Study On The Interaction Of New Ruthenium Or Rhodium Complexes With Triple Helix RNA

The RNA triple helix is a complex structure stabilized by multiple base trimers formed between an RNA double helix and a natural third strand or an artificial nucleic acid third strand.The pre-formed RNA duplex can accommodate the third strand and form a major-groove and a minor-groove triplex,respectively,without destroying the pre-formed duplex structure.Based on the above characteristics,it has been found that the RNA triplex is related to a series of biological functions.However,the stability of the third strand of the RNA triple helix is generally weaker than that of the parent duplex,which hinders its practical application under physiological conditions.Studies have shown that alternating the stability of the third strand with metal complexes has proven biologically significant.Therefore,this paper designs and synthesizes a series of metal complexes.Based on previous research,we further explore the binding properties of metal complexes and the RNA triple helix.This article introduces the basic knowledge about triple helix,and puts forward the vision of further exploring the interaction of complexes and RNA triplex in combination with the current research status.In this regard,a pair of ruthenium(Ⅱ)complexes [Ru(phen)2pip]2+(Ru1)and [Ru(dpq)2pip]2+(Ru2)with different ancillary ligands in different plane sizes was synthesized.The binding properties of Ru1 and Ru2 to the RNA triplex poly(U)·poly(A)*poly(U)have been investigated by various spectroscopic techniques and viscosity measurements.The experimental results show that both of the two complexes bind with the RNA triplex by intercalation mode,and Ru2 with a larger plane has a more pronounced stabilizing effect on the RNA triplex.Studies have shown that chiral complexes produce enantioselectivity when they interact with nucleic acids,which has aroused great interest.Therefore,complexes [Ru(bpy)2(o-HPIP)]2+,[Ru(bpy)2(m-NOPH)]2+ as well as [Ru(bpy)2(HNOIP)]2+were resolved chirally.The results show that all six complexes bind to the RNA triplex via intercalation,and Right-handed complexes were found to be more conducive to the RNA triple helix.Previous studies have shown that metallopeptides can improve RNA triplex stability because the positive charge on the metallopeptides can neutralize the electrostatic repulsion between the nucleic acid phosphate backbones.However,are all metal complexes modified with cationic oligopeptides capable of producing such a strong stabilizing effect on the RNA triple helix? To solve this problem,we designed and synthesized a pair of metallopeptides.The results show that lysine-rich metallopeptides are more conducive to RNA triple helix binding.In addition,the stability of these two complexes on the third strand is more pronounced than on the double helix,leading to the stability specificity.It can be found that previous studies were based on ruthenium complexes,but little is known about the binding properties of other metal complexes to the RNA triplex.So three rhodium(Ⅱ)complexes [Rh(bpy)2dpq]2+,[Rh(bpy)2dppz]2+,and [Rh(bpy)2(dppz-idzo)]2+were synthesized.The results show that these three rhodium complexes are combined with the RNA triplex by intercalation,and they all show extremely strong stabilizing effects on the triple helix,which is by far the most effective triplex stabilizer.