Fig 1.
Ploidy changes in pathogenic fungi.
(A) Colony and cellular morphologies of haploid and diploid forms of C. albicans (SC5314), C. auris (BJCA001), and C. glabrata (FK83). Cells were plated on YPD medium (BJCA001 and FK83 cells) or SCD medium (SC5314 cells) containing 5 μg/mL phloxine B and incubated at 30°C for 4 days. Scale bar for colonies, 5 mm; scale bar for cells, 5 μm. (B) Schematic diagram of ploidy changes. Fungal cells may undergo ploidy changes spontaneously or in response to environmental stresses. Cells of lower ploidy (e.g., haploid) can adopt a higher ploidy (diploid, tetraploid, or polyploid), which are subsequently able to return to the lower ploidy state through chromosome non-disjunction events that lead to concerted chromosome loss. Fungal cells are also able to switch between euploid and aneuploid states through gain or loss of chromosomes. Aneuploid and non-baseline ploidy states are often unstable and can give rise to additional genetic variants.