Dear Prof, (you are expert in your own field)

Abstractz:

The influence of acyclic RNA derivatives, UNA (unlocked nucleic acid) monomers, on i-DNA thermodynamic stability has been investigated. The 22nt human telomeric fragment was chosen as the model sequence for stability studies. UNA monomers modulate i-motif stability in a position-depending manner. The largest destabilization is observed for position C14, while UNA placed in position A12 causes significant increase of i-DNA thermodynamic stability. CD curves of UNA-modified variants imply no structural changes relative to the native i-motif.

REF:Modulation of i-motif thermodynamic stability by the introduction of UNA (unlocked nucleic acid) monomers. by Prof. Anna Pasternak

Biorganic & medicinal chemistry letters (Impact Factor: 2.65). 01/2011; 21(2):752-5. : 

Well, maybe I didn't ask my question clearly enough - sorry for that. I was wondering what kind of solution components can increase thermodynamic stability of i-motif structure (except pH) e.g. salt concentration, different ions, molecular crowding etc.. The paper that you refered to concerns only the influence of UNAs on i-motif stability - i-motif structure is modified "internally" by other kind of nucleoside residues.

Hi Anna,

Have a look at the review I have co-authored, "i-Motif DNA: Structure, Stability and Targeting with Ligands" in Bioorganic and Medicinal Chemistry 2014. The literature suggests that some cations destabilise the i-motif while molecular crowding appears to stabilise the  i-motif however there is still a lot of work to be done in this area.

Article I-Motif DNA: Structure, stability and targeting with ligands

Many thanks Henry! I'll take a look at the review!

We've also looked at silver cations, showing that they enable i-motif formation at neutral pH.

Article Silver cations fold i-motif at neutral pH

Thanks a lot Henry :)

Hi Anna,

Incase you're interested, we've just published our results on Copper interacting with i-motif.

Article Reversible DNA i-Motif to Hairpin Switching Induced by Coppe...

Hi Henry,

Many thanks for giving me a hint. I will be pleased to go through it.

Thanks for remembering me!!!