Skip to main content

Pseudohyphal growth of Cryptococcus neoformans is a reversible dimorphic transition in response to ammonium that requires Amt1 and Amt2 ammonium permeases.

Publication ,  Journal Article
Lee, SC; Phadke, S; Sun, S; Heitman, J
Published in: Eukaryot Cell
November 2012

Cryptococcus neoformans is a human-pathogenic basidiomycete that commonly infects HIV/AIDS patients to cause meningoencephalitis (7, 19). C. neoformans grows as a budding yeast during vegetative growth or as hyphae during sexual reproduction. Pseudohyphal growth of C. neoformans has been observed rarely during murine and human infections but frequently during coculture with amoeba; however, the genetics underlying pseudohyphal growth are largely unknown. Our studies found that C. neoformans displays pseudohyphal growth under nitrogen-limiting conditions, especially when a small amount of ammonium is available as a sole nitrogen source. Pseudohyphal growth was observed with Cryptococcus neoformans serotypes A and D and Cryptococcus gattii. C. neoformans pseudohyphae bud to produce yeast cells and normal smooth hemispherical colonies when transferred to complete media, indicating that pseudohyphal growth is a conditional developmental stage. Subsequent analysis revealed that two ammonium permeases encoded by the AMT1 and AMT2 genes are required for pseudohyphal growth. Both amt1 and amt2 mutants are capable of forming pseudohyphae; however, amt1 amt2 double mutants do not form pseudohyphae. Interestingly, C. gattii pseudohypha formation is irreversible and involves a RAM pathway mutation that drives pseudohyphal development. We also found that pseudohyphal growth is related to the invasive growth into the medium. These results demonstrate that pseudohyphal growth is a common reversible growth pattern in C. neoformans but a mutational genetic event in C. gattii and provide new insights into understanding pseudohyphal growth of Cryptococcus.

Duke Scholars

Published In

Eukaryot Cell

DOI

EISSN

1535-9786

Publication Date

November 2012

Volume

11

Issue

11

Start / End Page

1391 / 1398

Location

United States

Related Subject Headings

  • Spores, Fungal
  • Species Specificity
  • Quaternary Ammonium Compounds
  • Nitrogen
  • Mutation
  • Microdissection
  • Microbiology
  • Hyphae
  • Genes, Fungal
  • Fungal Proteins
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Lee, S. C., Phadke, S., Sun, S., & Heitman, J. (2012). Pseudohyphal growth of Cryptococcus neoformans is a reversible dimorphic transition in response to ammonium that requires Amt1 and Amt2 ammonium permeases. Eukaryot Cell, 11(11), 1391–1398. https://doi.org/10.1128/EC.00242-12
Lee, Soo Chan, Sujal Phadke, Sheng Sun, and Joseph Heitman. “Pseudohyphal growth of Cryptococcus neoformans is a reversible dimorphic transition in response to ammonium that requires Amt1 and Amt2 ammonium permeases.Eukaryot Cell 11, no. 11 (November 2012): 1391–98. https://doi.org/10.1128/EC.00242-12.
Lee, Soo Chan, et al. “Pseudohyphal growth of Cryptococcus neoformans is a reversible dimorphic transition in response to ammonium that requires Amt1 and Amt2 ammonium permeases.Eukaryot Cell, vol. 11, no. 11, Nov. 2012, pp. 1391–98. Pubmed, doi:10.1128/EC.00242-12.

Published In

Eukaryot Cell

DOI

EISSN

1535-9786

Publication Date

November 2012

Volume

11

Issue

11

Start / End Page

1391 / 1398

Location

United States

Related Subject Headings

  • Spores, Fungal
  • Species Specificity
  • Quaternary Ammonium Compounds
  • Nitrogen
  • Mutation
  • Microdissection
  • Microbiology
  • Hyphae
  • Genes, Fungal
  • Fungal Proteins