Puzzle 1
Sequence (5' to 3'): CCGCCGCGCCAUGCCUGUGGCGG
Puzzle: knowing that the crystal structure shows a homodimer that contains two strands of the sequence. The strands hybridize with blunt ends (C-G closing base pairs).
Crystal structure kindly provided by: Thomas Hermann
Reference: Dibrov SM, McLean J, Hermann T. 2011. Structure of an RNA dimer of a regulatory element from human thymidylate synthase mRNA, Acta Cryst. D, Biological Crystallography 67, 97-104.
PDB id: 3mei