1
|
de Oliveira Silva A, Aliyeva-Schnorr L, Wirsel SGR, Deising HB. Fungal Pathogenesis-Related Cell Wall Biogenesis, with Emphasis on the Maize Anthracnose Fungus Colletotrichum graminicola. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11070849. [PMID: 35406829 PMCID: PMC9003368 DOI: 10.3390/plants11070849] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/14/2022] [Accepted: 03/17/2022] [Indexed: 05/25/2023]
Abstract
The genus Colletotrichum harbors many plant pathogenic species, several of which cause significant yield losses in the field and post harvest. Typically, in order to infect their host plants, spores germinate, differentiate a pressurized infection cell, and display a hemibiotrophic lifestyle after plant invasion. Several factors required for virulence or pathogenicity have been identified in different Colletotrichum species, and adaptation of cell wall biogenesis to distinct stages of pathogenesis has been identified as a major pre-requisite for the establishment of a compatible parasitic fungus-plant interaction. Here, we highlight aspects of fungal cell wall biogenesis during plant infection, with emphasis on the maize leaf anthracnose and stalk rot fungus, Colletotrichum graminicola.
Collapse
|
2
|
Abstract
Filamentous fungi are a large and ancient clade of microorganisms that occupy a broad range of ecological niches. The success of filamentous fungi is largely due to their elongate hypha, a chain of cells, separated from each other by septa. Hyphae grow by polarized exocytosis at the apex, which allows the fungus to overcome long distances and invade many substrates, including soils and host tissues. Hyphal tip growth is initiated by establishment of a growth site and the subsequent maintenance of the growth axis, with transport of growth supplies, including membranes and proteins, delivered by motors along the cytoskeleton to the hyphal apex. Among the enzymes delivered are cell wall synthases that are exocytosed for local synthesis of the extracellular cell wall. Exocytosis is opposed by endocytic uptake of soluble and membrane-bound material into the cell. The first intracellular compartment in the endocytic pathway is the early endosomes, which emerge to perform essential additional functions as spatial organizers of the hyphal cell. Individual compartments within septated hyphae can communicate with each other via septal pores, which allow passage of cytoplasm or organelles to help differentiation within the mycelium. This article introduces the reader to more detailed aspects of hyphal growth in fungi.
Collapse
|
3
|
Hill TW, Jackson-Hayes L, Wang X, Hoge BL. A mutation in the converter subdomain of Aspergillus nidulans MyoB blocks constriction of the actomyosin ring in cytokinesis. Fungal Genet Biol 2015; 75:72-83. [PMID: 25645080 DOI: 10.1016/j.fgb.2015.01.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 01/11/2015] [Accepted: 01/22/2015] [Indexed: 12/17/2022]
Abstract
We have identified a mutant allele of the Aspergillus nidulans homologue of myosin II (myoB; AN4706), which prevents normal septum formation. This is the first reported myosin II mutation in a filamentous fungus. Strains expressing the myoB(G843D) allele produce mainly aberrant septa at 30 °C and are completely aseptate at temperatures above 37 °C. Conidium formation is greatly reduced at 30 °C and progressively impaired with increasing temperature. Sequencing of the myoB(G843D) allele identified a point mutation predicted to result in a glycine-to-aspartate amino acid substitution at residue 843 in the myosin II converter domain. This residue is conserved in all fungal, plant, and animal myosin sequences that we have examined. The mutation does not prevent localization of the myoB(G843D) gene product to contractile rings, but it does block ring constriction. MyoB(G843D) rings at sites of abortive septation disassemble after an extended period and dissipate into the cytoplasm. During contractile ring formation, both wild type and mutant MyoB::GFP colocalize with actin--an association that begins at the pre-ring "string" stage. Down-regulation of wild-type myoB expression under control of the alcA promoter blocks septation but does not prevent actin from aggregating at putative septation sites--the actin rings, however, do not fully coalesce. Both septation and targeting of MyoB are blocked by disruption of filamentous actin using latrunculin B. We propose a model in which myosin assembly at septation sites depends upon the presence of F-actin, but assembly of the actin component of contractile rings depends upon normal levels of myosin only for the final stages of ring compaction.
Collapse
Affiliation(s)
- Terry W Hill
- Department of Biology, Rhodes College, Memphis, TN 38112, USA.
| | | | - Xiao Wang
- Department of Biology, Rhodes College, Memphis, TN 38112, USA
| | - Brianna L Hoge
- Department of Biology, Rhodes College, Memphis, TN 38112, USA
| |
Collapse
|
4
|
Cai G, Parrotta L, Cresti M. Organelle trafficking, the cytoskeleton, and pollen tube growth. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2015; 57:63-78. [PMID: 25263392 DOI: 10.1111/jipb.12289] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 09/23/2014] [Indexed: 06/03/2023]
Abstract
The pollen tube is fundamental for the reproduction of seed plants. Characteristically, it grows relatively quickly and uni-directionally ("polarized growth") to extend the male gametophyte to reach the female gametophyte. The pollen tube forms a channel through which the sperm cells move so that they can reach their targets in the ovule. To grow quickly and directionally, the pollen tube requires an intense movement of organelles and vesicles that allows the cell's contents to be distributed to sustain the growth rate. While the various organelles distribute more or less uniformly within the pollen tube, Golgi-released secretory vesicles accumulate massively at the pollen tube apex, that is, the growing region. This intense movement of organelles and vesicles is dependent on the dynamics of the cytoskeleton, which reorganizes differentially in response to external signals and coordinates membrane trafficking with the growth rate of pollen tubes.
Collapse
Affiliation(s)
- Giampiero Cai
- Department of Life Sciences, University of Siena, Siena, 53100, Italy
| | | | | |
Collapse
|
5
|
Grolig F, Moch J, Schneider A, Galland P. Actin cytoskeleton and organelle movement in the sporangiophore of the zygomycete Phycomyces blakesleeanus. PLANT BIOLOGY (STUTTGART, GERMANY) 2014; 16 Suppl 1:167-178. [PMID: 23927723 DOI: 10.1111/plb.12065] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Accepted: 05/17/2013] [Indexed: 06/02/2023]
Abstract
Growth, photo- and gravitropism of sporangiophores of the zygomycete Phycomyces blakesleeanus occur within the apical growing zone, a cylindrical structure (diameter about 100 μm) that reaches about 1.5-2.5 mm below the tip and has growth rates up to 50 μm·min(-1) . To better understand morphogenesis and growth of the giant aerial hypha, we investigated with confocal microscopy and inhibitors the actin cytoskeleton and by in-vivo particle tracking the associated organelle movement. We found stage-1 sporangiophores (without sporangium) possess an actin cytoskeleton with polar zonation. (i) In the apex, abundant microfilaments without preferential orientation entangled numerous nuclei as well as a conspicious complex of some 200 lipid globules. Microfilament patches (≈ 1.6-μm diameter) are clustered in the tip and were found in the apical cortex, whereas short, curved microfilament bundles (≈ 2.3-μm long) prevailed in the subapex. (ii) In a transition zone downwards to the shaft, the microfilaments rearranged into a dense mat of longitudinal microfilaments that was parallel close to the periphery but more random towards the cell centre. Numerous microfilament patches were found near the cortex (≈ 10/100 μm(2) ); their number decreased rapidly in the subcortex. In contrast, the short, curved microfilament bundles were found only in the subcortex. (iii) The basal shaft segment of the sporangiophore (with central vacuole) exhibited bidirectional particle movement over long distances (velocity ≈ 2 μm·s(-1) ) along massive longitudinal, subcortical microfilament cables. The zonation of the cytoskeleton density correlated well with the local growth rates at the tip of the sporangiophore, and appears thus as a structural prerequisite for growth and bending.
Collapse
Affiliation(s)
- F Grolig
- Fachbereich Biologie, Philipps-Universität Marburg, Marburg, Germany
| | | | | | | |
Collapse
|
6
|
|
7
|
Rios L, Bachand GD. Multiplex transport and detection of cytokines using kinesin-driven molecular shuttles. LAB ON A CHIP 2009; 9:1005-1010. [PMID: 19294315 DOI: 10.1039/b816444d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The application of biomolecular active transport systems offers a potential route for downscaling multiple analyte assays for lab-on-a-chip applications. Recently, the capture and transport of a wide range of target analytes including proteins, virus particles, and DNA have been demonstrated using kinesin-driven molecular shuttles. The molecular shuttles consisted of microtubule (MT) filaments that were functionalized with either analyte-selective antibodies or complementary DNA, thus facilitating selective target capture and transport. In the present work, we have applied this microfluidic platform for the simultaneous detection of multiple target protein analytes. Multiplexing of molecular shuttles was achieved by immobilizing biotinylated antibodies against interleukin-2 (IL-2) and tumor necrosis factor-alpha (TNF-alpha) on biotinylated MTs using a streptavidin bridge. Nanocrystal quantum dots of different sizes and spectral emissions were functionalized with IL-2 and TNF-alpha antibodies to facilitate multiplexed detection. In this paper we discuss the results of selectivity and motility in single and multiplexed assays.
Collapse
Affiliation(s)
- Lynnette Rios
- Biomolecular Interfaces & Systems Department, Sandia National Laboratories, PO Box 5800, MS 1303, Albuqeurque, NM 87185-1303, USA
| | | |
Collapse
|
8
|
Cánovas D, Pérez-Martín J. Sphingolipid biosynthesis is required for polar growth in the dimorphic phytopathogen Ustilago maydis. Fungal Genet Biol 2009; 46:190-200. [DOI: 10.1016/j.fgb.2008.11.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2008] [Revised: 10/21/2008] [Accepted: 11/03/2008] [Indexed: 10/21/2022]
|
9
|
Veses V, Gow NA. Vacuolar dynamics during the morphogenetic transition inCandida albicans. FEMS Yeast Res 2008; 8:1339-48. [DOI: 10.1111/j.1567-1364.2008.00447.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
|
10
|
Greene AC, Trent AM, Bachand GD. Controlling kinesin motor proteins in nanoengineered systems through a metal-binding on/off switch. Biotechnol Bioeng 2008; 101:478-86. [DOI: 10.1002/bit.21927] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
11
|
Fischer R, Zekert N, Takeshita N. Polarized growth in fungi--interplay between the cytoskeleton, positional markers and membrane domains. Mol Microbiol 2008; 68:813-26. [PMID: 18399939 DOI: 10.1111/j.1365-2958.2008.06193.x] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
One kind of the most extremely polarized cells in nature are the indefinitely growing hyphae of filamentous fungi. A continuous flow of secretion vesicles from the hyphal cell body to the growing hyphal tip is essential for cell wall and membrane extension. Because microtubules (MT) and actin, together with their corresponding motor proteins, are involved in the process, the arrangement of the cytoskeleton is a crucial step to establish and maintain polarity. In Saccharomyces cerevisiae and Schizosaccharomyces pombe, actin-mediated vesicle transportation is sufficient for polar cell extension, but in S. pombe, MTs are in addition required for the establishment of polarity. The MT cytoskeleton delivers the so-called cell-end marker proteins to the cell pole, which in turn polarize the actin cytoskeleton. Latest results suggest that this scenario may principally be conserved from S. pombe to filamentous fungi. In addition, in filamentous fungi, MTs could provide the tracks for long-distance vesicle movement. In this review, we will compare the interaction of the MT and the actin cytoskeleton and their relation to the cortex between yeasts and filamentous fungi. In addition, we will discuss the role of sterol-rich membrane domains in combination with cell-end marker proteins for polarity establishment.
Collapse
Affiliation(s)
- Reinhard Fischer
- Department of Applied Microbiology, University of Karlsruhe, Hertzstrasse 16, D-76187 Karlsruhe, Germany
| | | | | |
Collapse
|
12
|
Malavazi I, Savoldi M, da Silva Ferreira ME, Soriani FM, Bonato PS, de Souza Goldman MH, Goldman GH. Transcriptome analysis of the Aspergillus nidulans AtmA (ATM, Ataxia-Telangiectasia mutated) null mutant. Mol Microbiol 2007; 66:74-99. [PMID: 17880424 DOI: 10.1111/j.1365-2958.2007.05885.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] [Indexed: 12/12/2022]
Abstract
ATM is a phosphatidyl-3-kinase-related protein kinase that functions as a central regulator of DNA damage response in eukaryotes. In humans, mutations in ATM cause the devastating neurodegenerative disease Ataxia-Telangiectasia. Previously, we characterized the homologue of ATM (AtmA) in the filamentous fungus Aspergillus nidulans. In addition to its expected role in the DNA damage response, we found that AtmA is also required for polarized hyphal growth. Our results suggested that AtmA probably regulates the function and/or localization of landmark proteins required for the formation of a polarity axis. Here, we extended these studies by investigating which pathways are influenced by AtmA during proliferation and polar growth by comparatively determining the transcriptional profile of A. nidulans wild-type and DeltaatmA mutant strains in different growth conditions. Our results indicate an important role of the pentose phosphate pathway in the fungal proliferation during endogenous DNA damage and polar growth monitored by the AtmA kinase. Furthermore, we identified several genes that have decreased mRNA expression in the DeltaatmA mutant that are involved in the formation of a polarized hyphae and control of polar growth; in the synthesis of phosphatidic acid (e.g. phospholipase D); in the ergosterol biosynthesis (plasma membrane microdomains, lipid rafts); and in intracellular trafficking.
Collapse
Affiliation(s)
- Iran Malavazi
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | | | | | | | | | | | | |
Collapse
|
13
|
Redowicz MJ. Unconventional myosins in muscle. Eur J Cell Biol 2007; 86:549-58. [PMID: 17662501 DOI: 10.1016/j.ejcb.2007.05.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Revised: 05/30/2007] [Accepted: 05/31/2007] [Indexed: 10/23/2022] Open
Abstract
Myosins, actin-based molecular motors originally isolated from muscle tissues, are ubiquitously expressed in all eukaryotic cells. They are involved in a panoply of cellular functions, including cell migration, intracellular trafficking, adhesion, and cytokinesis. Several unconventional myosins belonging to classes I, V, VI, VII, IX, and XVIII have been detected in myogenic cells and/or adult muscle where they seem to play important roles in muscle functioning and/or differentiation. For example, a point mutation within the myosin VI gene leads to a cardiac dysfunction, and myosin XVIIIB (expressed predominantly in striated muscle) may be involved in muscle gene transcription. This review summarizes data addressing the functioning of these unconventional myosins in muscle and/or myogenic cells.
Collapse
Affiliation(s)
- Maria Jolanta Redowicz
- Department of Biochemistry, Nencki Institute of Experimental Biology, 3 Pasteur Street, PL 02-093 Warsaw, Poland.
| |
Collapse
|
14
|
Abstract
Fungi invade substrates, such as host tissues, through hyphal tip growth. This article focuses on the corn smut fungus Ustilago maydis, in which tip growth and pathogenicity involve apical endocytic recycling by early endosomes. These organelles rapidly move bi-directionally along microtubules and this movement is mediated by opposing molecular motors. This motility seems to be essential for extended hyphal growth, possibly because it focuses the endocytic machinery at the hyphal tip and mediates communication between the tip and the sub-apical nucleus.
Collapse
Affiliation(s)
- Gero Steinberg
- Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch Strabe D-35043 Marburg, Germany.
| |
Collapse
|
15
|
Steinberg G. Preparing the way: fungal motors in microtubule organization. Trends Microbiol 2006; 15:14-21. [PMID: 17129730 DOI: 10.1016/j.tim.2006.11.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 09/27/2006] [Accepted: 11/15/2006] [Indexed: 12/24/2022]
Abstract
Fungal growth, development and pathogenicity require hyphal tip growth, which is supported by polar exocytosis at the expanding growth region. It is assumed that molecular motors transport growth supplies along the fibrous elements of the cytoskeleton, such as microtubules, to the hyphal apex. Recent advances in live-cell imaging of fungi revealed additional roles for motors in organizing their own tracks. These unexpected roles of the molecular motors are modifying microtubule dynamics directly, targeting stability-determining factors to microtubule plus ends, and transporting and arranging already-assembled microtubules.
Collapse
Affiliation(s)
- Gero Steinberg
- Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Strasse, D-35043 Marburg, Germany.
| |
Collapse
|
16
|
Wright GD, Arlt J, Poon WCK, Read ND. Optical tweezer micromanipulation of filamentous fungi. Fungal Genet Biol 2006; 44:1-13. [PMID: 16908207 DOI: 10.1016/j.fgb.2006.07.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 07/03/2006] [Accepted: 07/05/2006] [Indexed: 11/21/2022]
Abstract
Optical tweezers have been little used in experimental studies on filamentous fungi. We have built a simple, compact, easy-to-use, safe and robust optical tweezer system that can be used with brightfield, phase contrast, differential interference contrast and fluorescence optics on a standard research grade light microscope. We have used this optical tweezer system in a range of cell biology applications to trap and micromanipulate whole fungal cells, organelles within cells, and beads. We have demonstrated how optical tweezers can be used to: unambiguously determine whether hyphae are actively homing towards each other; move the Spitzenkörper and change the pattern of hyphal morphogenesis; make piconewton force measurements; mechanically stimulate hyphal tips; and deliver chemicals to localized regions of hyphae. Significant novel experimental findings from our study were that germ tubes generated significantly smaller growth forces than leading hyphae, and that both hyphal types exhibited growth responses to mechanical stimulation with optically trapped polystyrene beads. Germinated spores that had been optically trapped for 25min exhibited no deleterious effects with regard to conidial anastomosis tube growth, homing or fusion.
Collapse
Affiliation(s)
- Graham D Wright
- Fungal Cell Biology Group, Institute of Cell Biology, University of Edinburgh, Rutherford Building, Edinburgh, UK
| | | | | | | |
Collapse
|
17
|
Darrah PR, Tlalka M, Ashford A, Watkinson SC, Fricker MD. The vacuole system is a significant intracellular pathway for longitudinal solute transport in basidiomycete fungi. EUKARYOTIC CELL 2006; 5:1111-25. [PMID: 16835455 PMCID: PMC1489287 DOI: 10.1128/ec.00026-06] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2006] [Accepted: 04/24/2006] [Indexed: 11/20/2022]
Abstract
Mycelial fungi have a growth form which is unique among multicellular organisms. The data presented here suggest that they have developed a unique solution to internal solute translocation involving a complex, extended vacuole. In all filamentous fungi examined, this extended vacuole forms an interconnected network, dynamically linked by tubules, which has been hypothesized to act as an internal distribution system. We have tested this hypothesis directly by quantifying solute movement within the organelle by photobleaching a fluorescent vacuolar marker. Predictive simulation models were then used to determine the transport characteristics over extended length scales. This modeling showed that the vacuolar organelle forms a functionally important, bidirectional diffusive transport pathway over distances of millimeters to centimeters. Flux through the pathway is regulated by the dynamic tubular connections involving homotypic fusion and fission. There is also a strongly predicted interaction among vacuolar organization, predicted diffusion transport distances, and the architecture of the branching colony margin.
Collapse
Affiliation(s)
- P R Darrah
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, United Kingdom
| | | | | | | | | |
Collapse
|
18
|
Lenz JH, Schuchardt I, Straube A, Steinberg G. A dynein loading zone for retrograde endosome motility at microtubule plus-ends. EMBO J 2006; 25:2275-86. [PMID: 16688221 PMCID: PMC1478194 DOI: 10.1038/sj.emboj.7601119] [Citation(s) in RCA: 188] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2006] [Accepted: 04/05/2006] [Indexed: 12/24/2022] Open
Abstract
In the fungus Ustilago maydis, early endosomes move bidirectionally along microtubules (MTs) and facilitate growth by local membrane recycling at the tip of the infectious hypha. Here, we set out to elucidate the molecular mechanism of this process. We show that endosomes travel by Kinesin-3 activity into the hyphal apex, where they reverse direction and move backwards in a dynein-dependent manner. Our data demonstrate that dynein, dynactin and Lis1 accumulate at MT plus-ends within the hyphal tip, where they provide a reservoir of inactive motors for retrograde endosome transport. Consistently, endosome traffic is abolished after depletion of the dynein activator Lis1 and in Kinesin-1 null mutants, which was due to a defect in targeting of dynein and dynactin to the apical MT plus-ends. Furthermore, biologically active GFP-dynein travels on endosomes in retrograde and not in anterograde direction. Surprisingly, a CLIP170 homologue was neither needed for dynein localization nor for endosome transport. These results suggest an apical dynein loading zone in the hyphal tip, which ensure that endosomes reach the expanding growth region before they reverse direction.
Collapse
Affiliation(s)
- J H Lenz
- Max-Planck-Institut für terrestrische Mikrobiologie, Marburg, Germany
| | - I Schuchardt
- Max-Planck-Institut für terrestrische Mikrobiologie, Marburg, Germany
| | - A Straube
- Max-Planck-Institut für terrestrische Mikrobiologie, Marburg, Germany
| | - G Steinberg
- Max-Planck-Institut für terrestrische Mikrobiologie, Marburg, Germany
- Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Straße, 35043 Marburg, Germany. Tel.: +49 6421 178 530; Fax: +49 6421 599; E-mail:
| |
Collapse
|
19
|
Goes TS, Goes VS, Kalapothakis E, Leite MF, Goes AM. Identification of immunogenic proteins from Paracoccidioides brasiliensis antigenic fractions F0, FII and FIII. Immunol Lett 2005; 101:24-31. [PMID: 15904973 DOI: 10.1016/j.imlet.2005.04.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2005] [Indexed: 11/21/2022]
Abstract
Paracoccidioides brasiliensis causes a chronic granulomatous mycosis prevalent in South America, and cell-mediated immunity is the principal mode of protection against this fungal infection. In this context, one of the strategies to discover proteins that are target of an effective immune response against P. brasiliensis is the partial sequencing of cDNA from an expression library previously screened with immunoglobulins (Ig) to generate antigen sequence tags (AST). In the present work, a P. brasiliensis yeast cDNA expression library was screened with affinity chromatography-purified IgG from rabbit sera immunized with P. brasiliensis antigenic fractions (F0, FII or FIII) or from paracoccidioidomycosis (PCM) patient sera by indirect ELISA. From 119 clones selected by the immunoscreening procedure, 40% were recognized by IgG from PCM patients, 25% were recognized by anti-F0, 8% were selected by anti-FII and 11% recognized by FIII specific antibodies. The remaining clones presented cross-reaction to all anti-sera tested. The AST homologies with previously reported sequences in the nonredundant GenBank at NCBI revealed high significant homology to fungal proteins of known function. One of them matched calcineurin B of Neurospora crassa with 35% identity and 55% similarity in amino acid sequence. We also identified an AST homologous to a Kinesin like protein from Ustilagus maydis and other fungi with 86% identity and 91% similarity. On the other hand, the vast majority of selected cDNA clones are new genes and represent 60% of the total. Prediction of transmembrane regions with the prediction transmembrane protein topology with a hidden markov model (TMHMM) revealed consensus sequences representing structural membrane segments in 28 encoded proteins.
Collapse
Affiliation(s)
- T S Goes
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Caixa Postal 486, CEP 31 270-901 Belo Horizonte, MG, Brazil
| | | | | | | | | |
Collapse
|
20
|
Schuchardt I, Assmann D, Thines E, Schuberth C, Steinberg G. Myosin-V, Kinesin-1, and Kinesin-3 cooperate in hyphal growth of the fungus Ustilago maydis. Mol Biol Cell 2005; 16:5191-201. [PMID: 16120650 PMCID: PMC1266418 DOI: 10.1091/mbc.e05-04-0272] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Long-distance transport is crucial for polar-growing cells, such as neurons and fungal hyphae. Kinesins and myosins participate in this process, but their functional interplay is poorly understood. Here, we investigate the role of kinesin motors in hyphal growth of the plant pathogen Ustilago maydis. Although the microtubule plus-ends are directed to the hyphal tip, of all 10 kinesins analyzed, only conventional kinesin (Kinesin-1) and Unc104/Kif1A-like kinesin (Kinesin-3) were up-regulated in hyphae and they are essential for extended hyphal growth. deltakin1 and deltakin3 mutant hyphae grew irregular and remained short, but they were still able to grow polarized. No additional phenotype was detected in deltakin1rkin3 double mutants, but polarity was lost in deltamyo5rkin1 and deltamyo5rkin3 mutant cells, suggesting that kinesins and class V myosin cooperate in hyphal growth. Consistent with such a role in secretion, fusion proteins of green fluorescent protein and Kinesin-1, Myosin-V, and Kinesin-3 accumulate in the apex of hyphae, a region where secretory vesicles cluster to form the fungal Spitzenkörper. Quantitative assays revealed a role of Kin3 in secretion of acid phosphatase, whereas Kin1 was not involved. Our data demonstrate that just two kinesins and at least one myosin support hyphal growth.
Collapse
Affiliation(s)
- Isabel Schuchardt
- Max-Planck-Institut für Terrestrische Mikrobiologie, Karl-von-Frisch-Strasse, D-35043 Marburg, Germany
| | | | | | | | | |
Collapse
|
21
|
Kawano CY, Said S. Hyperbranching induced by cold-shock orsnow-flake mutation inNeurospora crassa is prevented by addition of exogenous calcium. J Basic Microbiol 2005; 45:199-206. [PMID: 15900541 DOI: 10.1002/jobm.200410496] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Hyphal tip growth is a highly polarized process of cell extension, which may be affected by chemical and physical stress. Neurospora crassa exposed to cold-shock lost its polarized growth and dichotomous branches were detected. These effects were not observed in the presence of 500 mM Ca2+. We compared here the morphological pattern of a snow-flake mutant (sn) and the wild-type (wt) exposed to 4 degrees C. Hyphal morphology, nuclei, actin and microtubule distribution were analyzed. No effects on sn hyphal morphology were detected at 4 degrees C. Exogenous Ca2+ converted sn to an essentially wt appearance. The results presented here suggest that sn mutation and cold-shock treatment have affected Ca2+ influx since addition of this cation to sn (30 degrees C) and to wt (4 degrees C) maintained polarized growth and normal nuclear and microtubules distribution.
Collapse
Affiliation(s)
- Cristina Y Kawano
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Avenida Zeferino Vaz s/n, CEP 14040-903 - Ribeirão Preto - SP, Brasil
| | | |
Collapse
|
22
|
Fuchs U, Manns I, Steinberg G. Microtubules are dispensable for the initial pathogenic development but required for long-distance hyphal growth in the corn smut fungus Ustilago maydis. Mol Biol Cell 2005; 16:2746-58. [PMID: 15829564 PMCID: PMC1142421 DOI: 10.1091/mbc.e05-03-0176] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2005] [Revised: 03/31/2005] [Accepted: 04/01/2005] [Indexed: 11/11/2022] Open
Abstract
Fungal pathogenicity often involves a yeast-to-hypha transition, but the structural basis for this dimorphism is largely unknown. Here we analyze the role of the cytoskeleton in early steps of pathogenic development in the corn pathogen Ustilago maydis. On the plant yeast-like cells recognize each other, undergo a cell cycle arrest, and form long conjugation hyphae, which fuse and give rise to infectious filaments. F-actin is essential for polarized growth at all these stages and for cell-cell fusion. Furthermore, F-actin participates in pheromone secretion, but not perception. Although U. maydis contains prominent tubulin arrays, microtubules are neither required for cell-cell recognition, nor for cell-cell fusion, and have only minor roles in morphogenesis of yeast-like cells. Without microtubules hyphae are formed, albeit at 60% reduced elongation rates, but they reach only approximately 50 mum in length and the nucleus fails to migrate into the hypha. A similar phenotype is found in dynein mutants that have a nuclear migration defect and stop hyphal elongation at approximately 50 mum. These results demonstrate that microtubules are dispensable for polarized growth during morphological transition, but become essential in long-distance hyphal growth, which is probably due to their role in nuclear migration.
Collapse
Affiliation(s)
- Uta Fuchs
- Max-Planck-Institut für terrestrische Mikrobiologie, D-35043 Marburg, Germany
| | | | | |
Collapse
|
23
|
Liu H, Kauffman S, Becker JM, Szaniszlo PJ. Wangiella (Exophiala) dermatitidis WdChs5p, a class V chitin synthase, is essential for sustained cell growth at temperature of infection. EUKARYOTIC CELL 2004; 3:40-51. [PMID: 14871935 PMCID: PMC329517 DOI: 10.1128/ec.3.1.40-51.2004] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The chitin synthase structural gene WdCHS5 was isolated from the black fungal pathogen of humans Wangiella dermatitidis. Sequence analysis revealed that the gene has a myosin motor-like-encoding region at its 5' end and a chitin synthase (class V)-encoding region at its 3' end. Northern blotting showed that WdCHS5 is expressed at high levels under conditions of stress. Analysis of the 5' upstream region of WdCHS5 fused to a reporter gene indicated that one or more of the potential regulatory elements present may have contributed to the high expression levels. Disruption of WdCHS5 produced mutants that grow normally at 25 degrees C but have severe growth and cellular abnormalities at 37 degrees C. Osmotic stabilizers, such as sorbitol and sucrose, rescued the wild-type phenotype, which indicated that the loss of WdChs5p causes cell wall integrity defects. Animal survival tests with a mouse model of acute infection showed that all wdchs5Delta mutants are less virulent than the parental strain. Reintroduction of the WdCHS5 gene into the wdchs5Delta mutants abolished the temperature-sensitive phenotype and reestablished their virulence. We conclude that the product of WdCHS5 is required for the sustained growth of W. dermatitidis at 37 degrees C and is of critical importance to its virulence.
Collapse
Affiliation(s)
- Hongbo Liu
- Section of Molecular Genetics and Microbiology, School of Biological Science and Institute of Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA
| | | | | | | |
Collapse
|
24
|
Matsui Y. Polarized distribution of intracellular components by class V myosins in Saccharomyces cerevisiae. ACTA ACUST UNITED AC 2004; 229:1-42. [PMID: 14669953 DOI: 10.1016/s0074-7696(03)29001-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
The budding yeast Saccharomyces cerevisiae has three classes of myosins corresponding to three actin structures: class I myosin for endocytic actin structure, actin patches; class II myosin for contraction of the actomyosin contractile ring around the bud neck; and class V myosin for transport along a cable-like actin structure (actin cables), extending toward the growing cortex. Myo2p and Myo4p constitute respective class V myosins as the heavy chain and, like class V myosins in other organisms, function as actin-based motors for polarized distribution of organelles and intracellular molecules. Proper distribution of organelles is essential for autonomously replicating organelles that cannot be reproduced de novo, and is also quite important for other organelles to ensure their efficient segregation and proper positioning, even though they can be newly synthesized, such as those derived from endoplasmic reticulum. In the budding yeast, microtubule-based motors play limited roles in the distribution. Instead, the actin-based motor myosins, especially Myo2p, play a major role. Studies on Myo2p have revealed a wide variety of Myo2p cargo and Myo2p-interacting proteins and have established that Myo2p interacts with cargo and transfers it along actin cables. Moreover, recent findings suggest that Myo2p has another way to distribute cargo in that Myo2p conveys the attaching cargo along the actin track. Thus, the myosin have "dual paths" for distribution of a cargo. This dual path mechanism is proposed in the last section of this review.
Collapse
Affiliation(s)
- Yasushi Matsui
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo 113-0033, Japan
| |
Collapse
|
25
|
Basse CW, Steinberg G. Ustilago maydis, model system for analysis of the molecular basis of fungal pathogenicity. MOLECULAR PLANT PATHOLOGY 2004; 5:83-92. [PMID: 20565585 DOI: 10.1111/j.1364-3703.2004.00210.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
UNLABELLED SUMMARY Ustilago maydis, a facultative biotrophic basidiomycete fungus, causes smut disease in maize. A hallmark of this disease is the induction of large plant tumours that are filled with masses of black-pigmented teliospores. During the last 15 years U. maydis has become an important model system to unravel molecular mechanisms of fungal phytopathogenicity. This review highlights recent insights into molecular mechanisms of complex signalling pathways that are involved in the transition from budding to filamentous growth and operate during the pathogenic growth phase. In addition, we describe recent progress in understanding the structural basis of morphogenesis and polar growth in different stages of U. maydis development. Finally, we present an overview of recently identified genes related to pathogenic development and summarize novel molecular and genomic approaches that are powerful tools to explore the genetic base of pathogenicity. TAXONOMY Ustilago maydis (DC) Corda (synonymous with Ustilago zeae Ung.)-Kingdom Eukaryota, Phylum Fungi, Order Basidiomycota, Family Ustilaginomycetes, Genus Ustilago. HOST RANGE Infects aerial parts of corn plants (Zea mays) and its progenitor teosinte (Zea mays ssp. parviglumis). Maize smut is distributed throughout the world. Disease symptoms: U. maydis causes chlorotic lesions in infected areas, the formation of anthocyanin pigments, necrosis, hyperplasia and hypertrophy of infected organs. Infection by U. maydis can inhibit development and lead to stunting of infected plants. A few days after infection plant tumours develop in which massive fungal proliferation and the formation of the black-pigmented, diploid teliospores occurs. Under natural conditions tumours predominantly develop on sexual organs (tassels and ears), stems and nodal shoots. Tumours may vary in size from minute pustules to several centimetres in diameter and contain up to 200 billion spores. Useful web site: http://www-genome.wi.mit.edu/annotation/fungi/ustilago_maydis/
Collapse
Affiliation(s)
- Christoph W Basse
- Max-Planck-Institute for Terrestrial Microbiology, Department of Organismic Interactions, Karl-von-Frisch Strasse, 35043 Marburg, Germany
| | | |
Collapse
|
26
|
Torralba S, Pisabarro AG, Ramírez L. Immunofluorescence microscopy of the microtubule cytoskeleton during conjugate division in the dikaryon Pleurotus ostreatusN001. Mycologia 2004. [DOI: 10.1080/15572536.2005.11832995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | | | - Lucía Ramírez
- Departamento de Producción Agraria, Universidad Pública de Navarra, E-31006 Pamplona, España
| |
Collapse
|
27
|
Weber I, Gruber C, Steinberg G. A class-V myosin required for mating, hyphal growth, and pathogenicity in the dimorphic plant pathogen Ustilago maydis. THE PLANT CELL 2003; 15:2826-42. [PMID: 14615599 PMCID: PMC282809 DOI: 10.1105/tpc.016246] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2003] [Accepted: 09/29/2003] [Indexed: 05/21/2023]
Abstract
In the early stages of plant infection, yeast-like haploid sporidia of Ustilago maydis respond to pheromone secreted by compatible partners by forming conjugation tubes. These then fuse to generate a dikaryotic hypha that forms appressoria to penetrate the host plant. As a first step toward understanding the structural requirements for these transitions, we have identified myo5, which encodes a class-V myosin. Analysis of conditional and null mutants revealed that Myo5 plays nonessential roles in cytokinesis and morphogenesis in sporidia and is required for hyphal morphology. Consistent with a role in morphogenesis, a functional green fluorescent protein-Myo5 fusion protein localized to the bud tip and the hyphal apex as well as to the septa and the spore wall during later stages of infection. However, the loss of Myo5 did not affect the tip growth of hyphae and sporidia. By contrast, Myo5 was indispensable for conjugation tube formation. Furthermore, myo5 mutants were impaired in the perception of pheromones, which indicates a particular importance of Myo5 in the mating process. Consequently, few mutant hyphae were formed that penetrated the plant epidermis but did not continue invasive growth. These results indicate a crucial role of Myo5 in the morphogenesis, dimorphic switch, and pathogenicity of U. maydis.
Collapse
Affiliation(s)
- Isabella Weber
- Max-Planck-Institut für Terrestrische Mikrobiologie, D-35043 Marburg, Germany
| | | | | |
Collapse
|
28
|
Schoch CL, Aist JR, Yoder OC, Gillian Turgeon B. A complete inventory of fungal kinesins in representative filamentous ascomycetes. Fungal Genet Biol 2003; 39:1-15. [PMID: 12742059 DOI: 10.1016/s1087-1845(03)00022-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Complete inventories of kinesins from three pathogenic filamentous ascomycetes, Botryotinia fuckeliana, Cochliobolus heterostrophus, and Gibberella moniliformis, are described. These protein sequences were compared with those of the filamentous saprophyte, Neurospora crassa and the two yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe. Data mining and phylogenetic analysis of the motor domain yielded a constant set of 10 kinesins in the filamentous fungal species, compared with a smaller set in S. cerevisiae and S. pombe. The filamentous fungal kinesins fell into nine subfamilies when compared with well-characterized kinesins from other eukaryotes. A few putative kinesins (one in B. fuckeliana and two in C. heterostrophus) could not be defined as functional, due to unorthodox organization and lack of experimental data. The broad representation of filamentous fungal kinesins across most of the known subfamilies and the ease of gene manipulation make fungi ideal models for functional and evolutionary investigation of these proteins.
Collapse
Affiliation(s)
- Conrad L Schoch
- Department of Plant Pathology, 334 Plant Science Building, Cornell University, Ithaca, NY 14853, USA
| | | | | | | |
Collapse
|
29
|
Abstract
Mitochondria are essential organelles of eukaryotic cells. They grow continuously throughout the cell cycle and are inherited by daughter cells upon cell division. Inheritance of mitochondria and maintenance of mitochondrial distribution and morphology require active transport of the organelles along the cytoskeleton and depend on membrane fission and fusion events. Many of the molecular components and cellular mechanisms mediating these complex processes have been conserved during evolution across the borders of the fungal and animal kingdoms. During the past few decades, several constituents of the cellular machinery mediating mitochondrial behavior have been identified and functionally characterized. Here, we review the contributions of fungi, with special emphasis on the filamentous fungus Neurospora crassa, to our current understanding of mitochondrial morphogenesis and inheritance.
Collapse
Affiliation(s)
- Benedikt Westermann
- Institut für Physiologische Chemie, Universität München, Butenandtstr. 5, 81377 Munich, Germany
| | | |
Collapse
|
30
|
Gupta GD, Brent Heath I. Predicting the distribution, conservation, and functions of SNAREs and related proteins in fungi. Fungal Genet Biol 2002; 36:1-21. [PMID: 12051891 DOI: 10.1016/s1087-1845(02)00017-8] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Hyphal tip growth, the hallmark of the fungi, requires highly polarized and localized exocytosis, but how this requirement is met is unknown. Members of conserved protein families called SNAREs and Rabs mediate vesicle trafficking and fusion at virtually every step of the intracellular pathway in all examined eukaryotes. We have searched the available nearly complete fungal genomes, established the presence or absence of members of the SNARE and Rab families in these genomes, and predicted their evolutionary relationships to one another. Comparisons with the extensively studied Saccharomyces cerevisiae indicate that, in general, most of the members of these families (including those involved in mediating exocytosis) are conserved. The presence of exceptional SNAREs and Rabs in some fungi that are not conserved in S. cerevisiae may be indicative of specialized steps that occur in these fungi. The implications of these findings for current tip growth models are discussed.
Collapse
Affiliation(s)
- Gagan D Gupta
- Biology Department, York University, 4700 Keele Street, Toronto, Ont., Canada M3J 1P3
| | | |
Collapse
|
31
|
Kallipolitou A, Deluca D, Majdic U, Lakämper S, Cross R, Meyhöfer E, Moroder L, Schliwa M, Woehlke G. Unusual properties of the fungal conventional kinesin neck domain from Neurospora crassa. EMBO J 2001; 20:6226-35. [PMID: 11707394 PMCID: PMC125726 DOI: 10.1093/emboj/20.22.6226] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Fungal conventional kinesins are unusually fast microtubule motor proteins. To compare the functional organization of fungal and animal conventional kinesins, a set of C-terminal deletion mutants of the Neurospora crassa conventional kinesin, NcKin, was investigated for its biochemical and biophysical properties. While the shortest, monomeric construct comprising the catalytic core and the neck-linker (NcKin343) displays very high steady-state ATPase (k(cat) = 260/s), constructs including both the full neck and adjacent hinge domains (NcKin400, NcKin433 and NcKin480) show wild-type behaviour: they are dimeric, show fast gliding and slower ATP turnover rates (k(cat) = 60-84/s), and are chemically processive. Unexpectedly, a construct (NcKin378, corresponding to Drosophila KHC381) that includes just the entire coiled-coil neck is a monomer. Its ATPase activity is slow (k(cat) = 27/s), and chemical processivity is abolished. Together with a structural analysis of synthetic neck peptides, our data demonstrate that the NcKin neck domain behaves differently from that of animal conventional kinesins and may be tuned to drive fast, processive motility.
Collapse
Affiliation(s)
| | - Dominga Deluca
- Adolf-Butenandt-Institute, Cell Biology 1b, Universität München, Schillerstrasse 42, D-80336 Munich,
Max-Planck-Insitiute for Biochemistry, Department of Bioorganic Chemistry, Am Klopferspitz 18a, D-82152 Martinsried, Institute for Molecular and Cellular Physiology, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany and Molecular Motors Group, Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 0TL, UK Corresponding author e-mail:
| | | | - Stefan Lakämper
- Adolf-Butenandt-Institute, Cell Biology 1b, Universität München, Schillerstrasse 42, D-80336 Munich,
Max-Planck-Insitiute for Biochemistry, Department of Bioorganic Chemistry, Am Klopferspitz 18a, D-82152 Martinsried, Institute for Molecular and Cellular Physiology, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany and Molecular Motors Group, Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 0TL, UK Corresponding author e-mail:
| | - Robert Cross
- Adolf-Butenandt-Institute, Cell Biology 1b, Universität München, Schillerstrasse 42, D-80336 Munich,
Max-Planck-Insitiute for Biochemistry, Department of Bioorganic Chemistry, Am Klopferspitz 18a, D-82152 Martinsried, Institute for Molecular and Cellular Physiology, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany and Molecular Motors Group, Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 0TL, UK Corresponding author e-mail:
| | - Edgar Meyhöfer
- Adolf-Butenandt-Institute, Cell Biology 1b, Universität München, Schillerstrasse 42, D-80336 Munich,
Max-Planck-Insitiute for Biochemistry, Department of Bioorganic Chemistry, Am Klopferspitz 18a, D-82152 Martinsried, Institute for Molecular and Cellular Physiology, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany and Molecular Motors Group, Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 0TL, UK Corresponding author e-mail:
| | - Luis Moroder
- Adolf-Butenandt-Institute, Cell Biology 1b, Universität München, Schillerstrasse 42, D-80336 Munich,
Max-Planck-Insitiute for Biochemistry, Department of Bioorganic Chemistry, Am Klopferspitz 18a, D-82152 Martinsried, Institute for Molecular and Cellular Physiology, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany and Molecular Motors Group, Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 0TL, UK Corresponding author e-mail:
| | | | - Günther Woehlke
- Adolf-Butenandt-Institute, Cell Biology 1b, Universität München, Schillerstrasse 42, D-80336 Munich,
Max-Planck-Insitiute for Biochemistry, Department of Bioorganic Chemistry, Am Klopferspitz 18a, D-82152 Martinsried, Institute for Molecular and Cellular Physiology, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany and Molecular Motors Group, Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 0TL, UK Corresponding author e-mail:
| |
Collapse
|
32
|
Schultz N, Onfelt A. Spindle positioning in fibroblasts supports an astral microtubule length dependent force generation at the basal membrane. CELL MOTILITY AND THE CYTOSKELETON 2001; 50:69-88. [PMID: 11746673 DOI: 10.1002/cm.1042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
V79 Chinese hamster fibroblasts that maintain an elongated shape in metaphase occur at a low frequency and often show the spindle asymmetrically positioned. We show here that this aberrant position is corrected in anaphase by an external force, pulling the spindle into place. The force was applied on astral microtubules because spindle motility was hampered when astral microtubules were poorly developed spontaneously, or destroyed by colcemid. Colcemid also abolished the observed downward positioning of centrosomes in anaphase. One pole of the spindle was usually dominant during correction, but occasionally both poles could become subject to pulling making the spindle move perpendicular to the long axis of the cell, which induced reshaping of the cell. The pulling force acted unevenly with short intervals of resting between the pulling. Spindle elongation also varied in rate but showed a different periodicity than translocation of the spindle, and therefore appeared independently regulated. The length of the spindle increased with the length of the cell, and the rate of spindle elongation and pole movement increased with distance moved, indicating that the forces mediated by astral microtubules increase with their length. Arp1/dynactin, not colocalising with tubulin, was more often continuous with microtubules in anaphase B than in metaphase, and was primarily located at the bottom of the cell. Further, shifts in the geometric gravity centre of the cell occurred in the same direction as migration of the spindle. To explain these results, we suggest that astral microtubles transiently anchored at the bottom of the cell are of particular importance for spindle translocation in fibroblasts.
Collapse
Affiliation(s)
- N Schultz
- Genetic and Cellular Toxicology, Stockholm University, Stockholm, Sweden.
| | | |
Collapse
|
33
|
Straube A, Enard W, Berner A, Wedlich-Söldner R, Kahmann R, Steinberg G. A split motor domain in a cytoplasmic dynein. EMBO J 2001; 20:5091-100. [PMID: 11566874 PMCID: PMC125636 DOI: 10.1093/emboj/20.18.5091] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The heavy chain of dynein forms a globular motor domain that tightly couples the ATP-cleavage region and the microtubule-binding site to transform chemical energy into motion along the cytoskeleton. Here we show that, in the fungus Ustilago maydis, two genes, dyn1 and dyn2, encode the dynein heavy chain. The putative ATPase region is provided by dyn1, while dyn2 includes the predicted microtubule-binding site. Both genes are located on different chromosomes, are transcribed into independent mRNAs and are translated into separate polypeptides. Both Dyn1 and Dyn2 co-immunoprecipitated and co-localized within growing cells, and Dyn1-Dyn2 fusion proteins partially rescued mutant phenotypes, suggesting that both polypeptides interact to form a complex. In cell extracts the Dyn1-Dyn2 complex dissociated, and microtubule affinity purification indicated that Dyn1 or associated polypeptides bind microtubules independently of Dyn2. Both Dyn1 and Dyn2 were essential for cell survival, and conditional mutants revealed a common role in nuclear migration, cell morphogenesis and microtubule organization, indicating that the Dyn1-Dyn2 complex serves multiple cellular functions.
Collapse
Affiliation(s)
- Anne Straube
- Institut für Genetik und Mikrobiologie, LMU, Maria-Ward-Straße 1a, D-80638 München, Germany
Present address: Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Straße, D-35043 Marburg, Germany Present address: Max-Planck-Institut für evolutionäre Anthropologie, Inselstraße 22, D-04103 Leipzig, Germany Present address: Vision in Business Ltd, 30 City Road, London EC1Y 2AY, UK Corresponding author e-mail:
| | - Wolfgang Enard
- Institut für Genetik und Mikrobiologie, LMU, Maria-Ward-Straße 1a, D-80638 München, Germany
Present address: Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Straße, D-35043 Marburg, Germany Present address: Max-Planck-Institut für evolutionäre Anthropologie, Inselstraße 22, D-04103 Leipzig, Germany Present address: Vision in Business Ltd, 30 City Road, London EC1Y 2AY, UK Corresponding author e-mail:
| | - Alexandra Berner
- Institut für Genetik und Mikrobiologie, LMU, Maria-Ward-Straße 1a, D-80638 München, Germany
Present address: Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Straße, D-35043 Marburg, Germany Present address: Max-Planck-Institut für evolutionäre Anthropologie, Inselstraße 22, D-04103 Leipzig, Germany Present address: Vision in Business Ltd, 30 City Road, London EC1Y 2AY, UK Corresponding author e-mail:
| | - Roland Wedlich-Söldner
- Institut für Genetik und Mikrobiologie, LMU, Maria-Ward-Straße 1a, D-80638 München, Germany
Present address: Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Straße, D-35043 Marburg, Germany Present address: Max-Planck-Institut für evolutionäre Anthropologie, Inselstraße 22, D-04103 Leipzig, Germany Present address: Vision in Business Ltd, 30 City Road, London EC1Y 2AY, UK Corresponding author e-mail:
| | - Regine Kahmann
- Institut für Genetik und Mikrobiologie, LMU, Maria-Ward-Straße 1a, D-80638 München, Germany
Present address: Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Straße, D-35043 Marburg, Germany Present address: Max-Planck-Institut für evolutionäre Anthropologie, Inselstraße 22, D-04103 Leipzig, Germany Present address: Vision in Business Ltd, 30 City Road, London EC1Y 2AY, UK Corresponding author e-mail:
| | - Gero Steinberg
- Institut für Genetik und Mikrobiologie, LMU, Maria-Ward-Straße 1a, D-80638 München, Germany
Present address: Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Straße, D-35043 Marburg, Germany Present address: Max-Planck-Institut für evolutionäre Anthropologie, Inselstraße 22, D-04103 Leipzig, Germany Present address: Vision in Business Ltd, 30 City Road, London EC1Y 2AY, UK Corresponding author e-mail:
| |
Collapse
|
34
|
Steinberg G, Wedlich-Söldner R, Brill M, Schulz I. Microtubules in the fungal pathogen Ustilago maydis are highly dynamic and determine cell polarity. J Cell Sci 2001; 114:609-22. [PMID: 11171329 DOI: 10.1242/jcs.114.3.609] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Many fungal pathogens undergo a yeast-hyphal transition during their pathogenic development that requires rearrangement of the cytoskeleton, followed by directed membrane traffic towards the growth region. The role of microtubules and their dynamic behavior during this process is not well understood. Here we set out to elucidate the organization, cellular role and in vivo dynamics of microtubules in the dimorphic phytopathogen Ustilago maydis. Hyphae and unbudded yeast-like cells of U. maydis contain bundles of spindle pole body-independent microtubules. At the onset of bud formation two spherical tubulin structures focus microtubules towards the growth region, suggesting that they support polar growth in G(2), while spindle pole body-nucleated astral microtubules participate in nuclear migration in M and early G(1). Conditional mutants of an essential alpha-tubulin gene from U. maydis, tub1, confirmed a role for interphase microtubules in determination of cell polarity and growth. Observation of GFP-Tub1 fusion protein revealed that spindle pole body-independent and astral microtubules are dynamic, with elongation and shrinkage rates comparable to those found in vertebrate systems. In addition, very fast depolymerization was measured within microtubule bundles. Unexpectedly, interphase microtubules underwent bending and rapid translocations within the cell, suggesting that unknown motor activities participate in microtubule organization in U. maydis. Movies available on-line: http://www.biologists.com/JCS/movies/jcs1792.html
Collapse
Affiliation(s)
- G Steinberg
- Institut für Genetik und Mikrobiologie, LMU, Maria-Ward-Strasse 1a, D-80638 Munich, Germany.
| | | | | | | |
Collapse
|
35
|
Wedlich-Söldner R, Bölker M, Kahmann R, Steinberg G. A putative endosomal t-SNARE links exo- and endocytosis in the phytopathogenic fungus Ustilago maydis. EMBO J 2000; 19:1974-86. [PMID: 10790364 PMCID: PMC305698 DOI: 10.1093/emboj/19.9.1974] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We identified a temperature-sensitive mutant of the plant pathogenic fungus Ustilago maydis that is defective in the polar distribution of cell wall components and shows abnormal morphology. The affected gene, yup1, was cloned by complementation. It encodes a putative target soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (t-SNARE), suggesting a function in membrane fusion. A Yup1-GFP fusion protein localized to vesicles that showed rapid saltatory motion along microtubules. These vesicles are part of the endocytic pathway and accumulate at sites of active growth, thereby supporting the expansion of the hyphal tip. In yup1(ts) cells, endocytosis is impaired and accumulation of Yup1-carrying endosomes at cell poles is abolished, resulting in apolar distribution of wall components and morphological alterations. This suggests that a membrane recycling process via early endosomes supports polar growth of U. maydis.
Collapse
Affiliation(s)
- R Wedlich-Söldner
- Institut für Genetik und Mikrobiologie, LMU, Maria-Ward-Strasse 1a, D-80638 München, Germany
| | | | | | | |
Collapse
|