Centromere Structure and Function in Candida albicans

Summary

Principal Investigator: Judith G Berman
Affiliation: University of Minnesota
Country: USA
Abstract: Candida albicans is an important human fungal pathogen that causes superficial mucosal and lethal systemic infections. Prophylactic antifungal treatments often result in the appearance of acquired drug resistance. C. albicans does not undergo meiosis;genetic diversity arises through somatic mitotic events such as chromosome non-disjunction. We recently found that acquired resistance to fluconazole is often conferred by genome rearrangements involving the centromere of chromosome 5. Centromeres (CENs) are the DNA regions where proteins assemble to form kinetochores, the structures that tether chromosomes to the mitotic spindle. They are critical to proper chromosome segregation and ultimately to genome stability and cell survival. C. albicans has regional CENs like those of higher organisms including humans, and unlike the well characterized point centromeres of Saccharomyces cerevisiae. Importantly, C. albicans CENs are much smaller and simpler than the smallest characterized regional CENs, thus providing a unique opportunity to use C. albicans as a model for the study of regional CENs. Our preliminary results show that deletion of a CEN region can be accompanied by formation of a neocentromere, an ectopic centromere that forms at non- centromeric DNA. Furthermore, we have constructed CEN-plasmids that will be useful for many applications. Our long term goals are: a) to understand the DNA and proteins that specify C. albicans centromere function;b) to design useful molecular tools that exploit our understanding of centromere function and facilitate the study of basic and applied processes in C. albicans. Specifically, we will develop strains that use ADE2-marked CEN-plasmids in a powerful screen for compounds with potential therapeutic value. Our work is critical for the development of two types of potential therapies directed at centromeres: drugs that kill fungi by directly targeting essential fungal centromere components that differ from those in the human centromere;and companion therapies that eliminate aneuploidies and therefore could be administered together with currently available antifungals in order to extend their usefulness. We propose to: 1) determine the requirements for CEN function within native chromosomes;2) determine the requirements for the establishment and maintenance of CEN function on CEN-plasmids;and 3) use CEN-plasmids to screen for candidate antifungal drugs and companion drugs that affect chromosome stability and the acquisition of drug resistance and could extend the usefulness of existing antifungal drugs. PUBLIC HEALTH RELEVANCE: Fungal infections are a serious health problem due to the limited number of antifungal drugs available and the rapid acquisition of resistance to antifungals seen in the clinic. In Candida albicans, the most prevalent fungal pathogen of humans, acquired drug resistance arises from defects in chromosome segregation. We will develop tools to study this process and will identify companion drugs that inhibit these defects, thereby extending the usefulness of available antifungal therapies.
Funding Period: 2008-06-01 - 2013-05-31
more information: NIH RePORT

Top Publications

  1. pmc Three-dimensional localization of CENP-A suggests a complex higher order structure of centromeric chromatin
    Owen J Marshall
    Chromosome and Chromatin Research, Murdoch Childrens Research Institute, Royal Children s Hospital, Parkville, Victoria 3052, Australia
    J Cell Biol 183:1193-202. 2008
  2. pmc Shuttle vectors for facile gap repair cloning and integration into a neutral locus in Candida albicans
    Maryam Gerami-Nejad
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
    Microbiology 159:565-79. 2013
  3. pmc The three clades of the telomere-associated TLO gene family of Candida albicans have different splicing, localization, and expression features
    Matthew Z Anderson
    Department of Genetics, Cell Biology and Development, University of Minnesota Twin Cities, Minneapolis, MN, USA
    Eukaryot Cell 11:1268-75. 2012
  4. pmc Analysis of protein function in clinical C. albicans isolates
    Maryam Gerami-Nejad
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
    Yeast 29:303-9. 2012
  5. pmc Neocentromeres and epigenetically inherited features of centromeres
    Laura S Burrack
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
    Chromosome Res 20:607-19. 2012
  6. pmc Monopolin recruits condensin to organize centromere DNA and repetitive DNA sequences
    Laura S Burrack
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455 Department of Molecular Microbiology and Biotechnology, George Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv 69978, Israel
    Mol Biol Cell 24:2807-19. 2013
  7. pmc Evolution of pathogenicity and sexual reproduction in eight Candida genomes
    Geraldine Butler
    UCD School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
    Nature 459:657-62. 2009
  8. pmc Dancing genomes: fungal nuclear positioning
    Amy Gladfelter
    Department of Biological Sciences, Gillman Hall, Dartmouth College, Hanover, New Hampshire 03755, USA
    Nat Rev Microbiol 7:875-86. 2009
  9. pmc Flexibility of centromere and kinetochore structures
    Laura S Burrack
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55405, USA
    Trends Genet 28:204-12. 2012
  10. pmc The requirement for the Dam1 complex is dependent upon the number of kinetochore proteins and microtubules
    Laura S Burrack
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
    Curr Biol 21:889-96. 2011

Detail Information

Publications19

  1. pmc Three-dimensional localization of CENP-A suggests a complex higher order structure of centromeric chromatin
    Owen J Marshall
    Chromosome and Chromatin Research, Murdoch Childrens Research Institute, Royal Children s Hospital, Parkville, Victoria 3052, Australia
    J Cell Biol 183:1193-202. 2008
    ..C., L.H. Wong, N. Wong, and K.H.A. Choo. 2005. Hum. Mol. Genet. 14:85-93), our data suggest that centromeric chromatin is arranged in a coiled 30-nm fiber that is itself coiled or folded to form a higher order structure...
  2. pmc Shuttle vectors for facile gap repair cloning and integration into a neutral locus in Candida albicans
    Maryam Gerami-Nejad
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
    Microbiology 159:565-79. 2013
    ..albicans...
  3. pmc The three clades of the telomere-associated TLO gene family of Candida albicans have different splicing, localization, and expression features
    Matthew Z Anderson
    Department of Genetics, Cell Biology and Development, University of Minnesota Twin Cities, Minneapolis, MN, USA
    Eukaryot Cell 11:1268-75. 2012
    ..albicans with the ability to adapt rapidly to the broad range of different environmental niches within the human host...
  4. pmc Analysis of protein function in clinical C. albicans isolates
    Maryam Gerami-Nejad
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
    Yeast 29:303-9. 2012
    ..Together, these vectors provide a useful set of genetic tools for studying diverse aspects of gene function in both clinical and laboratory strains of C. albicans...
  5. pmc Neocentromeres and epigenetically inherited features of centromeres
    Laura S Burrack
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
    Chromosome Res 20:607-19. 2012
    ....
  6. pmc Monopolin recruits condensin to organize centromere DNA and repetitive DNA sequences
    Laura S Burrack
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455 Department of Molecular Microbiology and Biotechnology, George Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv 69978, Israel
    Mol Biol Cell 24:2807-19. 2013
    ..We propose that the key function of monopolin is to recruit condensin in order to promote the assembly of higher-order structure at centromere and repetitive DNA. ..
  7. pmc Evolution of pathogenicity and sexual reproduction in eight Candida genomes
    Geraldine Butler
    UCD School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
    Nature 459:657-62. 2009
    ..Analysis of the CUG leucine-to-serine genetic-code change reveals that 99% of ancestral CUG codons were erased and new ones arose elsewhere. Lastly, we revise the Candida albicans gene catalogue, identifying many new genes...
  8. pmc Dancing genomes: fungal nuclear positioning
    Amy Gladfelter
    Department of Biological Sciences, Gillman Hall, Dartmouth College, Hanover, New Hampshire 03755, USA
    Nat Rev Microbiol 7:875-86. 2009
    ....
  9. pmc Flexibility of centromere and kinetochore structures
    Laura S Burrack
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55405, USA
    Trends Genet 28:204-12. 2012
    ..In this review, we explore the mechanisms and consequences of centromere and kinetochore flexibility as well as the benefits and limitations of different experimental model systems for their study...
  10. pmc The requirement for the Dam1 complex is dependent upon the number of kinetochore proteins and microtubules
    Laura S Burrack
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
    Curr Biol 21:889-96. 2011
    ..Rather, the Dam1 complex is less critical when chromosomes have multiple kinetochore complexes and microtubules per centromere, implying that it functions as a processivity factor in vivo as well as in vitro...
  11. pmc CaMtw1, a member of the evolutionarily conserved Mis12 kinetochore protein family, is required for efficient inner kinetochore assembly in the pathogenic yeast Candida albicans
    Babhrubahan Roy
    Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, India
    Mol Microbiol 80:14-32. 2011
    ..We propose that Mis12/Mtw1 proteins also have important co-dependent interactions with inner kinetochore proteins and that these interactions may increase the fidelity of kinetochore formation...
  12. pmc Epigenetically-inherited centromere and neocentromere DNA replicates earliest in S-phase
    Amnon Koren
    Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minnesota, USA
    PLoS Genet 6:e1001068. 2010
    ..We suggest a model in which the distinct timing of DNA replication serves as an epigenetic mechanism for the inheritance of centromere position...
  13. pmc The transcription factor homolog CTF1 regulates {beta}-oxidation in Candida albicans
    Melissa A Ramirez
    Department of Microbiology and Molecular Genetics, The University of Texas Health Science Center, 6431 Fannin, Houston, TX 77030, USA
    Eukaryot Cell 8:1604-14. 2009
    ..Thus, phenotypic and genotypic observations highlight important differences in the regulatory network for alternative carbon metabolism in C. albicans compared to the paradigms developed in other model fungi...
  14. pmc Additional cassettes for epitope and fluorescent fusion proteins in Candida albicans
    Maryam Gerami-Nejad
    Department of Genetics, Cell Biology and Development, University of Minnesota, MN 55455, USA
    Yeast 26:399-406. 2009
    ..These reagents expand the repertoire of molecular tools available for working with C. albicans and other members of the CUG clade of pathogenic yeasts...
  15. pmc Neocentromeres form efficiently at multiple possible loci in Candida albicans
    Carrie Ketel
    Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minnesota, United States of America
    PLoS Genet 5:e1000400. 2009
    ..The ability to select for neocentromere formation and movement in C. albicans permits mechanistic analysis of the assembly and maintenance of a regional centromere...
  16. pmc Acquisition of aneuploidy provides increased fitness during the evolution of antifungal drug resistance
    Anna M Selmecki
    Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota, USA
    PLoS Genet 5:e1000705. 2009
    ..The early appearance of aneuploidy is consistent with a model in which C. albicans becomes more permissive of chromosome rearrangements and segregation defects in the presence of fluconazole...