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Biolistic Transformation of a Fluorescent Tagged Gene into the Opportunistic Fungal Pathogen Cryptococcus neoformans
Published on: March 19, 2015
Comparative hybridization reveals extensive genome variation in the AIDS-associated pathogen Cryptococcus neoformans
Guanggan Hu1, Iris Liu, Anita Sham
1Michael Smith Laboratories, The University of British Columbia, 2185 East Mall, Vancouver, British Columbia V6T 1Z4, Canada . hug@interchange.ubc.ca
Genome Biology
|February 26, 2008
Summary
Cryptococcus neoformans genomes show significant variation, including chromosome changes and preferential gene retention. This variability impacts virulence in this AIDS-associated fungal pathogen.
Area of Science:
- Mycology
- Genomics
- Pathogen Biology
Background:
- Genome variability significantly influences pathogenic microbe virulence.
- Comparative genome hybridization (CGH) is a valuable tool for studying microbial genome diversity.
- Cryptococcus neoformans, an AIDS-associated fungal pathogen, exhibits genetic diversity relevant to its virulence.
Purpose of the Study:
- To investigate genome variability in Cryptococcus neoformans strains.
- To compare genomic differences across mating types, molecular subtypes, and ploidy.
- To identify recombination sites and chromosomal alterations in Cryptococcus neoformans.
Main Methods:
- Comparative genome hybridization (CGH) using tiling arrays.
- Analysis of mating-type regions (MATa and MATalpha).
- Genome-wide comparison of environmental and clinical isolates.
Main Results:
- CGH revealed extensive genome variation across serotypes A, D, and AD.
- Identified recombination sites and segment origins within the JEC21 genome.
- Observed disomy for chromosome 13 in haploid strains and preferential chromosome 1 retention in diploids.
Conclusions:
- Cryptococcus neoformans genomes display substantial variation, from small sequence differences to large chromosomal changes.
- Unexpected chromosomal abnormalities like disomy and preferential chromosome retention were identified.
- Understanding this genomic variability is crucial for Cryptococcus neoformans virulence and pathogenesis research.
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