The Small Molecular Interactions With The G-quadruple And Its Biological Applications

This paper mainly carries out around the G-quadruple interacting with small fluorescent molecules.In the first part of the paper,we mainly engaged in the research of 3-Hydroxyflavone molecules interacting with G-quadruple.Due to the 3-Hydroxyflavones are sensitive to the biological environment,therefore,we assume to be used to distinguish between the G-quadruple and single-stranded or double-stranded DNA.Through the ultraviolet spectrum,fluorescence spectrum,circular dichroism,polyacrylamide gel electrophoresis and molecular docking experiment,we have studied the interaction of two small molecules with DNA.The results show that the G-quadruple can make the fluorescence of small molecules enhancement significantly,while dsDNA and ssDNA has no obvious effect.Based on this,we realized the fluorescence detection of G-quadruple successfully.In addition,we also studied the pattem of combination between G-quadruple and small molecules,it shows that small molecules can make the G-quadruple stable.On this basis,we also developed the fluorescence probe of hydrogen sulfide,the probe has a lower detection limit to hydrogen sulfide in the presence of G-quadruple,which can be used in the detection of hydrogen sulfide in the nuclei potentially.Thioflavin T(ThT)can make the fluorescence enhanced markedly when interacting with G-quadruple or ?-amyloid plaques(A?).A? gathered in the brain and its nerve toxicity was the main reason of Alzheimer's disease(AD).In the second part of this paper,Through the polyacrylamide gel electrophoresis and fluorescence spectrum experiments,we studies the relationship of G-quadruple and the aggregation of A?,the results show that the G-quadruple can impact the gather of A?.In the short time the G-quadruple can promote A? gather.But in certain degree G-quadruple can inhibits A? from gather again.So G-quadruple can regulate gatheration of A?.