Table 1. Summary of phenotypes of Set1+ cells, set1Δ cells and Set1 mutants.
| Classa | Substitutionb | in vivo methylation H3K4c | rDNA silencingTy1his3AI/PYK1 d | Suppression ofipl1-2 e | ||
| K4me1 | K4me2 | K4me3 | ||||
| null | Y967A | 0.05+/−0.04 | 0 | 0 | 13.0+/−5.5, n = 6 | Yes |
| null | N1016A | 0 | 0 | 0 | 5.1+/−2.6, n = 6 | Yes |
| null | H1017L | 0.01+/−0.01 | 0 | 0.01+/−0.01 | 5.0+/−1.8, n = 7 | Yes |
| null | H1017R | 0.03+/−0.02 | 0.01 | 0 | 4.0+/−1.5, n = 4 | Yes |
| null | Y1054A | 0 | 0 | 0 | 3.3+/−0.7, n = 3 | Yes |
| null | F1056A | 0 | 0 | 0 | 6.8+/−2.8, n = 7 | Yes |
| partial func/null | G951A | 0.70+/−0.14 | 0.02+/−0.01 | 0 | 8.1+/−3.9, n = 6 | partial-yes |
| partial func/null | Y993A | 0.49+/−0.06 | 0.06+/−0.04 | 0 | 8.0+/−3.2, n = 5 | partial-yes |
| partial func/silent | Y967F | 0.50+/−0.05 | 0.01 | 0.04+/−0.03 | 2.0+/−1.0, n = 6 | partial-no |
| partial func/silent | R1013H | 1.33+/−0.02 | 0.54+/−0.05 | 0.02+/−0.01 | 2.8+/−0.3, n = 3 | partial-no |
| partial func/silent | Y1054F | 0.45+/−0.07 | 0.28+/−0.04 | 0.03+/−0.01 | 1.7+/−0.2, n = 3 | partial-no |
| silent | H1017A | 1.52+/−0.14 | 1.98+/−0.30 | 3.18+/−1.46 | 1.0+/−0.3, n = 4 | No |
| silent | Y1052F | 0.56+/−0.02 | 0.84+/−0.16 | 1.49+/−0.33 | 1.0+/−0.1, n = 6 | No |
| silent | Y1052A | 0.35+/−0.16 | 0.59+/−0.11 | 1.05+/−0.23 | 0.8+/−0.2, n = 6 | No |
| silent | Y1052V | 0.63+/−0.20 | 1.24+/−0.30 | 2.70+/−0.74 | 1.0+/−0.3, n = 6 | No |
| silent | F1056Y | 0.96+/−0.06 | 0.92+/−0.17 | 1.20+/−0.50 | 0.8+/−0.1, n = 3 | No |
| Wild type Set1+ | None | 1 | 1 | 1 | 1 | No |
| set1Δ | deletion | 0 | 0 | 0 | 5.4+/−1.7, n = 30 | Yes |
For details of classification, see text; partial func/null, partial function with phenotypes more similar to set1Δ cells; partial func/silent, partial function with phenotypes more similar to Set1+ cells.
Amino acid substitution in Set1.
Average levels +/− range of H3K4me1, H3K4me2 and H3K4me3 measured in whole cell extracts from Set1 mutants by quantitative western blotting (n = 2); values are normalized to the levels measured in whole cell extracts from a wild type Set1+ strain. No value for +/− range is given if the two measurements were identical. See Figure 3 and text for details.
Pol II gene silencing at the rDNA was assessed by measuring the level of Ty1his3AI mRNA/PYK1 mRNA in total RNA relative to that from a Set1+ strain where the ratio of Ty1his3AI/PYK1 was set to 1. The values shown are average +/− SD for n repeats.
Suppression of ipl1-2 growth defects at the restrictive temperature (30°C) was measured in growth assays described in the text and shown in Figure 5. Yes, growth at 30°C; No, severely reduced growth at 30°C; partial-yes, slightly reduced growth at 30°C; partial-no, intermediate reduction of growth at 30°C.