Figure 4.

Determination of the consensus sequence for the second endonucleolytic nicking sequence. The top panel shows χ² values at the indicated positions relative to the nicking site (see Jurka, 1997 for detailed description of methodology). χ² values above the horizontal graded line at χ²=16.27 are significant at the p=0.001 level. Nucleotide composition at each position relative to the predicted nicking site is shown in the bottom panel. At positions −1, −3, and −5, no nucleotide is significantly over-represented (“N”). At positions +1, +2, and −6 “A” is unambiguous. “T” has the highest χ² at positions −2 and −4. Horizontal lines in the bottom panel show the mean composition of the 3′ flanking regions of the elements studied, identified by nucleotide letter on the right-side axis.