, Volume 197, Issue 3–4, pp 137–147 | Cite as

How hyphae grow: Morphogenesis explained?

  • F. M. Harold
New Ideas in Cell Biology


Apical growth of fungal hyphae represents a relatively simple instance of cellular morphogenesis. Thanks to the polarized transport and exocytosis of precursor vesicles, new cell wall and plasma membrane are continuously deposited at the hyphal apex; the question is how the characteristic shape of tube and tapered tip comes about. Recent experiments lend support to a model whose central feature is a mobile vesicle supply center corresponding to the Spitzenkörper (apical body) visible in growing hyphae. Shapes predicted by the model agree remarkably well with those of actual hyphae. Nevertheless, critical examination of the model's premises suggests that it requires extension so as to incorporate both a driving force for expansion and a gradient of cell wall plasticity. I propose that a mobile vesicle supply center may be one, but only one, of a range of physiological devices employed by tip-growing organisms to localize the exocytosis of precursor vesicles. Apical growth should ensue whenever the loci of exocytosis advance vectorially, and nascent cell wall expands in a graded manner.


Hyphae Apical growth Tip growth Spitzenkörper Morphogenesis Exocytosis 



vesicle supply center




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Copyright information

© Springer-Verlag 1997

Authors and Affiliations

  • F. M. Harold
    • 1
  1. 1.Department of Biochemistry and Molecular BiologyColorado State UniversityFort CollinsUSA

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