Our research focus is on the evolution of genes and genomes in the major human fungal pathogen Candida albicans and how these genetic changes contribute to phenotypic diversity. C. albicans resides as a harmless commensal in the majority of people worldwide but is capable of causing superficial mucosal infections in otherwise healthy individuals as well as life-threatening systemic infections in patients with compromised immune systems.
Genetic basis of phenotypic diversity
Widespread phenotypic diversity is found among C. albicans clinical isolates, including variability in the extent of disease produced in insect and animal models of infection. This variation is produced by massive genetic diversity between C. albicans strains, which is similar in magnitude to the nucleotide divergence between humans and chimpanzees. We are working to identify the genetic basis for C. albicans phenotypic diversity and explore how individual polymorphisms affect host/pathogen interactions using combined quantitative genetic approaches. Differential host response to C. albicans isolates remains an underexplored topic and our research will provide insight into how natural selection acts upon this variation in the context of commensalism and infection.
Expanded gene families in virulence
The telomere-associated (TLO) gene family has expanded significantly in C. albicans relative to less pathogenic Candida species. These genes encode components of the Mediator complex, a key transcriptional regulator complex in eukaryotes. Significant strain-to-strain variation in gene copy number exists for TLOs although the role of individual paralogs is unclear. We are investigating the molecular and biological roles of individual TLO genes to understand what selective pressures exist to promote gene family expansion and evolution.
- Anderson, M.Z., Wang, J.A., and Bennett, R.J. Rapid evolutionary dynamics masks ancient parasexual mating of Candida albicans. (in preparation)
- Anderson, M.Z., Saha, A., Haseeb, A., and Bennett, R.J. Fluconazole resistance in a Candida albicans isolate is conferred by a novel aneuploidy. (submitted)
- Anderson, M.Z., Porman, A.P., Wang, N., Huang, D., Cuomo, C., and Bennett, R.J. A multistate toggle switch defines fungal cell fates and is regulated by synergistic genetic cues. (in review)
- Anderson, M.Z. and Bennett, R.J. 2016. Budding off: Bringing functional genomics to Candida albicans. Briefings in Functional Genomics. 15: 85-94.
- Anderson, M.Z., Wigen, L., Burrack, L.S., and Berman, J. 2015. Real-time gene movement propels subtelomeric evolution in Candida albicans. Genetics. 200: 907-19.
- Hirakawa, M.P., Martinez, D.A.*, Sakthikumar, S.*, Anderson, M.Z., Berlin, A., Gujja, S., Zeng, Q., Zisson, E., Wang, J.A., Greenberg, J.A., Berman, J., Bennett, R.J., and Cuomo, C.A. 2015. Intra-species variation in Candida albicans: Aneuploidy, loss of heterozygosity, and balancing commensalism and pathogenesis. Genome Research. 25: 413-25.
- Haran, J., Boyle, H., Hokamp, K., Yeomans, T., Liu, Z., Church, M., Fleming, A., Anderson, M.Z., Berman, J., Myers, L.C., Sullivan, D.J., and Moran G. 2014. Telomeric ORFs (TLOs) in Candida spp. encode Mediator subunits that regulate distinct virulence traits. PLoS Genetics. 10: e1004658.
- Anderson, M.Z., Gerstein, A.C., Wigen, L., Baller, J.A., and Berman, J. 2014. Silencing is noisy: Population and cell level noise in telomere-adjacent genes is dependent on telomere position and Sir2. PLoS Genetics. 10: e1004436.
- Anderson, M.Z., Baller, J.A., Dulmage, K., Wigen, L., and Berman, J. 2012. The three clades of the telomere-associated TLO gene family of Candida albicans have different splicing, localization and expression features. Eukaryot Cell. 11:1268-75.
- Anderson, M.Z., Brewer, J.L., Singh, U., and Boothroyd, J.C. 2009. A Pseudouridine Synthase Homologue Is Central to Cellular Differentiation in Toxoplasma gondii. Eukaryotic Cell. 3:398-409.