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Nuclei of symbiotic arbuscular mycorrhizal fungi as revealed by in vivo two-photon microscopy

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Summary

The present work reports the results obtained from in vivo studies on the distribution and behavior of nuclei of two arbuscular mycorrhizal (AM) fungi growing in symbiosis with tomato root organ cultures (AM monoxenic cultures). Upon staining with 4′,6-diamidino-2-phenylindole and two-photon microscopy (2PM) observations, symbiotic thick runner hyphae appeared mostly opaque to 2PM and did not reveal nuclei within them; thin runner hyphae showed dimly stained nuclei along them, whereas nuclei were clearly visible within the branches of the so-called branched absorbing structures. When visible, nuclei appeared anchored laterally at regular intervals along the symbiotic AM extraradical hyphae. Other nuclei migrate through the hyphal central core; this migration occurs in pulses. Simultaneous observations on different areas of extraradical AM mycelium revealed the existence of lysed compartments along the fungal hyphae, containing nuclei remnants and/or chromatin masses. All these results give new insights in (i) the differential permeability of AM hyphae in the symbiotic versus the asymbiotic state; (ii) the behavior and distribution of nuclei along the symbiotic extraradical mycelium; (iii) the occurrence of ageing events within the AM fungal colony; and (iv) the existence of “healing” mechanisms aiming to restrict the damage induced by such ageing or lytic events. An AM fungal strategy for hyphal survival under adverse conditions is also suggested.

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Abbreviations

AM:

fungi arbuscular-mycorrhizal fungi

DAPI:

4′,6-diamidino-2-phenylindole

2PM:

two-photon microscopy

PMT:

photomultiplier tube

References

  • Azcón-Aguilar C, Bago B (1994) Physiological characteristics of the host plant promoting an undisturbed functioning of the mycor-rhizal symbiosis. In: Gianinazzi S, Schüepp H (eds) Impact of arbuscular mycorrhizas on sustainable agriculture and natural ecosystems. Birkhäuser, Basel, pp 47–60

    Google Scholar 

  • — —, Barea JM (1998) Saprophitic growth of AMF. In: Varma, A, Hock B (eds) Mycorrhiza: structure, function, molecular biology and biotechnology, 2nd edn. Springer, Berlin Heidelberg New York Tokyo, pp 391–407

    Google Scholar 

  • Bago B, Bentivenga SP, Brenac V, Dodd JC, Fiché Y, Simon L (1998a) Molecular analysis ofGigaspora (Glomales, Gigasporaceae). New Phytol 139: 581–588

    Article  CAS  Google Scholar 

  • —, Zipfel W, Williams RC, Chamberland H, Lafontaine J-G, Webb WW, Piché Y (1998b) In vivo studies on the nuclear behavior of the arbuscular mycorrhizal fungusGigaspora rosea grown under axenic conditions. Protoplasma 203: 1–15

    Article  Google Scholar 

  • —, Azcón-Aguilar C, Piché Y (1998e) Architecture and developmental dynamics of the external mycelium of the arbuscular mycorrhizal fungusGlomus intraradices grown under monoxenic conditions. Mycologia 90: 52–62

    Article  Google Scholar 

  • — —, Goulet A, Piché Y (1998d) Branched absorbing structures (BAS): a feature of the extraradical mycelium of symbiotic arbuscular mycorrhizal fungi. New Phytol 139: 375–388

    Article  Google Scholar 

  • Balestrini R, Bianciotto V, Bonfante-Fasolo P (1992) Nuclear architecture and DNA location in two VAM fungi. Mycorrhiza 1: 105–112

    Article  Google Scholar 

  • Bécard G, Fortin A (1988) Early events of vesicular-arbuscular mycorrhiza formation on Ri T-DNA transformed roots. New Phytol 108: 211–218

    Article  Google Scholar 

  • Beckwith SM, Roghi CH, Liu B, Morris NR (1998) The “8-kD” cytoplasmic dynein light chain is required for nuclear migration and for dynein heavy chain localization inAspergillus nidulans. J Cell Biol 143: 1239–1247

    Article  PubMed  Google Scholar 

  • Bianciotto V, Bonfante P (1992) Quantification of the nuclear DNA content of two arbuscular mycorrhizal fungi. Mycol Res 96: 1071–1076

    Article  Google Scholar 

  • —, Barbiero G, Bonfante P (1995) Analysis of the cell cycle in an arbuscular mycorrhizal fungus by flow cytometry and bromodeoxiuridine labelling. Protoplasma 188: 161–169

    Article  Google Scholar 

  • Bonfante P, Perotto S (1995) Strategies of arbuscular mycorrhizal fungi when infecting host plants. New Phytol 130: 3–21

    Article  Google Scholar 

  • Bonfante-Fasolo P, Berta G, Fusconi A (1987) Distribution of nuclei in a VAM during its symbiotic phase. Trans Br Mycol Soc 88: 263–266

    Article  Google Scholar 

  • Chiu SW (1996) Nuclear changes during fungal development. In: Chiu SW, Moore D (eds) Patterns in fungal development. Cambridge University Press, Cambridge, pp 105–125

    Google Scholar 

  • Denk W, Piston DN, Webb WW (1995) Two-photon molecular excitation in laser scanning fluorescence microscopy. In: Pawley JB (ed) Handbook of biological confocal microscopy. Plenum, New York, pp 445–458

    Google Scholar 

  • —, Strickler JH, Webb WW (1990) Two-photon laser scanning fluorescence microscopy. Science 248: 73–76

    Article  PubMed  CAS  Google Scholar 

  • Fencl Z (1978) Cell ageing and autolysis. In: Smith JE, Berry DR (eds) The filamentous fungi, vol 3: developmental mycology. Halsted Press, New York, pp 389–405

    Google Scholar 

  • Gerdemann JW (1955) Wound healing of hyphae in a phycomycetous mycorrhizal fungus. Mycologia 47: 916–918

    Article  Google Scholar 

  • —, Nicolson JH (1963) Spores of mycorrhizalEndogone species extracted from soil by wet-sieving and decanting. Trans Br Mycol Soc 46: 235–244

    Google Scholar 

  • Gianinazzi-Pearson V, Gianinazzi S (1989) Cellular and genetical aspects of interactions between host and fungal symbionts in mycorrhizae. Genome 31: 336–341

    Google Scholar 

  • —, Gollotte A, Lherminier J, Tisserant B, Franken P, Dumas-Gaudot E, Lemoine MC, van Tuinen D, Gianinazzi S (1995) Cellular and molecular approaches in the characterization of symbiotic events in functional arbuscular mycorrhizal associations. Can J Bot 73 Suppl 1: 526–532

    Article  Google Scholar 

  • Harrison MJ (1997) The arbuscular mycorrhizal symbiosis: an underground association. Trends Plant Sci 2: 54–60

    Article  Google Scholar 

  • Jasper DA, Abbott LK, Robson AD (1989) Hyphae of vesiculararbuscular mycorrhizal fungus maintain infectivity in dry soil, except when the soil is disturbed. New Phytol 112: 101–107

    Article  Google Scholar 

  • Kapuscinski J (1995) DAPI: a DNA-specific fluorescent probe. Biotech Histochem 70: 220–233

    Article  PubMed  CAS  Google Scholar 

  • Logi C, Sbrana C, Giovannetti M (1998) Cellular events involved in survival of individual arbuscular mycorrhizal symbionts growing in the absence of the host. Appl Environ Microbiol 64: 3473–3479

    PubMed  CAS  Google Scholar 

  • Marbach K, Stahl U (1994) Senescence of mycelia. In: Wessels JGH, Meinhardt F (eds) The Mycota I: growth, differentiation and sexuality. Springer, Berlin Heidelberg New York Tokyo, pp 195–210

    Google Scholar 

  • Morris NR, Efimov VP, Xiang X (1998) Nuclear migration, nucleokinesis and lissencephaly. Trends Cell Biol 8: 467–470

    Article  PubMed  CAS  Google Scholar 

  • Mosse B (1962) The establishment of vesicular-arbuscular mycorrhiza under aseptic conditions. J Gen Microbiol 27: 509–520

    PubMed  CAS  Google Scholar 

  • — (1988) Some studies related to “independent” growth of vesicular-arbuscular endophytes. Can J Bot 66: 2533–2540

    Article  Google Scholar 

  • Piston DW, Masters BR, Webb WW (1995) Three-dimensionally resolved NAD(P)H cellular redox imaging of the in situ cornea with two photon excitation laser scanning microscopy. J Microsc 178: 20–27

    PubMed  CAS  Google Scholar 

  • Plamann M, Minke PF, Tinsley JH, Bruno KS (1994) Cytoplasmic dynein and actin-related protein are required for normal nuclear distribution in filamentous fungi. J Cell Biol 127: 139–149

    Article  PubMed  CAS  Google Scholar 

  • Simon L, Bousquet J, Lévesque R, Lalonde M (1993) Origin and diversification of endomycorrhizal fungi and coincidence with vascular land plants. Nature 363: 67–69

    Article  Google Scholar 

  • Smith SE, Read DJ (1997) Mycorrhizal symbiosis. Academic Press, San Diego

    Google Scholar 

  • Suelmann R, Sievers N, Galetzka D, Robertson L, Timberlake WE, Fischer R (1998) Increased nuclear traffic chaos inAspergillus nidulans: molecular characterization of apsB and in vivo observation of nuclear behaviour. Mol Microbiol 30: 831–842

    Article  PubMed  CAS  Google Scholar 

  • Taylor TN, Remy W, Hass H, Kerp H (1995) Fossil arbuscular mycorrhizae from the early devonian. Mycologia 87: 560–573

    Article  Google Scholar 

  • Warner A, Mosse B (1980) Independent spread of vesiculararbuscular mycorrhizal fungi in soil. Trans Br Mycol Soc 74: 407–410

    Article  Google Scholar 

  • Williams RM, Piston DW, Webb WW (1994) Two-photon molecular excitation provides intrinsic 3-dimensional resolution for laserbased microscopy and microphotochemistry. FASEB J 8: 804–813

    PubMed  CAS  Google Scholar 

  • Xu C, Webb WW (1996) Measurement of two-photon excitation cross sections of molecular fluorophores with data from 690 to 1050 nm. J Opt Soc Am B 13: 481–491

    Article  CAS  Google Scholar 

  • —, Zipfel W, Shear JB, Williams RM, Webb WW (1996) Multiphoton fluorescence excitation: new spectral windows for biological nonlinear microscopy. Proc Natl Acad Sci USA 93: 10763–10768

    Article  PubMed  CAS  Google Scholar 

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Author notes

  1. B. Bago

    Present address: U.S. Department of Agriculture, Eastern Regional Research Center, ARS, 600 E. Mermaid Lane, 19038, Wyndmoor, PA, USA

Authors and Affiliations

  1. Centre de Recherche en Biologie Forestière, Université Laval, Ste-Foy, Québec

    B. Bago & Y. Piché

  2. Applied and Engineering Physics, Cornell University, Ithaca, New York

    W. Zipfel & R. M. Williams

Authors
  1. B. Bago
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  2. W. Zipfel
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  3. R. M. Williams
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  4. Y. Piché
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Correspondence to B. Bago.

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Bago, B., Zipfel, W., Williams, R.M. et al. Nuclei of symbiotic arbuscular mycorrhizal fungi as revealed by in vivo two-photon microscopy. Protoplasma 209, 77–89 (1999). https://doi.org/10.1007/BF01415703

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  • DOI: https://doi.org/10.1007/BF01415703

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