Table 1.
Effects of various hMLH1 HNPCC missense mutations on protein interaction
|
β-gal activity (units±s.e.) (Gal4-AD fusion) |
||
|---|---|---|
| hMLH1 (495–756 LexA-BD) | hMRE11 | hPMS2 |
| Wild type | 128.89±10.27 | 192.77±14.00 |
| Q542L | 93.21±7.84 | 164.55±12.72 |
| L574P | 4.25±0.29 | 3.91±0.29 |
| E578G | 124.92±7.29 | 145.01±14.16 |
| L582V | 99.72±8.57 | 191.83±10.49 |
| K618T | 4.22±0.44 | 80.45±1.62 |
| R659P | 2.64±0.27 | 3.62±0.24 |
| A681T | 2.47±0.32 | 90.23±7.65 |
| R659P/A681T | 2.69±0.36 | 3.53±0.09 |
β-Galactosidase activity was determined with the β-gal liquid assay using ONPG as a substrate. The coding sequences for wild-type hMLH1 aa 495–756 and various missense mutants were fused to LexA-BD in plasmid pBTM116. R659P/A681T is a double mutant containing two independent mutations. Full-length hMRE11 and hPMS2 proteins were fused with Gal4-AD in plasmid pGADT7. Analysis of protein interaction was carried out in reporter strain L40. The average β-gal activity units and standard errors (s.e.) were determined with at least three independent data points.