Comparative hybridization reveals extensive genome variation in the AIDS-associated pathogen Cryptococcus neoformans.

Published

Journal Article

Genome variability can have a profound influence on the virulence of pathogenic microbes. The availability of genome sequences for two strains of the AIDS-associated fungal pathogen Cryptococcus neoformans presented an opportunity to use comparative genome hybridization (CGH) to examine genome variability between strains of different mating type, molecular subtype, and ploidy.Initially, CGH was used to compare the approximately 100 kilobase MATa and MATalpha mating-type regions in serotype A and D strains to establish the relationship between the Log2 ratios of hybridization signals and sequence identity. Subsequently, we compared the genomes of the environmental isolate NIH433 (MATa) and the clinical isolate NIH12 (MATalpha) with a tiling array of the genome of the laboratory strain JEC21 derived from these strains. In this case, CGH identified putative recombination sites and the origins of specific segments of the JEC21 genome. Similarly, CGH analysis revealed marked variability in the genomes of strains representing the VNI, VNII, and VNB molecular subtypes of the A serotype, including disomy for chromosome 13 in two strains. Additionally, CGH identified differences in chromosome content between three strains with the hybrid AD serotype and revealed that chromosome 1 from the serotype A genome is preferentially retained in all three strains.The genomes of serotypes A, D, and AD strains exhibit extensive variation that spans the range from small differences (such as regions of divergence, deletion, or amplification) to the unexpected disomy for chromosome 13 in haploid strains and preferential retention of specific chromosomes in naturally occurring diploids.

Full Text

Duke Authors

Cited Authors

  • Hu, G; Liu, I; Sham, A; Stajich, JE; Dietrich, FS; Kronstad, JW

Published Date

  • January 2008

Published In

Volume / Issue

  • 9 / 2

Start / End Page

  • R41 -

PubMed ID

  • 18294377

Pubmed Central ID

  • 18294377

Electronic International Standard Serial Number (EISSN)

  • 1474-760X

International Standard Serial Number (ISSN)

  • 1474-7596

Digital Object Identifier (DOI)

  • 10.1186/gb-2008-9-2-r41

Language

  • eng