I am reading the paper:
Petersheim, M. and Turner, D.H. (1983) Base-stacking and base-pairing contributions to helix stability: thermodynamics of double-helix formation with CCGG, CCGGp, CCGGAp, ACCGGp, CCGGUp, and ACCGGUp. Biochemistry, 22, 256-263.
The p at the end of the sequence apparently stands for 3'-terminal phosphate.
What is the difference between RNA sequences with a 3' terminal phosphate and a "normal" RNA sequence? Why would they consider RNA with a 3' terminal phosphate?