Comparison of potassium ion preference of potassium-sensing oligonucleotides, PSO-1 and PSO-2, carrying the human and Oxytricha telomeric sequence, respectively.
Human [G(3)(TTAG(3))(3)] and Oxytricha [G(4)(T(4)G(4))(3)] telomere model oligonucleotides, PSO-1 and PSO-2, bearing two fluorophores, 6-carboxyfluorescein (6-FAM) and 6-carboxytetramethylrhodamine (6-TAMRA) at their 5'- and 3'-termini, respectively, were synthesized. Both of them can form an intramolecular antiparallel tetraplex upon addition of K(+), and an enhanced fluorescence resonance energy transfer (FRET) was observed. PSO-1 showed a 43,000 times higher selectivity for K(+) against Na(+). Fluorometric and circular dichroism spectrophotometric studies revealed that this system is useful for the evaluation of the interaction of different telomeric repeat oligonucleotide sequences with metal ions.
Takenaka
Shigeori
S
Department of Applied Chemistry, Faculty of Engineering, Kyushu University, Fukuoka 812-8581, Japan. staketcm@mbox.nc.kyushu-u.ac.jp
Ueyama
Hiroyuki
H
Nojima
Takahiko
T
Takagi
Makoto
M
D000818:Animals; D001483:Base Sequence; D015374:Biosensing Techniques; D002942:Circular Dichroism; D031541:Fluorescence Resonance Energy Transfer; D006801:Humans; D007477:Ions / Q000378:metabolism; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D016813:Oxytricha / Q000235:genetics*; D011188:Potassium / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism; D016615:Telomere / Q000235:genetics*
D007477:Ions; D009841:Oligonucleotides; D012964:Sodium; D011188:Potassium