Skip to main content
Log in

In vivo studies on the nuclear behavior of the arbuscular mycorrhizal fungus Gigaspora rosea grown under axenic conditions

  • Original Papers
  • Published:
Protoplasma Aims and scope Submit manuscript

Summary

The distribution and fate of nuclei of the arbuscular-my-corrhizal fungus Gigaspora rosea during late stages of axenic cultures were studied in fixed cultures by transmitted light, conventional and confocal laser scanning microscopy, and in live cultures with two-photon fluorescence microscopy. Mature specimens not yet showing apical septation displayed oval-shaped nuclei localized in lateral positions of the hypha all along the germ-tube length. Beside these, round-shaped nuclei were found to migrate along the central germ-tube core. Some (rare) germ-tube areas, delimited by septa and containing irregularly shaped, much brighter fluorescent nuclei were also found. Specimens that had just initiated the septation process after germ-tube growth arrest displayed round or oval-shaped nuclei in several portions of the germ tubes. These hyphal areas often alternated with other septa-delimited cytoplasmic clusters which contained distorted, brightly fluorescent nuclei. Completely septated specimens mostly lacked nuclei along their germ tubes. However, highly fluorescent chromatin masses appeared within remnants of cytoplasmic material, often compressed between close septa. Our results provide a first clear picture of the in vivo distribution of nuclei along arbuscular mycorrhizal fungal germ tubes issued from resting spores, and suggest that selective areas of their coenocytic hyphae are under specific, single nuclear control. They indicate as well that random autolytic processes occur along senescing G. rosea germ tubes, probably as a consequence of the absence of a host root signal for mycorrhizal formation. Finally, the data presented here allow us to envisage the fate of nuclei released by the germinating spore after nonsymbiotic fungal growth arrest.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

Abbreviations

AM:

fungi arbuscular-mycorrhizal fungi

DAPI:

4′, 6-diamidino-2-phenylindole

FM:

fluorescence microscopy

CLSM:

confocal laser scanning microscopy

2PM:

two-photon microscopy

PI:

propidium iodide

PMT:

photomultiplier tube

References

  • Alberts B, Bray D, Lewis J, Raff M, Roberts K, Watson JD (1994) Molecular biology of the cell, 3rd edn. Garland Publishing, New York

    Google Scholar 

  • Arndt-Jovin DJ, Jovin TM (1989) Fluorescence labeling and microscopy of DNA. Methods Cell Biol 30: 417–448

    CAS  PubMed  Google Scholar 

  • Åström H, Giovannetti M, Raudaskoski M (1994) Cytoskeletal components in the arbuscular mycorrhizal fungus Glomus mosseae. Mol Plant Microbe Interact 7: 309–312

    Google Scholar 

  • Azcón-Aguilar C, Bago B (1994) Physiological characteristics of the host plant promoting an undisturbed functioning of the mycorrhizal 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 (1995) Saprophitic growth of AMF. In: Varma A, Hock B (eds) Mycorrhiza: structure, function, molecular biology, and biotechnology. Springer, Berlin Heidelberg New York Tokyo, pp 391–407

    Google Scholar 

  • Bago B (1990) Efecto de distintos compuestos azufrados sobre el crecimiento independiente del hongo formador de micorrizas va Glomus mosseae. Master thesis, Universidad de Granada, Granada, Spain

    Google Scholar 

  • —, Vierheilig H, Piché Y, Azcón-Aguilar C (1996) Nitrate depletion and pH changes induced by the extraradical mycelium of the arbuscular mycorrhizal fungus Glomus intraradices grown in monoxenic culture. New Phytol 133: 273–280

    CAS  PubMed  Google Scholar 

  • Bago B, Bentivenga SP, Brenac V, Dodd JC, Piché Y, Simon L (1998) Molecular analysis of Gigaspora (Glomales, Giga-sporaceae). New Phytol 139 (in press)

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

    Google Scholar 

  • Barea JM, Jeffries P (1995) Arbuscular mycorrhizas in sustainable soil plant systems. In: Varma A, Hock B (eds) Mycorrhiza: structure, function, molecular biology, and biotechnology. Springer, Berlin Heidelberg New York Tokyo, pp 521–560

    Google Scholar 

  • Bécard G, Pfeffer PE (1993) Status of nuclear division in arbuscular mycorrhizal fungi during in vitro development. Protoplasma 174: 62–68

    Google Scholar 

  • —, Piché Y (1989) Fungal growth stimulation by CO2 and root exudates in vesicular-arbuscular mycorrhizal symbiosis. Appl Environ Microbiol 55: 2320–2325

    PubMed  PubMed Central  Google Scholar 

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

    Google Scholar 

  • — — (1993) Evidence of DNA replication in an arbuscular mycorrhizal fungus in the absence of the host plant. Protoplasma 176: 100–105

    CAS  Google Scholar 

  • Bonfante P, Bianciotto V (1995) Presymbiotic versus symbiotic phase in arbuscular endomycorrhizal fungi: morphology and cytology. In: Varma A, Hock B (eds) Mycorrhiza: structure, function, molecular biology, and biotechnology. Springer, Berlin Heidelberg New York Tokyo, pp 229–247

    Google Scholar 

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

    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

    Google Scholar 

  • Burggraaf AJP, Beringer JE (1989) Absence of nuclear DNA synthesis in vesicular-arbuscular mycorrhizal fungi during in vitro development. New Phytol 111: 25–33

    Google Scholar 

  • Butt TM, Hoch HC, Staples RC, St Leger RJ (1989) Use of fluorochromes in the study of fungal cytology and differentiation. Exp Mycol 13: 303–320

    CAS  Google Scholar 

  • Coleman AW, Goff LJ (1980) Applications of fluorochromes to pollen biology I: mithramycin and 4′,6-diamidino-2-phenylindole (DAPI) as vital stains and for quantitation of nuclear DNA. Stain Technol 60: 145–154

    Google Scholar 

  • —, Maguire MJ, Coleman JR (1981) Mithramycin and 4′, 6-diamidino-2-phenylindole (DAPI): DNA staining for fluorescence microspectrophotometric measurements in nuclei, plastids and virus particles. J Histochem 29: 959–968

    CAS  Google Scholar 

  • Cooke JC, Gemma JN, Koske RE (1987) Observations of nuclei in vesicular-arbuscular mycorrhizal fungi. Mycologia 79: 331–333

    Google Scholar 

  • Czymmek KJ, Whallon JH, Klomparens KL (1994) Confocal microscopy in mycological research. Exp Mycol 18: 275–293

    Google Scholar 

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

    CAS  PubMed  Google Scholar 

  • —, 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 

  • Ellis R, Yuan J, Horvitz R (1991) Mechanisms and functions of cell death. Annu Rev Cell Biol 7: 663–698

    CAS  PubMed  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) Relation of a large soil-borne spore to phycomycetous mycorrhizal infections. Mycologia 47: 619

    Google Scholar 

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

    Google Scholar 

  • Giovannetti M, Sbrana C, Avio L, Citernesi AS, Logi C (1994) Recognition and infection process, basis for host specificity of arbuscular mycorrhizal fungi. In: Gianinazzi S, Schüepp H (eds) Impact of arbuscular mycorrhizas on sustainable agriculture and natural ecosystems. Birkhäuser, Basel, pp 61–72

    Google Scholar 

  • Groover A, De Witt N, Heidel A, Jones A (1997) Programmed cell death of plant tracheary elements differentiating in vitro. Protoplasma 196: 197–211

    Google Scholar 

  • Heath IB (1987) Fluorescent staining of fungal nuclei. In: Fuller MS, Jaworski A (eds) Zoosporic fungi in teaching and research. Southeastern Publishing, Greenville, pp 169–171

    Google Scholar 

  • — (1994) The cytoskeleton in hyphal growth, organelle movements and mitosis. In: Wessels JGH, Meinhardt F (eds) The Mycota, vol 1, growth, differentiation and sexuality. Springer, Berlin Heidelberg New York Tokyo, pp 43–65

    Google Scholar 

  • Hepper C (1983) Limited independent growth of a vesicular-arbuscular mycorrhizal fungus in vitro. New Phytol 93: 537–542

    Google Scholar 

  • — (1984) Isolation and culture of VA mycorrhizal (VAM) fungi. In: Powell CL, Bagyaraj DJ (eds) VA mycorrhiza. CRC Press, Boca Raton, pp 95–112

    Google Scholar 

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

    Google Scholar 

  • Jacobson DJ, Beurkens K, Klomparens KL (1998) Microscopic and ultrastructural examination of vegetative incompatibility in partial diploids heterozygous at het loci in Neurospora crassa. Fungal Gen Biol 23: 45–56

    CAS  Google Scholar 

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

    CAS  PubMed  Google Scholar 

  • Katsuhara M, Kawasaki T (1996) Salt stress induced nuclear and DNA degradation in meristematic cells of barley roots. Plant Cell Physiol 37: 169–173

    CAS  Google Scholar 

  • Kosslak RM, Chamberlin MA, Palmer RG, Bowen BA (1997) Programmed cell death in the root cortex of soybean root necrosis mutants. Plant J 11: 729–745

    CAS  PubMed  Google Scholar 

  • Legrand EK (1997) An adaptationist view of apoptosis. Q Rev Biol 72: 135–147

    CAS  PubMed  Google Scholar 

  • Marsh BAB (1971) Measurement of length in random arrangement of lines. J Appl Ecol 8: 265–267

    Google Scholar 

  • Martin SJ, Green DR, Cotter TG (1994) Dicing with death: dissecting the components of the apoptosis machinery. Trends Biochem Sci 19: 26–30

    CAS  PubMed  Google Scholar 

  • Meier R, Charvat I (1992) Germination of Glomus mosseae spores: procedure and ultrastructural analysis. Int J Plant Sci 153: 541–549

    Google Scholar 

  • Miller T, Beausang LA, Meneghini M, Lidgard G (1997) Death-induced changes to the nuclear matrix: the use of anti-nuclear matrix antibodies to study agents of apoptosis. BioTechniques 15: 1042–1047

    Google Scholar 

  • Mosse B (1996) The regular germination of resting spores and some observations on the growth requirements of an Endogone sp. causing vesicular-arbuscular mycorrhizas. Trans Br Mycol Soc 42: 273–286

    Google Scholar 

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

    CAS  PubMed  Google Scholar 

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

    Google Scholar 

  • Nooden LD, Guiamet JJ, John I (1997) Senescence mechanisms. Physiol Plant 101: 746–753

    CAS  Google Scholar 

  • Pawley JB (ed) (1995) Handbook of biological confocal microscopy. Plenum, New York

    Google Scholar 

  • Sanders IR, Wiemken A (1997) The diversity of AM fungi and its ecological significance. In: 48th Annual Meeting of the American Institute of Biological Sciences, August 3–7, 1997, Palais des Congrès de Montréal, Montréal, Canada, p 120

    Google Scholar 

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

    Google Scholar 

  • Sward RJ (1981a) The structure of the spores of Gigaspora margarita I: the dormant spore. New Phytol 87: 761–768

    Google Scholar 

  • — (1981b) The structure of the spores of Gigaspora margarita II: changes accompanying germination. New Phytol 88: 661–666

    Google Scholar 

  • — (1981c) The structure of the spores of Gigaspora margarita III: germ-tube emergence and growth. New Phytol 88: 667–673

    Google Scholar 

  • Toda T, Yamamoto M, Yanagida M (1981) Sequential alterations in the nuclear chromatin region during mitosis of the fission yeast Schizosaccharomyces pombe: video fluorescence microscopy of synchronous growing wild-type and cold-sensitive cdc mutants by using a DNA-binding fluorescent probe. J Cell Sci 52: 271–287

    CAS  PubMed  Google Scholar 

  • Trinci APJ, Righelato RC (1970) Changes in constituents and ultrastructure of hyphal compartments during autolysis of glucosa starved Penicillum chysogenum. J Gen Microbiol 60: 239–249

    CAS  PubMed  Google Scholar 

  • Umar MH, Vangriensven LJLD (1997) Morphogenetic cell death in developing primordia of Agaricus bisporus. Mycologia 89: 274–277

    Google Scholar 

  • Viera A, Glenn MG (1990) DNA content of vesicular-arbuscular mycorrhizal fungal spores. Mycologia 82: 263–267

    CAS  Google Scholar 

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

    Google Scholar 

  • Watrud LS, Heithaus III JJ, Jaworski A (1978) Geotropism in the endomycorrhizal fungus Gigaspora margarita. Mycologia 70: 449–452

    Google Scholar 

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

    CAS  PubMed  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

    CAS  Google Scholar 

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

    CAS  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Bago, B., Zipfel, W., Williams, R.M. et al. In vivo studies on the nuclear behavior of the arbuscular mycorrhizal fungus Gigaspora rosea grown under axenic conditions. Protoplasma 203, 1–15 (1998). https://doi.org/10.1007/BF01280582

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01280582

Keywords

Navigation