TABLE 1.
Purification of yeast telomerase
| Fraction | Protein (mg) | Activity (U)a | Fold purification | Cleavage/ extension ratio |
|---|---|---|---|---|
| Extract | 2,100 | ND | ||
| DEAE | 5.5 | 1,000 | 200b | 0.052 |
| Phenyl | 1.8 | 1,010 | 620 | 0.031 |
| Heparin | 0.19 | 270 | 1,560 | 0.051 |
| IgG | ∼0.010 | 140 | ∼15,400 | 0.026 |
a
Telomerase activity was determined in primer extension assays. Incorporation of labeled dGMP into RNase-sensitive bands was quantified using a PhosphorImager. The total activity of the DEAE fraction was arbitrarily set to 1,000, and the activities of the other fractions were calculated accordingly. ND, not determined.
b
The fold of purification for the DEAE fraction is based on the degree of Est2p enrichment as determined by Western analysis (Fig. 3B).