The results show that Cu2+ breaks the hydrogen bonds within Hoogsteen and Watson-Crick base pairs through binding to the bases of poly (A: 2I) and makes the triple helix poly(A: 2I) unwound irreversibly.

• 结果表明：Cu（2＋）通过与poly（A：2I）中的碱基的结合，破坏了Hoogsteen碱基对和Watson－Crick碱基对中的氢键，从而导致了三螺旋poly（A：2I）不可复性的解旋。