Table 1. Effects of Htt-polyQ on cell growth.
| Htt-polyQ | Relevent genotype | Growth on glc, 1 day | Growth on gal, 1 day | Growth on gal, 2 days | Growth on gal, 3 days |
|---|---|---|---|---|---|
| Htt-25Q | Wild-type | + + + | + w − | + + + | + + + |
| Htt-47Q | Wild-type | + + + | + w− − | + + − | + + w |
| Htt-103Q | Wild-type | + + + | w− − − | + − − | + w − |
| Htt-103QP | Wild-type | + + + | + w− − | + + + | + + + |
| Htt-25Q | hsp104 | + + + | + w− − | + + + | + + + |
| Htt-103Q | hsp104 | + + + | + − − | + + + | + + + |
| Htt-25Q | ssa1 ssa2 | + + + | w − − | + w − | + + + |
| Htt-103Q | ssa1 ssa2 | + + + | w − − | + w − | + + + |
| Htt-25Q | pSSA1 | + + + | + w − | + + + | + + + |
| Htt-103Q | pSSA1 | + + + | + w − | + + w | + + + |
| Htt-25Q | pYDJ1 | + + + | +w w − | + + + | + + + |
| Htt-103Q | pYDJ1 | + + + | +w w− − | + w − | + + w |
| Htt-25Q | sir2 | + + + | + − − | + + − | + + w |
| Htt-103Q | sir2 | + + + | w− − − | + w − | + + − |
| Htt-25Q | Diploid | + + + | + +w − | + + + | + + + |
| Htt-103Q | Diploid | + + + | + − − | + w w− | + + + |
Note: Yeast strains were streaked into three successive diluted streaks of yeast cells as indicated from left to right in each panel. The growth characteristics refer to growth in each of these three successive diluted streaks of yeast cells (see Supplementary Figure 1 for an example). The first pool consisted of four to five toothpick streaks on the indicated medium from freshly grown cells pre-grown on glucose-containing medium. The second pool was made by choosing a new toothpick that was crossed through the first set of streaks to dilute the yeast before making another four to five streaks. Finally, a new toothpick was used to streak through this second group of streaks to further dilute the sample to obtain single cells by making another five or so streaks (third pool). Growth was on the appropriate selective plates either containing 2% glucose (glc) or 2% galactose (gal), as indicated. Growth was monitored one to three days after the initial streaking as indicated. ‘+’. Good growth; ‘w’. Weak growth. ‘−’. No growth. ‘+w’ and ‘w−’ refer to intermediate growths in the appropriate direction. Ability to continue to grow on galactose medium following 3 to 4 days of growth was also monitored for all strains. In this case, cells were picked from strains grown 3 to 4 days on medium containing galactose and restreaked on galactose containing medium. Only three strains failed to grow at all (indicating they were dead to begin with): wild-type cells containing Htt-103Q, cells overexpressing YDJ1 containing Htt-103Q (indicating that YDJ1 overexpression was unable to suppress Htt-103Q lethality), and cells containing the ssa1/ssa2 deletion with Htt-103Q. In this latter case, because the ssa1/ssa2 cells containing Htt-25Q grew, albeit poorly, the lethality of Htt-103Q with ssa1/ssa2 may partly be attributed to pleiotropic effects of deleting these two HSP70 genes.