Figure 3.

Three examples of humanized yeast, relevant to neurodegenerative disorders, metabolic disorders and cholesterol biosynthesis. (A) (Left) Yeast show diffuse distribution of α-synuclein during moderate expression (NoTox), aggregation during overexpression (HiTox) and rescue of aggregation by administration of an N-aryl benzimidazole (NAB). (Right) Degeneration (white arrowheads) of C. elegans DA neurons during overexpression of α-synuclein (top) and protection by NAB administration (bottom). Figures are adapted from Tardiff et al. [30] with permission. (B) (top) Growth over time of Δcys4 yeast expressing the major human allele of cystathione-β-synthase (CBS) as a function of varying concentrations of vitamin B6. (bottom) Growth rate at various levels of vitamin B6 for several minor human alleles, relative to the major human allele. Figures are adapted from Mayfield et al. [31] with permission. (C) Seventeen of 19 tested genes of the yeast sterol biosynthesis pathway are replaceable by their human equivalents. Figure adapted from Kachroo et al. [6] with permission. (A colour version of this figure is available online at: http://bfg.oxfordjournals.org)