set compatible with flagellar beating and progressive motility mechanically regulated as suggested by the geometric clutch hypothesis. © 2014 Wiley Periodicals, Inc.
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Affiliation(s)
- Caterina Mencarelli
- Department of Life Sciences, University of Siena, Via Aldo Moro 2, Siena, Italy
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9
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Affiliation(s)
- Regina M Turner
- Department of Clinical Studies, Center for Animal Transgenesis, Germ Cell Research, University of Pennsylvania School of Veterinary Medicine, Kennett Square, USA
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10
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Drosophila Dynein intermediate chain gene, Dic61B, is required for spermatogenesis. PLoS One 2011; 6:e27822. [PMID: 22145020 PMCID: PMC3228723 DOI: 10.1371/journal.pone.0027822] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2011] [Accepted: 10/26/2011] [Indexed: 11/19/2022] Open
Abstract
This study reports the identification and characterization of a novel gene, Dic61B, required for male fertility in Drosophila. Complementation mapping of a novel male sterile mutation, ms21, isolated in our lab revealed it to be allelic to CG7051 at 61B1 cytogenetic region, since two piggyBac insertion alleles, CG7051(c05439) and CG7051(f07138) failed to complement. CG7051 putatively encodes a Dynein intermediate chain. All three mutants, ms21, CG7051(c05439) and CG7051(f07138), exhibited absolute recessive male sterility with abnormally coiled sperm axonemes causing faulty sperm individualization as revealed by Phalloidin staining in Don Juan-GFP background. Sequencing of PCR amplicons uncovered two point mutations in ms21 allele and confirmed the piggyBac insertions in CG7051(c05439) and CG7051(f07138) alleles to be in 5'UTR and 4(th) exon of CG7051 respectively, excision of which reverted the male sterility. In situ hybridization to polytene chromosomes demonstrated CG7051 to be a single copy gene. RT-PCR of testis RNA revealed defective splicing of the CG7051 transcripts in mutants. Interestingly, expression of cytoplasmic dynein intermediate chain, α, β, γ tubulins and α-spectrin was normal in mutants while ultra structural studies revealed defects in the assembly of sperm axonemes. Bioinformatics further highlighted the homology of CG7051 to axonemal dynein intermediate chain of various organisms, including DNAI1 of humans, mutations in which lead to male sterility due to immotile sperms. Based on these observations we conclude that CG7051 encodes a novel axonemal dynein intermediate chain essential for male fertility in Drosophila and rename it as Dic61B. This is the first axonemal Dic gene of Drosophila to be characterized at molecular level and shown to be required for spermatogenesis.
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11
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Ma C, Gao Y, Chai G, Su H, Wang N, Yang Y, Li C, Miao D, Wu W. Djrho2 is involved in regeneration of visual nerves in Dugesia japonica. J Genet Genomics 2010; 37:713-23. [DOI: 10.1016/s1673-8527(09)60089-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2010] [Revised: 06/27/2010] [Accepted: 07/02/2010] [Indexed: 01/03/2023]
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12
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Yamashita S, Migita A, Hayashi K, Hirahara T, Kimura E, Maeda Y, Hirano T, Uchino M. Amyotrophic lateral sclerosis in a patient with Kartagener syndrome. ACTA ACUST UNITED AC 2010; 11:402-4. [PMID: 20550487 DOI: 10.3109/17482960903377071] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We present a case of a patient with clinically definite ALS, who had earlier suffered from Kartagener syndrome, which is characterized by the triad comprising chronic sinusitis, bronchiectasis, and situs inversus. Recent linkage and mutational analyses identified several genes that are responsible for Kartagener syndrome. Most of them encode subunits of axonemal dyneins, highlighting the importance of dynein motors to ciliary motility. Recent data indicate that defects in cytoplasmic dynein-mediated retrograde axonal transport are involved in the etiology of ALS. Genes encoding the dynein heavy chain of cytoplasmic and outer arm axonemal dyneins are reported to have similar sequences in their central and 3'-end regions. Although a causal link between ALS and Kartagener syndrome has not yet been definitely established, the precise relationship between disrupted axonemal dynein function in Kartagener syndrome and motor neuron death should be investigated.
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Affiliation(s)
- Satoshi Yamashita
- Department of Neurology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Honjo, Japan.
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13
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Tanaka M, Jin G, Yamazaki Y, Takahara T, Takuwa M, Nakamura T. Identification of candidate cooperative genes of the Apc mutation in transformation of the colon epithelial cell by retroviral insertional mutagenesis. Cancer Sci 2008; 99:979-85. [PMID: 18294281 PMCID: PMC11158175 DOI: 10.1111/j.1349-7006.2008.00757.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2007] [Revised: 01/06/2008] [Accepted: 01/07/2008] [Indexed: 12/18/2022] Open
Abstract
The mutation of Apc is an important early genetic event in colon carcinogenesis. However, it remains to be clarified what kinds of cooperative genes are required for complete carcinogenesis. To identify cooperative genes for the Apc(Min) mutation the authors carried out retroviral insertional mutagenesis (RIM) using Min mouse-derived IMCE colon epithelial cells. Anchorage-independent transformed colonies were induced by retroviral infection only in IMCE cells, while no transformation was found in young adult mouse colon (YAMC) cells that are normal for Apc. One hundred and fifty-seven retroviral integration sites (RIS) were identified in 101 independent transformants, and four common integration sites (CIS), Dnah3, Ahnak, Stk17b and Rbm9, were observed. Upregulation of Dnah3 and Ahnak, and truncation of Dnah3 due to the viral integration, was revealed. In addition, Dnah3-overexpressing IMCE cells showed impairment of microtubule function. These data suggest the importance of cytoskeletal function in Apc-related tumor development and the usefulness of RIM in non-hematopoietic tissues, providing new insight into the early stage of colon carcinogenesis.
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Affiliation(s)
- Miwa Tanaka
- Department of Carcinogenesis, The Cancer Institute, Japanese Foundation for Cancer Research, 3-10-6 Ariake, Koto-ku, Tokyo 135-8550, Japan
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14
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Quan L, Xiao R, Li W, Oh SA, Kong H, Ambrose JC, Malcos JL, Cyr R, Twell D, Ma H. Functional divergence of the duplicated AtKIN14a and AtKIN14b genes: critical roles in Arabidopsis meiosis and gametophyte development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2008; 53:1013-26. [PMID: 18088313 DOI: 10.1111/j.1365-313x.2007.03391.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Gene duplication is important for gene family evolution, allowing for functional divergence and innovation. In flowering plants, duplicated genes are widely observed, and functional redundancy of closely related duplicates has been reported, but few cases of functional divergence of close duplicates have been described. Here, we show that the Arabidopsis AtKIN14a and AtKIN14b genes encoding highly similar kinesins are two of the most closely related Arabidopsis paralogs, which were formed by a duplication event that occurred after the split of Arabidopsis and poplar. In addition, AtKIN14a and AtKIN14b exhibit varying degrees of coding sequence divergence. Further genetic studies of plants carrying atkin14a and/or atkin14b mutations indicate that, although these two genes have similar functions, there is clear evidence for functional divergence. Although both genes are important for male and female meiosis, AtKIN14a plays a more critical role in male meiosis than AtKIN14b. Moreover, either one of these two genes is necessary and sufficient for gametophyte development, indicating that they are redundant for this function. Therefore, AtKIN14a and AtKIN14b together play important roles in controlling plant reproductive development. Our results suggest that the AtKIN14a and AtKIN14b genes have retained similar functions in gametophyte development and female meiosis, but have evolved partially distinct functions in male meiosis, with AtKIN14a playing a more substantive role.
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Affiliation(s)
- Li Quan
- Department of Biology, the Pennsylvania State University, University Park, PA 16802, USA
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15
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Phillips GN, Fox BG, Markley JL, Volkman BF, Bae E, Bitto E, Bingman CA, Frederick RO, McCoy JG, Lytle BL, Pierce BS, Song J, Twigger SN. Structures of proteins of biomedical interest from the Center for Eukaryotic Structural Genomics. ACTA ACUST UNITED AC 2007; 8:73-84. [PMID: 17786587 DOI: 10.1007/s10969-007-9023-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2007] [Accepted: 07/17/2007] [Indexed: 12/01/2022]
Abstract
The Center for Eukaryotic Structural Genomics (CESG) produces and solves the structures of proteins from eukaryotes. We have developed and operate a pipeline to both solve structures and to test new methodologies. Both NMR and X-ray crystallography methods are used for structure solution. CESG chooses targets based on sequence dissimilarity to known structures, medical relevance, and nominations from members of the scientific community. Many times proteins qualify in more than one of these categories. Here we review some of the structures that have connections to human health and disease.
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Affiliation(s)
- George N Phillips
- Center for Eukaryotic Structural Genomics, Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA.
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16
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Morris RL, Hoffman MP, Obar RA, McCafferty SS, Gibbons IR, Leone AD, Cool J, Allgood EL, Musante AM, Judkins KM, Rossetti BJ, Rawson AP, Burgess DR. Analysis of cytoskeletal and motility proteins in the sea urchin genome assembly. Dev Biol 2006; 300:219-37. [PMID: 17027957 PMCID: PMC2590651 DOI: 10.1016/j.ydbio.2006.08.052] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2006] [Revised: 08/18/2006] [Accepted: 08/22/2006] [Indexed: 11/30/2022]
Abstract
The sea urchin embryo is a classical model system for studying the role of the cytoskeleton in such events as fertilization, mitosis, cleavage, cell migration and gastrulation. We have conducted an analysis of gene models derived from the Strongylocentrotus purpuratus genome assembly and have gathered strong evidence for the existence of multiple gene families encoding cytoskeletal proteins and their regulators in sea urchin. While many cytoskeletal genes have been cloned from sea urchin with sequences already existing in public databases, genome analysis reveals a significantly higher degree of diversity within certain gene families. Furthermore, genes are described corresponding to homologs of cytoskeletal proteins not previously documented in sea urchins. To illustrate the varying degree of sequence diversity that exists within cytoskeletal gene families, we conducted an analysis of genes encoding actins, specific actin-binding proteins, myosins, tubulins, kinesins, dyneins, specific microtubule-associated proteins, and intermediate filaments. We conducted ontological analysis of select genes to better understand the relatedness of urchin cytoskeletal genes to those of other deuterostomes. We analyzed developmental expression (EST) data to confirm the existence of select gene models and to understand their differential expression during various stages of early development.
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Affiliation(s)
- R L Morris
- Department of Biology, Wheaton College, Norton, MA 02766, USA.
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17
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Turner RM. Moving to the beat: a review of mammalian sperm motility regulation. Reprod Fertil Dev 2006; 18:25-38. [PMID: 16478600 DOI: 10.1071/rd05120] [Citation(s) in RCA: 188] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2005] [Accepted: 01/21/2005] [Indexed: 01/18/2023] Open
Abstract
Because it is generally accepted that a high percentage of poorly motile or immotile sperm will adversely affect male fertility, analysis of sperm motility is a central part of the evaluation of male fertility. In spite of its importance to fertility, poor sperm motility remains only a description of a pathology whose underlying cause is typically poorly understood. The present review is designed to bring the clinician up to date with the most current understanding of the mechanisms that regulate sperm motility and to raise questions about how aberrations in these mechanisms could be the underlying causes of this pathology.
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Affiliation(s)
- Regina M Turner
- Department of Clinical Studies, Center for Animal Transgenesis and Germ Cell Research, University of Pennsylvania School of Veterinary Medicine, New Bolton Center, Kennett Square, PA 19348, USA.
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18
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Song J, Tyler RC, Lee MS, Tyler EM, Markley JL. Solution structure of isoform 1 of Roadblock/LC7, a light chain in the dynein complex. J Mol Biol 2005; 354:1043-51. [PMID: 16289575 DOI: 10.1016/j.jmb.2005.10.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2005] [Accepted: 10/05/2005] [Indexed: 10/25/2022]
Abstract
Roadblock/LC7 is a member of a class of dynein light chains involved in regulating the function of the dynein complex. We have determined the three-dimensional structure of isoform 1 of the mouse Roadblock/LC7 cytoplasmic dynein light chain (robl1_mouse) by NMR spectroscopy. In contrast to a previously reported NMR structure of the human homolog with 96% sequence identity (PDB 1TGQ), which showed the protein as a monomer, our results indicate clearly that robl1 exists as a symmetric homodimer. The two beta3-strands pair with each other and form a continuous ten-stranded beta-sheet. The 25-residue alpha2-helix from one subunit packs antiparallel to that of the other subunit on the face of the beta-sheet. Zipper-like hydrophobic contacts between the two helices serve to stabilize the dimer. Through an NMR titration experiment, we localized the site on robl1_mouse that interacts with the 40 residue peptide spanning residues 243 through 282 of IC74-1_rat. These results provide physical evidence for a symmetrical interaction between dimeric robl1 and the two molecules of IC74-1 in the dynein complex.
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Affiliation(s)
- Jikui Song
- Center for Eukaryotic Structural Genomics, Department of Biochemistry, University of Wisconsin-Madison, WI 53706-1544, USA
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19
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Ahmed NT, Mitchell DR. ODA16p, a Chlamydomonas flagellar protein needed for dynein assembly. Mol Biol Cell 2005; 16:5004-12. [PMID: 16093345 PMCID: PMC1237099 DOI: 10.1091/mbc.e05-07-0627] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2005] [Revised: 08/02/2005] [Accepted: 08/03/2005] [Indexed: 11/11/2022] Open
Abstract
Dynein motors of cilia and flagella function in the context of the axoneme, a very large network of microtubules and associated proteins. To understand how dyneins assemble and attach to this network, we characterized two Chlamydomonas outer arm dynein assembly (oda) mutants at a new locus, ODA16. Both oda16 mutants display a reduced beat frequency and altered swimming behavior, similar to previously characterized oda mutants, but only a partial loss of axonemal dyneins as shown by both electron microscopy and immunoblots. Motility studies suggest that the remaining outer arm dyneins on oda16 axonemes are functional. The ODA16 locus encodes a 49-kDa WD-repeat domain protein. Homologues were found in mammalian and fly databases, but not in yeast or nematode databases, implying that this protein is only needed in organisms with motile cilia or flagella. The Chlamydomonas ODA16 protein shares 62% identity with its human homologue. Western blot analysis localizes more than 90% of ODA16p to the flagellar matrix. Because wild-type axonemes retain little ODA16p but can be reactivated to a normal beat in vitro, we hypothesize that ODA16p is not an essential dynein subunit, but a protein necessary for dynein transport into the flagellar compartment or assembly onto the axoneme.
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Affiliation(s)
- Noveera T Ahmed
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY 13210, USA
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20
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Nakamura T. NUP98 Fusion in Human Leukemia: Dysregulation of the Nuclear Pore and Homeodomain Proteins. Int J Hematol 2005; 82:21-7. [PMID: 16105755 DOI: 10.1532/ijh97.04160] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
NUP98 is fused to a variety of partner genes, including abdominal B-like HOX, in human myeloid and T-cell malignancies via chromosomal translocation involving 11p15. NUP98 encodes a 98-kd nucleoporin that is a component of the nuclear pore complex and functions in nucleocytoplasmic transport, with its N-terminal GLFG repeats used as a docking site for karyopherins. Disruption of NUP98 may affect the nuclear pore function, and the abnormal expression and altered function of fusion partners may also be critical for leukemia development. Recent studies using mouse models expressing NUP98-HOX have confirmed its leukemogenic potential, and cooperative genes for NUP98-HOXA9 in leukemogenesis have been identified in these studies.Thus, the NUP98 chimera is a unique molecule that provides valuable information regarding nuclear pore function and the role of the homeobox protein in leukemogenesis/carcinogenesis.
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Affiliation(s)
- Takuro Nakamura
- Department of Carcinogenesis, The Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan.
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21
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Abstract
Retroviral insertional mutagenesis has been applied to identify oncogenes that are important for both human and rodent carcinogenesis. The method reveals not only primary oncogenes but also cooperative genes that might be affected as second or third hits in multistep carcinogenesis. The use of genetically engineered mice such as NUP98-HOXA9 transgenic mice enabled efficient identification of cooperative genes, which provides important information for the molecular pathway in carcinogenesis/leukemogenesis. With use of the retrovirus mediated gene transfer system, retroviral insertional mutagenesis will provide invaluable information to understand genetic interaction in complex mechanisms of carcinogenesis.
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Affiliation(s)
- Takuro Nakamura
- Department of Carcinogenesis, The Cancer Institute, Japanese Foundation for Cancer Research, 1-37-1 Kami-Ikebukuro, Toshima-ku, Tokyo 170-8455.
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22
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Schmidt DJ, Rose DJ, Saxton WM, Strome S. Functional analysis of cytoplasmic dynein heavy chain in Caenorhabditis elegans with fast-acting temperature-sensitive mutations. Mol Biol Cell 2004; 16:1200-12. [PMID: 15616192 PMCID: PMC551485 DOI: 10.1091/mbc.e04-06-0523] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Cytoplasmic dynein, a minus-end-directed microtubule motor, has been implicated in many cellular and developmental processes. Identification of specific cellular processes that rely directly on dynein would be facilitated by a means to induce specific and rapid inhibition of its function. We have identified conditional variants of a Caenorhabditis elegans dynein heavy chain (DHC-1) that lose function within a minute of a modest temperature upshift. Mutant embryos generated at elevated temperature show defects in centrosome separation, pronuclear migration, rotation of the centrosome/nucleus complex, bipolar spindle assembly, anaphase chromosome segregation, and cytokinesis. Our analyses of mutant embryos generated at permissive temperature and then upshifted quickly just before events of interest indicate that DHC-1 is required specifically for rotation of the centrosome/nucleus complex, for chromosome congression to a well ordered metaphase plate, and for timely initiation of anaphase. Our results do not support the view that DHC-1 is required for anaphase B separation of spindle poles and chromosomes. A P-loop mutation identified in two independent dominant temperature-sensitive alleles of dhc-1, when engineered into the DHC1 gene of Saccharomyces cerevisiae, conferred a dominant temperature-sensitive dynein loss-of-function phenotype. This suggests that temperature-sensitive mutations can be created for time-resolved function analyses of dyneins and perhaps other P-loop proteins in a variety of model systems.
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Affiliation(s)
- Diane J Schmidt
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
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23
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Liu S, Hard R, Rankin S, Hennessey T, Pennock DG. Disruption of genes encoding predicted inner arm dynein heavy chains causes motility phenotypes in Tetrahymena. ACTA ACUST UNITED AC 2004; 59:201-14. [PMID: 15468164 DOI: 10.1002/cm.20034] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The multi-dynein hypothesis [Asai, 1995: Cell Motil Cytoskeleton 32:129-132] states: (1) there are many different dynein HC isoforms; (2) each isoform is encoded by a different gene; (3) different isoforms have different functions. Many studies provide evidence in support of the first two statements [Piperno et al., 1990: J Cell Biol 110:379-389; Kagami and Kamiya, 1992: J Cell Sci 103:653-664; Gibbons, 1995: Cell Motil Cytoskeleton 32:136-144; Porter et al., 1996: Genetics 144:569-585; Xu et al., 1999: J Eukaryot Microbiol 46:606-611] and there is evidence that outer arms and inner arms play different roles in flagellar beating [Brokaw and Kamiya, 1987: Cell Motil. Cytoskeleton 8:68-75]. However, there are few studies rigorously testing in vivo whether inner arm dyneins, especially the 1-headed inner arm dyneins, play unique roles. This study tested the third tenet of the multi-dynein hypothesis by introducing mutations into three inner arm dynein HC genes (DYH8, 9 and 12) that are thought to encode HCs associated with 1-headed inner arm dyneins. Southern blots, Northern blots, and RT-PCR analyses indicate that all three mutants (KO-8, 9, and 12) are complete knockouts. Each mutant swims slower than the wild-type cells. The beat frequency of KO-8 cells is lower than that of the wild-type cells while the beat frequencies of KO-9 and KO-12 are not different from that of wild-type cells. Our results suggest that each inner arm dynein HC is essential for normal cell motility and cannot be replaced functionally by other dynein HCs and that not all of the 1-headed inner arm dyneins play the same role in ciliary motility. Thus, the results of our study support the multi-dynein hypothesis [Asai, 1995: Cell Motil Cytoskeleton 32:129-132].
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Affiliation(s)
- Siming Liu
- Department of Zoology, Miami University, Oxford, OH 45056, USA
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24
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McManus IC, Mitchison HM, Chung EMK, Stubbings GF, Martin N. Primary ciliary dyskinesia (Siewert's/Kartagener's syndrome): respiratory symptoms and psycho-social impact. BMC Pulm Med 2003; 3:4. [PMID: 14641928 PMCID: PMC317322 DOI: 10.1186/1471-2466-3-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2003] [Accepted: 11/27/2003] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Although the pathophysiological defect in primary ciliary dyskinesia (PCD; Siewert's/Kartagener's syndrome) is now well characterised, there are few studies of the impact of the condition upon health function, particularly in later life. This study assesses the health impact of the condition in a large group of patients. In addition, it assesses the similarity in age of diagnosis, symptoms and problems of those with situs inversus (PCD-SI) and those with situs solitus (PCD-SS). METHODS Postal questionnaire sent to members of the UK Primary Ciliary Dyskinesia Family Support Group. The questionnaire contained the St. George's Respiratory Questionnaire (SGRQ) and the SF-36 questionnaire for assessing health status. RESULTS 93 questionnaires were returned, representing a 66% response rate. Replies were received from similar numbers of PCD-SI and PCD-SS. Individuals with PCD-SI did not show a significant tendency to be diagnosed earlier, and neither did they show any difference in their symptoms, or the relationship of symptoms to age. Respiratory symptoms were fairly constant up until the age of about 25, after which there was a slow increase in symptoms, and a decline in health status, patients over the age of 40 being about one and a half standard deviations below the mean on the physical component score of the PCS. Patients diagnosed earlier in life, and hence who had received more treatment for their condition, had better scores on the SGRQ Impact and Activity scores. CONCLUSIONS PCD is a chronic condition which has a progressively greater impact on health in the second half of life, producing significant morbidity and restriction of life style. Early diagnosis, and hence earlier treatment, may improve symptoms and the impact of the condition.
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Affiliation(s)
- I Christopher McManus
- Department of Psychology, University College London, Gower Street, London WC1E 6BT, UK
| | - Hannah M Mitchison
- Department of Paediatrics and Child Health, University College London, Gower Street, London WC1E 6BT, UK
| | - Eddie MK Chung
- Department of Paediatrics and Child Health, University College London, Gower Street, London WC1E 6BT, UK
| | - Georgina F Stubbings
- Department of Psychology, University College London, Gower Street, London WC1E 6BT, UK
| | - Naomi Martin
- Department of Psychology, University College London, Gower Street, London WC1E 6BT, UK
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25
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Hirokawa N, Takemura R. Biochemical and molecular characterization of diseases linked to motor proteins. Trends Biochem Sci 2003; 28:558-65. [PMID: 14559185 DOI: 10.1016/j.tibs.2003.08.006] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent studies have revealed that kinesin, dynein and myosin each form large superfamilies and participate in many different intracellular transport systems. Importantly, these motor proteins play significant roles in the pathogenesis of a variety of diseases. Studies using knockout mice for kinesin KIF1B have led to the identification of the cause of a human hereditary neuropathy, Charcot-Marie-Tooth disease type 2A. The function of members of the dynein superfamily whose existence has previously only been confirmed through genome databases, has been revealed by studies of immotile cilia syndrome. Unconventional myosins have been shown to function in the inner-ear cells by examination of hereditary human hearing impairment and studies using mouse models. In addition, some diseases are caused by mutations, not in the motor itself, but in the proteins associated with the motor proteins. Here, we discuss the relationship of these motor proteins and how they contribute to disease in molecular terms.
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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, 113-0033, Tokyo, Japan.
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26
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Magee TR, Ferrini MG, Davila HH, Zeller CB, Vernet D, Sun J, Lalani R, Burnett AL, Rajfer J, González-Cadavid NF. Protein inhibitor of nitric oxide synthase (NOS) and the N-methyl-D-aspartate receptor are expressed in the rat and mouse penile nerves and colocalize with penile neuronal NOS. Biol Reprod 2003; 68:478-88. [PMID: 12533411 DOI: 10.1095/biolreprod.102.007310] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Nitrergic neurotransmission triggering penile erection is mediated by nitric oxide (NO) synthesized in the cavernosal nerves of the penis by penile neuronal NO synthase (PnNOS). In the central nervous system, nNOS is activated by the N-methyl-D-aspartate receptor (NMDAR) and, presumably, is inhibited by the protein inhibitor of NOS (PIN). The PnNOS and NMDAR are expressed in the penis, and PnNOS has been localized in penile nerves. Both proteins colocalize with PIN in the hypothalamus and the spinal cord involved in the control of erection. The present study aimed to elucidate the relationship between PnNOS, PIN, and NMDAR in the penis. It was found that in the rat, PIN was expressed in the pelvic ganglion and the cavernosal nerve, and penile PIN cDNA was cloned, sequenced, and expressed. Immunohistochemistry localized PIN to the cavernosal and dorsal nerve of the penis, whereas NMDAR was not detected in the latter. Dual-fluorescence labeling showed that PnNOS colocalized with PIN in both nerves but with NMDAR only in the cavernosal nerve. Aging did not affect the mRNA levels of PnNOS, nNOS, NMDAR, and PIN. Both PIN and NMDAR were detected in penile nerves of the wild-type and nNOS(-/-) mouse. The PIN protein did not inhibit or bind NOS in penile extracts, and in vivo, PIN cDNA reduced the erectile response to electrical field stimulation. In conclusion, PIN and NMDAR colocalize with PnNOS in penile nerves, but the functional significance of these protein interactions for penile erection remains to be elucidated.
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Affiliation(s)
- T R Magee
- Department of Urology, UCLA School of Medicine, Los Angeles, California 90095, USA
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27
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Chen C, Marcus A, Li W, Hu Y, Calzada JPV, Grossniklaus U, Cyr RJ, Ma H. The Arabidopsis ATK1 gene is required for spindle morphogenesis in male meiosis. Development 2002; 129:2401-9. [PMID: 11973272 DOI: 10.1242/dev.129.10.2401] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The spindle plays a central role in chromosome segregation during mitosis and meiosis. In particular, various kinesins are thought to play crucial roles in spindle structure and function in both mitosis and meiosis of fungi and animals. A group of putative kinesins has been previously identified in Arabidopsis, called ATK1-ATK4 (previously known as KATA-KATD), but their in vivo functions have not been tested with genetic studies. We report here the isolation and characterization of a mutant, atk1-1, which has a defective ATK1 gene. The atk1-1 mutant was identified in a collection of Ds transposon insertion lines by its reduced fertility. Reciprocal crosses between the atk1-1 mutant and wild type showed that only male fertility was reduced, not female fertility. Molecular analyses, including revertant studies, indicated that the Ds insertion in the ATK1 gene was responsible for the fertility defect. Light microscopy revealed that, in the atk1-1 mutant, male meiosis was defective, producing an abnormal number of microspores of variable sizes. Further cytological studies indicated that meiotic chromosome segregation and spindle organization were both abnormal in the mutant. Specifically, the atk1-1 mutant male meiotic cells had spindles that were broad, unfocused and multi-axial at the poles at metaphase I, unlike the typical fusiform bipolar spindle found in the wild-type metaphase I cells. Therefore, the ATK1 gene plays a crucial role in spindle morphogenesis in male Arabidopsis meiosis.
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Affiliation(s)
- Changbin Chen
- Department of Biology, The Pennsylvania State University, University Park, PA 16802 USA
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28
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Jiang J, Yu L, Huang X, Chen X, Li D, Zhang Y, Tang L, Zhao S. Identification of two novel human dynein light chain genes, DNLC2A and DNLC2B, and their expression changes in hepatocellular carcinoma tissues from 68 Chinese patients. Gene 2001; 281:103-13. [PMID: 11750132 DOI: 10.1016/s0378-1119(01)00787-9] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Two full-length cDNAs, DNLC2A and DNLC2B, were cloned and characterized. Their open reading frames respectively encode 96 amino acids which are most closely homologous to roadblock/LC7, one member of an ancient dynein light chain protein family, conserved in nematode, fruit fly, mouse and rat. The DNLC2A was expressed in 12 of 16 human tissues examined, with especially strong expression in heart, liver and brain, whereas there was weak expression in lung, prostate, testis, small intestine and colon. The expression of DNLC2B was generally high compared with that of DNLC2A except in liver. Northern blotting and/or semi-quantitative RT-PCR analysis examined the expression changes of DNLC2A and DNLC2B in 68 hepatocellular carcinoma tissue samples. It was revealed that DNLC2A was up-regulated (45 out of the 68 cases) while DNLC2B was down-regulated (44 out of 68 cases), compared with their adjacent tumor-free liver tissues. Interestingly, among the total 68 liver cancer samples tested, DNLC2A was up-regulated while DNLC2B was down-regulated in 28 cases; DNLC2A was up-regulated while no obvious change was observed for DNLC2B in 10 cases; no obvious change was observed for DNLC2A while DNLC2B was down-regulated in 14 cases. Although the underlying mechanism is not clear to date, the apparent up-regulation of DNLC2A and down-regulation of DNLC2B suggest that these genes might be involved in tumor progression. On the other hand, the different expression changes of the two homologous genes indicate that hepatocellular carcinomas are caused by different pathological mechanisms. In addition, DNLC2A was assigned to human chromosome 20q12-q13.11 near the marker D20S106 by radiation hybrid mapping.
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MESH Headings
- Adult
- Aged
- Amino Acid Sequence
- Base Sequence
- Blotting, Northern
- Carcinoma, Hepatocellular/enzymology
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/pathology
- China
- Chromosome Mapping
- Chromosomes, Human, Pair 20/genetics
- Cloning, Molecular
- Cytoplasmic Dyneins
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- Dyneins/genetics
- Female
- Gene Expression Regulation, Enzymologic
- Humans
- Isoenzymes/genetics
- Liver Neoplasms/enzymology
- Liver Neoplasms/genetics
- Liver Neoplasms/pathology
- Male
- Middle Aged
- Molecular Sequence Data
- Neoplasm Proteins
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Tissue Distribution
- Tumor Cells, Cultured
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Affiliation(s)
- J Jiang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, 220 Handan Road, Shanghai 200433, PR China
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29
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Sadek CM, Damdimopoulos AE, Pelto-Huikko M, Gustafsson JA, Spyrou G, Miranda-Vizuete A. Sptrx-2, a fusion protein composed of one thioredoxin and three tandemly repeated NDP-kinase domains is expressed in human testis germ cells. Genes Cells 2001; 6:1077-90. [PMID: 11737268 DOI: 10.1046/j.1365-2443.2001.00484.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Thioredoxins (Trx) are small redox proteins that function as general protein disulphide reductases and regulate several cellular processes such as transcription factor DNA binding activity, apoptosis and DNA synthesis. In mammalian organisms, thioredoxins are generally ubiquitously expressed in all tissues, with the exception of Sptrx-1 which is specifically expressed in sperm cells. RESULTS We report here the identification and characterization of a novel member of the thioredoxin family, the second with a tissue-specific distribution in human sperm, termed Sptrx-2. The Sptrx-2 ORF (open reading frame) encodes for a protein of 588 amino acids with two different domains: an N-terminal thioredoxin domain encompassing the first 105 residues and a C-terminal domain composed of three repeats of a NDP kinase domain. The Sptrx-2 gene spans about 51 kb organized in 17 exons and maps at locus 7p13-14. Sptrx-2 mRNA is exclusively expressed in human testis, mainly in primary spermatocytes, while Sptrx-2 protein expression is detected from the pachytene spermatocytes stage onwards, peaking at round spermatids stage. Recombinant full-length Sptrx-2 expressed in bacteria displayed neither thioredoxin nor NDP kinase enzymatic activity. CONCLUSIONS The sperm specific expression of Sptrx-2, together with its chromosomal assignment to a position reported as a potential locus for flagellar anomalies and male infertility phenotypes such as primary ciliary dyskinesia, suggests that it might be a novel component of the human sperm axonemal organization.
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Affiliation(s)
- C M Sadek
- Center for Biotechnology, Department of Biosciences at NOVUM, Karolinska Institutet, S-14157 Huddinge, Sweden
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30
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Mencarelli C, Lupetti P, Rosetto M, Mercati D, Heuser JE, Dallai R. Molecular structure of dynein and motility of a giant sperm axoneme provided with only the outer dynein arm. CELL MOTILITY AND THE CYTOSKELETON 2001; 50:129-46. [PMID: 11807935 DOI: 10.1002/cm.10004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The peculiar sperm axoneme of the dipteran Asphondylia ruebsaameni is characterized by an extraordinarily high number of microtubule doublets (up to 2,500) arranged in double parallel spirals. Doublets of the inner row of each spiral are tilted, so that their outer arms point towards the B-tubule of the next doublet in the outer row. Doublets are provided with only the outer arm, and no structure related to the central pair/radial spoke complex is present. When analyzed by quick-freeze, deep-etch electron microscopy, the structure of the dynein arms was shown to share the same organization described in other organisms; however, it appears to be somewhat more complex than that previously found in a related dipteran species, Monarthropalpus flavus, since the foot region of the arms displays a globular extra-domain that is intercalated between adjacent arms. Treatment of demembranated sperm with ATP and vanadate induced conformational changes in the dynein arms. SDS-page suggested the presence of a single dynein high molecular weight band or, in the gels with the best electrophoretic resolution, of two very closely spaced bands. This polypeptide positively reacted with a polyclonal antibody raised against a specific amino acid sequence located in the phosphate-binding loop of the dynein catalytic site. Dynein heavy chain-related DNA sequences corresponding to the catalytic phosphate-binding region were amplified by RT-PCR. Two distinct fragments (Asph-ax1 and Asph-ax2) encoding axonemal dynein sequences were identified. Southern blot analysis performed on genomic DNA using these sequences as a probe showed that they are part of different genes. An intron was identified in the Asph-ax1 fragment at a position corresponding to the site of a nucleotide deletion in the putative pseudogene of Monarthropalpus. Asphondylia spermatozoa exhibited in vivo a whirling movement both in the deferent duct and in the spermatheca, but they were unable to undergo processive movement in vitro. They propagated a three-dimensional wave only when constrained in a bent configuration by some mechanical means. The phylogenetic relationships between the two dipteran species, Monarthopalpus and Asphondylia, based on these biochemical and molecular data are also discussed.
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Affiliation(s)
- C Mencarelli
- Dipartimento di Biologia Evolutiva, Università di Siena, Siena, Italy
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Reilein AR, Rogers SL, Tuma MC, Gelfand VI. Regulation of molecular motor proteins. INTERNATIONAL REVIEW OF CYTOLOGY 2001; 204:179-238. [PMID: 11243595 DOI: 10.1016/s0074-7696(01)04005-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Motor proteins in the kinesin, dynein, and myosin superfamilies are tightly regulated to perform multiple functions in the cell requiring force generation. Although motor proteins within families are diverse in sequence and structure, there are general mechanisms by which they are regulated. We first discuss the regulation of the subset of kinesin family members for which such information exists, and then address general mechanisms of kinesin family regulation. We review what is known about the regulation of axonemal and cytoplasmic dyneins. Recent work on cytoplasmic dynein has revealed the existence of multiple isoforms for each dynein chain, making the study of dynein regulation more complicated than previously realized. Finally, we discuss the regulation of myosins known to be involved in membrane trafficking. Myosins and kinesins may be evolutionarily related, and there are common themes of regulation between these two classes of motors.
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Affiliation(s)
- A R Reilein
- Department of Cell and Structural Biology, University of Illinois, Urbana-Champaign, Urbana 61801, USA
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Kim SW, Ihn KS, Han SH, Seong SY, Kim IS, Choi MS. Microtubule- and dynein-mediated movement of Orientia tsutsugamushi to the microtubule organizing center. Infect Immun 2001; 69:494-500. [PMID: 11119542 PMCID: PMC97908 DOI: 10.1128/iai.69.1.494-500.2001] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The host cell microfilaments and microtubules (MTs) are known to play a critical role in the life cycles of several pathogenic intracellular microbes by providing for successful invasion and promoting movement of the pathogen once inside the host cell cytoplasm. Orientia tsutsugamushi, an obligate intracellular bacterium, enters host cells by induced phagocytosis, escapes to the cytosol, and then replicates in the cytosol. ECV304 cells infected with O. tsutsugamushi revealed the colocalization of the MT organizing center (MTOC) and cytosolic orientiae by indirect immunofluorescence assay. Using immunofluorescence microscopy in the presence and absence of MT-depolymerizing agents (colchicine and nocodazole), it was shown that the cytosolic oriential movement was mediated by MTs. By transfection study (overexpression of dynamitin [also called p50], which is known to associate with dynein-dependent movement), the movement of O. tsutsugamushi to the MTOC was also mediated by dynein, the minus-end-directed MT-related motor. Although the significance of this movement in the life cycle of O. tsutsugamushi was not proven, we propose that the cytosolic O. tsutsugamushi bacteria use MTs and dyneins to propel themselves from the cell periphery to the MTOC.
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Affiliation(s)
- S W Kim
- Department of Microbiology and Immunology, Seoul National University College of Medicine, and Institute of Endemic Disease, Seoul National University Medical Research Center, 28 Yongon-dong, Chongno-gu, Seoul 110-799, Republic of Korea
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33
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Dini M, Lo Russo G, Baroni G, Colafranceschi M. Cutaneous ciliated cyst: a case report with immunohistochemical evidence for dynein in ciliated cells. Am J Dermatopathol 2000; 22:519-23. [PMID: 11190444 DOI: 10.1097/00000372-200012000-00007] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cutaneous ciliated cysts (CCCs) are rare benign lesions predominantly occurring in the lower limbs of young women. We observed such a lesion in the perineal region of a 12-year-old girl. The histogenetic interpretation of CCCs is controversial. The similarity of the epithelial lining of the cyst to the salpingeal epithelium supports the hypothesis of a Müllerian heterotopia. Strong dynein positivity observed immunohistochemically in the apical portion of CCC lining cells suggests the integrity of the ciliary apparatus. There was a marked similarity between a CCC and normal salpingeal epithelium in the mode of staining for dynein, whereas the dynein reactivity of bronchial epithelial cells showed larger cytoplasmic aggregates of positive material in proximity to the nucleus. No immunohistochemical staining for estrogen or progesterone receptors was identified in our observation, although this finding could have supported the Müllerian histogenetic hypothesis. To the best of our knowledge, this is the first time that antidynein immunohistochemistry has been applied to paraffin-embedded samples from human surgical pathology.
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Affiliation(s)
- M Dini
- Department of Plastic Surgery, University of Florence, Italy
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34
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Koonin EV, Aravind L. Dynein light chains of the Roadblock/LC7 group belong to an ancient protein superfamily implicated in NTPase regulation. Curr Biol 2000; 10:R774-6. [PMID: 11084347 DOI: 10.1016/s0960-9822(00)00774-0] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- E V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland 20894, USA
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35
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Light-induced Down-regulation of the Rat Class 1 Dynein-associated Protein robl/LC7-like Gene in Visual Cortex. J Biol Chem 2000. [DOI: 10.1016/s0021-9258(19)61494-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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36
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Andersson M, Peltoniemi O, Makinen A, Sukura A, Rodriguez-Martinez H. The Hereditary 'Short Tail' Sperm Defect - A New Reproductive Problem in Yorkshire Boars. Reprod Domest Anim 2000. [DOI: 10.1046/j.1439-0531.2000.00196.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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37
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Byers HR, Yaar M, Eller MS, Jalbert NL, Gilchrest BA. Role of cytoplasmic dynein in melanosome transport in human melanocytes. J Invest Dermatol 2000; 114:990-7. [PMID: 10771482 DOI: 10.1046/j.1523-1747.2000.00957.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cytoplasmic dynein is a microtubule-associated retrograde-directed motor molecule for transport of membrane-bound organelles. To determine whether cytoplasmic dynein is expressed in melanocytes, we performed reverse transcriptase polymerase chain reaction using melanocyte cDNA and primers complementary to human brain cytoplasmic dynein heavy chain. A polymerase chain reaction product of the expected molecular size was generated and the identity was confirmed by sequence analysis. Western blotting of total melanocyte proteins reacted with an anti-intermediate chain cytoplasmic dynein antibody identified the appropriate 74 kDa band. To determine whether cytoplasmic dynein plays a role in melanosome transport, duplicate cultures were treated with cytoplasmic dynein antisense or sense (control) oligodeoxynucleotides and the cells were observed by high-resolution time-lapse microscopy, which allows visualization of melanosomal aggregates and individual melanosomes. Antisense-treated melanocytes demonstrated a strong anterograde transport of melanosomes from the cell body into the dendrites, whereas melanosome distribution was not affected in sense-treated melanocytes. To determine whether ultraviolet irradiation modifies cytoplasmic dynein expression, melanocyte cultures were exposed to increasing doses of solar-simulated irradiation, equivalent to a mild to moderate sunburn exposure for intact skin. Within 24 h, doses of 5 and 10 mJ per cm2 induced cytoplasmic dynein protein, whereas doses of 30 mJ per cm2 or more were associated with decreased levels of cytoplasmic dynein compared with sham-irradiated controls. Our data show that cytoplasmic dynein participates in retrograde melanosomal transport in human melanocytes and suggest that the altered melanosomal distribution in skin after sun exposure is due, at least in part, to decreased cytoplasmic dynein levels resulting in augmented anterograde transport.
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Affiliation(s)
- H R Byers
- Department of Dermatology, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
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Abstract
Research over the past 18 months has revealed that many membranous organelles move along both actin filaments and microtubules. It is highly likely that the activity of the microtubule motors, myosins and static linker proteins present on any organelle are co-ordinately regulated and that this control is linked to the processes of membrane traffic itself.
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Affiliation(s)
- V J Allan
- School of Biological Sciences, University of Manchester, 2.205 Stopford Building, Oxford Road, Manchester, M13 9PT, UK.
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39
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Bowman AB, Patel-King RS, Benashski SE, McCaffery JM, Goldstein LS, King SM. Drosophila roadblock and Chlamydomonas Lc7. J Cell Biol 1999. [DOI: 10.1083/jcb.146.1.165] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Eukaryotic organisms utilize microtubule-dependent motors of the kinesin and dynein superfamilies to generate intracellular movement. To identify new genes involved in the regulation of axonal transport in Drosophila melanogaster, we undertook a screen based upon the sluggish larval phenotype of known motor mutants. One of the mutants identified in this screen, roadblock (robl), exhibits diverse defects in intracellular transport including axonal transport and mitosis. These defects include intra-axonal accumulations of cargoes, severe axonal degeneration, and aberrant chromosome segregation. The gene identified by robl encodes a 97–amino acid polypeptide that is 57% identical (70% similar) to the 105–amino acid Chlamydomonas outer arm dynein–associated protein LC7, also reported here. Both robl and LC7 have homology to several other genes from fruit fly, nematode, and mammals, but not Saccharomyces cerevisiae. Furthermore, we demonstrate that members of this family of proteins are associated with both flagellar outer arm dynein and Drosophila and rat brain cytoplasmic dynein. We propose that roadblock/LC7 family members may modulate specific dynein functions.
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Affiliation(s)
- Aaron B. Bowman
- Howard Hughes Medical Institute, Division of Cellular and Molecular Medicine, Department of Pharmacology, University of California San Diego, La Jolla, California 92093-0683
| | - Ramila S. Patel-King
- Department of Biochemistry, University of Connecticut Health Center, Farmington, Connecticut 06032-3305
| | - Sharon E. Benashski
- Department of Biochemistry, University of Connecticut Health Center, Farmington, Connecticut 06032-3305
| | - J. Michael McCaffery
- Integrated Imaging Center, Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218
| | - Lawrence S.B. Goldstein
- Howard Hughes Medical Institute, Division of Cellular and Molecular Medicine, Department of Pharmacology, University of California San Diego, La Jolla, California 92093-0683
| | - Stephen M. King
- Department of Biochemistry, University of Connecticut Health Center, Farmington, Connecticut 06032-3305
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Habura A, Tikhonenko I, Chisholm RL, Koonce MP. Interaction mapping of a dynein heavy chain. Identification of dimerization and intermediate-chain binding domains. J Biol Chem 1999; 274:15447-53. [PMID: 10336435 DOI: 10.1074/jbc.274.22.15447] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cytoplasmic dynein is a multisubunit microtubule-based motor protein that is involved in several eukaryotic cell motilities. Two dynein heavy chains each form a motor domain that connects to a common cargo-binding tail. Although this tail domain is composed of multiple polypeptides, subunit organization within this region is poorly understood. Here we present an in vitro dissection of the tail-forming region of the dynein heavy chain from Dictyostelium. Our work identifies a sequence important for dimerization and for binding the dynein intermediate chain. The core of this motif localizes within an approximately 150-amino acid region that is strongly conserved among other cytoplasmic dyneins. This level of conservation does not extend to the axonemal dynein heavy chains, suggesting functional differences between the two. Dimerization appears to occur through a different mechanism than the heavy chain-intermediate chain interaction. We corroborate the in vitro interactions with in vivo expression of heavy chain fragments in Dictyostelium. Fragments lacking the interaction domain express well, without an obvious phenotype. On the other hand, the region crucial for both interactions appears to be lethal when overexpressed.
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Affiliation(s)
- A Habura
- Division of Molecular Medicine, Wadsworth Center, Empire State Plaza, Albany, New York 12201-0509, USA
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41
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Hafalla JC, Alamares JG, Acosta LP, Dunne DW, Ramirez BL, Santiago ML. Molecular identification of a 21.7 kDa schistosoma japonicum antigen as a target of the human IgE response. Mol Biochem Parasitol 1999; 98:157-61. [PMID: 10029318 DOI: 10.1016/s0166-6851(98)00160-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- J C Hafalla
- Schistosomiasis Study Group, Research Institute for Tropical Medicine, Alabang, Muntinlupa, Philippines.
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