Chapter 4 : Hypha Formation and Virulence

MyBook is a cheap paperback edition of the original book and will be sold at uniform, low price.

Preview this chapter:
Zoom in

Hypha Formation and Virulence, Page 1 of 2

| /docserver/preview/fulltext/10.1128/9781555815776/9781555813680_Chap04-1.gif /docserver/preview/fulltext/10.1128/9781555815776/9781555813680_Chap04-2.gif


Current research shows that major changes in gene expression accompany morphogenesis and suggest that fungal attributes necessary for proliferation and survival in the host are present in both yeast and hyphal growth forms. Manipulation of host-fungus interactions in animal models has provided insight into the role of hypha formation in virulence. The use of genetic manipulation has led to the discovery that transcription factors and signal transduction pathways are critical for the proper regulation of morphogenic conversions in . Mutant strains of that are defective in hypha production in host tissue have reduced virulence in murine models of systemic candidiasis. A caveat associated with the use of morphogenic mutants in attempts to understand the role of hypha formation in virulence is that the roles of apical and budding modes of growth cannot be separated from morphology-specific gene expression. Studies of mutants displaying defects in hypha-specific gene expression but not in hypha production support the principle that the role of hyphae in virulence is more closely related to the changes in gene expression profiles that accompany hyphal growth than to hyphal growth itself. In addition to HWP1, PLD1, and other potential virulence factors, genes that could potentially regulate virulence factor gene expression during hypha production, such as those encoding transcription factors, signal transduction components, and proteins that function in secretion, as well as others, were identified.

Citation: Sundstrom P. 2006. Hypha Formation and Virulence, p 45-47. In Heitman J, Filler S, Edwards, Jr. J, Mitchell A (ed), Molecular Principles of Fungal Pathogenesis. ASM Press, Washington, DC. doi: 10.1128/9781555815776.ch4
Highlighted Text: Show | Hide
Loading full text...

Full text loading...


1. Bahn, Y. S.,, J. Staab, and, P. Sundstrom. 2003. Increased high-affinity phosphodiesterase PDE2 gene expression in germ tubes counteracts CAP1-dependent synthesis of cyclic AMP, limits hypha production and promotes virulence of Candida albicans. Mol. Microbiol. 50: 391409.
2. Bahn, Y. S., and, P. Sundstrom. 2001. CAP1 , an adenylate cyclase-associated protein gene, regulates bud-hypha transitions, filamentous growth, and cyclic AMP levels and is required for virulence of Candida albicans. J. Bacteriol. 183: 32113223.
3. Braun, B. R., and, A. D. Johnson. 1997. Control of filament formation in Candida albicans by the transcriptional repressor TUP1. Science 277: 105109.
4. Braun, B. R.,, D. Kadosh, and, A. D. Johnson. 2001. NRG1, a repressor of filamentous growth in C. albicans, is down-regulated during filament induction. EMBO J. 20: 47534761.
5. Deacon, J. 1997. Modern Mycology, 3rd ed. Blackwell Science, Oxford, United Kingdom.
6. Dolan, J. W.,, A. C. Bell,, B. Hube,, M. Schaller,, T. F. Warner, and, E. Balish. 2004. Candida albicans PLD I activity is required for full virulence. Med. Mycol. 42: 439447.
7. Elahi, S.,, G. Pang,, R. Clancy, and, R. B. Ashman. 2000. Cellular and cytokine correlates of mucosal protection in murine model of oral candidiasis. Infect. Immun. 68: 57715777.
8. Gow, N. A.,, A. J. Brown, and, F. C. Odds. 2002. Fungal morphogenesis and host invasion. Curr. Opin. Microbiol. 5: 366371.
9. Hornby, J. M.,, R. Dumitru, and, K. W. Nickerson. 2004. High phosphate (up to 600 mM) induces pseudohyphal development in five wild type Candida albicans. J. Microbiol. Methods 56: 119124.
10. Hube, B. 2004. From commensal to pathogen: stage- and tissue-specific gene expression of Candida albicans. Curr. Opin. Microbiol. 7: 336341.
11. Lo, H. J.,, J. R. Kohler,, B. DiDomenico,, D. Loebenberg,, A. Cacciapuoti, and, G. R. Fink. 1997. Nonfilamentous C. albicans mutants are avirulent. Cell 90: 939949.
12. Murad, A. M.,, C. d’Enfert,, C. Gaillardin,, H. Tournu,, F. Tekaia,, D. Talibi,, D. Marechal,, V. Marchais,, J. Cottin, and, A. J. Brown. 2001. Transcript profiling in Candida albi-cans reveals new cellular functions for the transcriptional repressors CaTup1, CaMig1 and CaNrg1. Mol. Microbiol. 42: 981993.
13. Nantel, A.,, D. Dignard,, C. Bachewich,, D. Harcus,, A. Marcil,, A. P. Bouin,, C. W. Sensen,, H. Hogues,, M. van het Hoog,, P. Gordon,, T. Rigby,, F. Benoit,, D. C. Tessier,, D. Y. Thomas, and, M. Whiteway. 2002. Transcription profiling of Candida albicans cells undergoing the yeast-to-hyphal transition. Mol. Biol. Cell 13: 34523465.
14. Riggle, P. J.,, K. A. Andrutis,, X. Chen,, S. R. Tzipori, and, C. A. Kumamoto. 1999. Invasive lesions containing filamentous forms produced by a Candida albicans mutant that is defective in filamentous growth in culture. Infect. Immun. 67: 36493652.
15. Saville, S. P.,, A. L. Lazzell,, C. Monteagudo, and, J. L. Lopez-Ribot. 2003. Engineered control of cell morphology in vivo reveals distinct roles for yeast and filamentous forms of Candida albicans during infection. Eukaryot. Cell 2: 10531060.
16. Sobel, J. D.,, G. Muller, and, H. R. Buckley. 1984. Critical role of germ tube formation in the pathogenesis of candidal vaginitis. Infect. Immun. 44: 576580.
17. Staab, J. F.,, S. D. Bradway,, P. L. Fidel, and, P. Sundstrom. 1999. Adhesive and mammalian transglutaminase substrate properties of Candida albicans Hwp1. Science 283: 15351538.
18. Sundstrom, P.,, E. Balish, and, C. M. Allen. 2002. Essential role of the Candida albicans transglutaminase substrate, hyphal wall protein 1, in lethal oroesophageal candidiasis in immunodeficient mice. J. Infect. Dis. 185: 521530.
19. Sundstrom, P.,, J. E. Cutler, and, J. F. Staab. 2002. Reevaluation of the role of HWP1 in systemic candidiasis by use of Candida albicans strains with selectable marker URA3 targeted to the ENO1 locus. Infect. Immun. 70: 32813283.

This is a required field
Please enter a valid email address
Please check the format of the address you have entered.
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error