Structural model of the 3'RR palindrome-driven internal hairpin. This figure shows (A) the linear map of human 3'RR2 and (B) the hairpin loop shape that this sequence can putatively assumes. The whole HS1.2 enhancer (i.e. core, 29 mer, 40 mers and 3'end sequence) is here sketched as orange box. We did not show the HS1.2 orientation in this graphic because it differs between the two copies of the 3'RR in human, and among the 3'RR of the species in Figure 5. The hypothetical hairpin structure is independent from the orientation of HS1.2.
D'Addabbo et al. BMC Evolutionary Biology 2011 11:71 doi:10.1186/1471-2148-11-71