The effects of the 4-(4-Methylpiperazine)phenyl group on nucleosides and oligonucleotides: cellular delivery, detection, and stability.
As drug candidates, one promising way to improve the cellular delivery efficacy of oligonucleotides is to introduce a cationic group. By introducing a cationic moiety into the oligonucleotide structure, they become capable of approaching the cell surface and also of crossing the cellular membrane. In an effort to develop cell-permeable oligonucleotides, we examined the piperazinephenyl-bearing 2'-deoxyuridine ((PP)U), which can be not only cationic but also fluorescent as a cationic monomer for cationic oligonucleotides. Several modified DNA oligonucleotides with different numbers of (PP)U building blocks were synthesized and evaluated for the effect on thermal stability and conformation by the introduction of (PP)U. The cellular delivery of modified oligonucleotides was different depending on the number of (PP)U building blocks. Furthermore, these (PP)U-modified oligonucleotides had sufficient fluorescence that we were able to identify the delivery results without the use of conventional fluorescent tags. They were predominantly localized in the cell cytoplasm. In addition, they were stable enough after 3 hours in the presence of nuclease. These results showed that a piperazinephenyl moiety that is conjugated with nucleobase is able to deliver and detect the oligonucleotides, which suggests that this concept of 'dual-function oligonucleotides' might be utilized in diagnostics, therapeutics, and as a convenient biological tool for probing the activity of oligonucleotides inside cells.
Department of Chemistry, BK School of Molecular Science, Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Republic of Korea.
Sun Min
SM
Park
Su-Jin
SJ
Nam
Hyun Seok
HS
Jeong
Won Jong
WJ
Kim
Byeang Hyean
BH
Kim
D002463:Cell Membrane Permeability; D003857:Deoxyuridine / Q000008:administration & dosage* / Q000031:analogs & derivatives* / Q000378:metabolism / Q000493:pharmacokinetics; D006367:HeLa Cells; D006801:Humans; D009841:Oligonucleotides / Q000008:administration & dosage* / Q000737:chemistry* / Q000378:metabolism / Q000493:pharmacokinetics; D000077489:Piperazine; D010879:Piperazines / Q000737:chemistry*
D009841:Oligonucleotides; D010879:Piperazines; D000077489:Piperazine; D003857:Deoxyuridine