Mycopathologia

, Volume 173, Issue 2–3, pp 113–119 | Cite as

Hydroxyurea Enhances Post-Fusion Hyphal Extension During Sexual Development in C. neoformans var. grubii

  • M. Naim Zulkifli
  • Jan Naseer Kaur
  • John C. Panepinto
Article
First Online:
Received:
Accepted:

Abstract

Mating and sexual development in C. neoformans var. grubii strains of the H99 background is often less robust than that laboratory generated isogenic C. neoformans var. neoformans strains in the JEC21 background. In Candida albicans and Saccharomyces serevisiae, slowing of DNA synthesis and engagement of the replication stress response, such as that caused by treatment with hydroxyurea (HU), induces filamentation and pseudohyphal growth, respectively. In this study, we investigated the effect of HU treatment on C. neoformans var. grubii morphogenesis. Treatment with HU did not induce filamentation of yeast cells either in liquid culture or on solid YPD or V8 agar. In the presence of the opposite mating partner, we observed early emergence of hyphae in the presence of HU. Semi-quantitative analysis of fusion using marked strains demonstrated that no significant enhancement of fusion in the presence of HU. Transfer of fusion colonies from crosses performed in the absence of HU to V8 + HU revealed enhanced hyphal growth in the presence of HU. Analysis of expression of the target of HU, ribonucleotide reductase, revealed that a phylogenetically divergent catalytic subunit is replication stress responsive in C. neoformans. These results suggest that induction of replication stress promotes post-fusion hyphal growth of C. neoformans var. grubii strains in the H99 background.

Keywords

Mating Replication stress Hydroxyurea Sexual development Ribonucleotide reductase Filamentation 
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Notes

Acknowledgments

This work was supported by NRSA K22 AI070647 to JCP and startup funds from the Department of Microbiology and Immunology, College of Medicine and Center of Excellence in Bioinformatics and Life Sciences, State University of New York at Buffalo.

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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • M. Naim Zulkifli
    • 1
  • Jan Naseer Kaur
    • 1
  • John C. Panepinto
    • 1
  1. 1.Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, School of Medicine and Biomedical SciencesState University of New York at BuffaloBuffaloUSA

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