FIG. 8.
The Est1-RNP1-NC mutant protein can bind single-stranded telomeric DNA. Monoclonal antibody 12CA5 and protein A beads were mixed with extract from tagged (+) or untagged (−) Est1 strains (lanes 1 to 4). After washing was done, immunoprecipitates were challenged with a mixture of two end-labeled oligos, a 62-mer (EST1-RNP1C) of irrelevant sequence (Table 1) and a TG-rich, telomeric 27-mer (TELPG) (Table 1). Immunoprecipitates were then washed, and the bound oligos were assayed by phosphorimaging after gel electrophoresis. Lane 5 shows 1/20 the amount of the 27-mer–62-mer mixture that was added to the immunoprecipitates in the other lanes. The ratio of 27-mer to 62-mer is shown beneath the lanes.