Secondary Structure of DNA DNA bending: involving several runs of five to six adenines(in the same strand), each separated by four or five bases, Inverted repeat: regions of DNA containing repeated sequences in inverse orientation, leading to a stem-loop(茎—环); Sticky end: DNA with single-strand complementary sequences at the end, this can form a hairpin, linear DNA can form a cycle with their sticky end These structures influence dna interaction with proteinsSecondary Structure of DNA DNA bending: involving several runs of five to six adenines (in the same strand), each separated by four or five bases; Inverted repeat: regions of DNA containing repeated sequences in inverse orientation, leading to a stem-loop (茎—环）; Sticky end: DNA with single-strand complementary sequences at the end, this can form a hairpin, linear DNA can form a cycle with their sticky end. These structures influence DNA interaction with proteins