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Self-structure induction in single stranded poly(A) by small molecules: Studies on DNA intercalators, partial
Prabal Giri1, Gopinatha Suresh Kumar
1Biophysical Chemistry Laboratory, Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Kolkata, West Bengal 700032, India.
Archives of Biochemistry and Biophysics
|April 5, 2008
Summary
Small molecules binding to single-stranded poly(A) can induce self-structure formation. Cooperative binding is key, with intercalators and some minor groove binders successfully inducing these structures.
Area of Science:
- Molecular Biology
- Biochemistry
- Structural Biology
Background:
- Single-stranded poly(A) can form self-structures.
- Small molecule binding is a known method to modulate nucleic acid structures.
Purpose of the Study:
- Investigate interactions between small molecules and poly(A).
- Identify structural features of small molecules responsible for poly(A) self-structure formation.
Main Methods:
- Absorption spectral titration
- Job plot analysis
- Isothermal titration calorimetry
- Circular dichroic melting
- Optical melting
- Differential scanning calorimetry
Main Results:
- Classical intercalators induced poly(A) self-structure.
- Partial intercalators did not induce self-structure.
- Hoechst 33258 induced self-structure, but DAPI did not.
- Self-structure induction correlated with cooperative binding.
Conclusions:
- Cooperative binding is essential for self-structure induction in poly(A).
- Specific molecular interactions, not just binding, dictate self-structure formation.
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