Cytoplasmic contractions in growing fungal hyphae and their morphogenetic consequences


Video-enhanced light microscopy of the apical and subapical regions of growing hyphae of several fungal species revealed the existence of momentary synchronized motions of subcellular organelles. First discovered in a temperature-sensitive morphological mutant (ramosa-1) of Aspergillus niger, these seemingly spontaneous cytoplasmic contractions were also detected in wild-type hyphae of A. niger, Neurospora crassa, and Trichoderma atroviride. Cytoplasmic contractions in all fungi lasted about 1 s. Although the cytoplasm recovered its motility and appearance, the contraction usually led to drastic changes in Spitzenkörper (apical body) behavior and hyphal morphology, often both. Within 10 s after the contraction, the Spitzenkörper commonly became dislodged from its polar position; sometimes it disassembled into phase-dark and phase-light components; more commonly, it disappeared completely. Whether partial or complete, the dislocation of the Spitzenkörper was always accompanied by a sharp reduction or cessation of growth, and was usually followed by marked morphological changes that included bulbous hyphal tips, bulges in the hyphal profile, and formation of subapical and apical branches. The cytoplasmic contractions are vivid evidence that the most conspicuous cell organelles (membrane-bound) in living hyphae are interconnected via a contractile cytoskeletal network.

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

Access options

Buy single article

Instant unlimited access to the full article PDF.

US$ 39.95

Price includes VAT for USA

Subscribe to journal

Immediate online access to all issues from 2019. Subscription will auto renew annually.

US$ 199

This is the net price. Taxes to be calculated in checkout.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6.
Fig. 7.


  1. 1.

    A hypha can be divided into three regions according to the hyphal equation (Diéguez-Uribeondo et al. 2004): the apex, which extends from the apical pole to 2d (d = the distance between the VSC or Spitzenkörper and the apical pole), the subapex, extending from 2d to 20d, and the mature region, beyond 20d.


  1. Bartnicki DD (1994) The design and implementation of computer simulation for fungal morphogenesis. MSc Dissertation, University of California, Riverside

  2. Bartnicki-García S (2002) Hyphal tip growth, outstanding questions. In: Osiewacz HD (ed) Molecular biology of fungal development. Marcel Dekker, New York, pp29–58

  3. Bartnicki-García S, Hergert F, Gierz G (1989) Computer simulation of fungal morphogenesis and the mathematical basis for hyphal (tip) growth. Protoplasma 153:46–57

  4. Bourett TM, Howard RJ (1991) Ultrastructural immunolocalization of actin in a fungus. Protoplasma 163:199–202

  5. Diéguez-Uribeondo J, Gierz G, Bartnicki-García S (2004) Image analysis of hyphal morphogenesis in Saprolegniaceae (oomycetes). Fungal Genet Biol 41:293–307

  6. Girbardt M (1957) Der Spitzenkörper von Polystictus versicolor (L.). Planta 50:47–59

  7. Harold FM (1997) How hyphae grow: morphogenesis explained? Protoplasma 197:137–147

  8. Heath IB (1994) The cytoskeleton in hyphal growth, organelle movements, and mitosis In: Wessels JGH, Meinhardt M (eds) The mycota I, growth, differentiation and sexuality. Springer, Berlin Heidelberg New York, pp 43–65

  9. Ingber DE (2003) Tensegrity I Cell structure and hierarchical systems biology. J Cell Sci 116:1157–1173

  10. Jackson SL, Heath IB (1992) UV microirradiations elicit Ca+ dependent apex-directed cytoplasmic contractions in hyphae. Protoplasma 170:46–52

  11. López-Franco R (1992) Organization and dynamics of the Spitzenkörper in growing hyphal tips. PhD Dissertation, Purdue University, West Lafayette

  12. López-Franco R, Bracker CE (1996) Diversity and dynamics of the Spitzenkörper in growing hyphal tips of higher fungi. Protoplasma 195:90–111

  13. MackIntosh ME, Pritchard H (1963) The production and replica plating of micro-colonies of Aspergillus nidulans. Genet Res Camb 4:320–322

  14. Mason D, Powelson DM (1956) Nuclear division as observed in live bacteria by a new technique. J Bacteriol 71:474–481

  15. McDaniel DP, Roberson R (2000) Microtubules are required for motility and positioning of vesicles and mitochondria in hyphal tip cells of Allomyces macrogynus. Fungal Genet Biol 31:233–244

  16. McKerracher LJ, Heath IB (1986a) Fungal nuclear behavior analyzed by ultraviolet microbeam irradiation. Cell Motil Cytoskel 6:35–47

  17. McKerracher LJ, Heath IB (1986b) Polarized cytoplasmic movement and inhibition of saltations induced by calcium-mediated effects of microbeams in fungal hyphae. Cell Motil Cytoskel 6:136–145

  18. Perkins DD (1962) Preservation of Neurospora stock cultures with anhydrous silica gel. Can J Microbiol 8:591–594

  19. Reynaga-Peña CG, Bartnicki-García S (1997) Apical branching in a temperature sensitive mutant of Aspergillus niger. Fungal Genet Biol 22:153–167

  20. Riquelme M, Reynaga-Peña CG, Gierz G, Bartnicki-García S (1998) What determines growth direction in fungal hyphae? Fungal Genet Biol 24:101–109

  21. Vargas MM, Aronson JM, Roberson RW (1993) The cytoplasmic organization of hyphal tip cells in the fungus Allomyces macrogynus. Protoplasma 176:43–52

  22. Vogel HJ (1956) A convenient growth medium for Neurospora (medium N). Microbial Gen Bull 13:42–43

Download references


We thank Robert W. Roberson and Meritxell Riquelme for valuable advice and Ricardo Mendoza for his help with digitalization of video sequences. The experimental portion of this work was supported in part by grants from the National Institutes of Health (GM-48257), the National Science Foundation (IBN-9204541), a special grant from Consejo Nacional de Ciencia y Tecnología, Mexico (DG/2003-1158), and fellowships from SNI (Sistema Nacional de Investigadores, México).

Author information

Correspondence to Salomón Bartnicki-García.

Electronic Supplementary Material

(MPEG 740 KB)

(AVI 1.4 MB)

(AVI 3.1 MB)

(MPEG 740 KB)

(AVI 1.4 MB)

(AVI 3.1 MB)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Reynaga-Peña, C.G., Bartnicki-García, S. Cytoplasmic contractions in growing fungal hyphae and their morphogenetic consequences. Arch Microbiol 183, 292–300 (2005).

Download citation


  • Cytoplasmic contractions
  • Fungal growth
  • Spitzenkörper
  • Organelle movement
  • Ramosa-1
  • Aspergillus niger
  • Neurospora crassa
  • Trichoderma atroviride