KNL2 DNA Binding Is Competed out by Centromeric pAL1
ssRNA Transcript.
(A)
EMSA experiment with 8 pmol of pAL1
ssRNA (all lanes) and increased amounts of purified recombinant C-terminal KNL2 (8, 16, 20, 24, and 40 pmol in lanes 2–6, respectively; n = 3).
(B) Two radioactive EMSA experiments with 3.3 pmol labeled pAL1 (all lanes) and 26.6 pmol (upper gel) or 15 pmol (lower gel) purified recombinant C-terminal KNL2 (from lanes 2 to the rightmost). For the competition experiment, increasing amounts of pAL1
ssRNA forward transcript (upper gel, lanes 3–8: 1.5 and 3.3 pmol; 15, 33, 150, and 330 pmol; lower gel, lanes 3–10: 0.033 and 0.15 pmol; 0.33, 1.5, 3.3, 33, 150, and 330 pmol) or 330 pmol of 23-nucleotide ssRNA (last lane of each gel) were added. pAL1
ssRNA compete out the KNL2(C)-pAL1 DNA complex formation in contrast to the 23-nucleotide ssRNA. Forward and reverse pAL1 transcripts showed similar results (data not shown).