9-Aminoellipticine-derivatized alpha- and beta-oligodeoxyribonucleotides targeted to the cap of beta-globin mRNA: hybridization to natural and engineered mRNA, inhibition of translation, and improved effect of tandem chains.
We studied the duplex stability and the antimessenger activity of 9-aminoellipticine-5'-functionalized alpha- and beta-anomeric DNA sequences complementary to the first 14 nucleotides of the rabbit beta-globin mRNA. The duplex formed by the beta-conjugate with the natural mRNA target possessed a marginally better stability to that of the duplex formed by the unfunctionalized compound, as measured by the thermal elution. The alpha-conjugate did not anneal to native mRNA, possibly due to the interference of the 9-aminoellipticine with the cap structure and, unlike the beta-adduct, was practically inactive as inhibitor of translation in a cell-free system. However, it did hybridize to an RNA construction containing the beta-globin mRNA plus an additional 50 bases in 5'. Surprisingly, translation from this construction was inhibited by the alpha-species in spite of the nonvicinity of the target to the cap. Both alpha and beta conjugates hybridized to a DNA 14-mer of the same sequence as that targeted onto the mRNA. Thermal denaturation and fluorescence spectroscopy showed that the drug brought no considerable stabilization to the duplex, the linker presumably being unfavorable to intercalation. An increased stability of the complex and a higher inhibitory effect on cell-free beta-globin translation were obtained with two contiguous beta-oligomers of which one was functionalized.
Porumb
H
H
Laboratoire de Biochimie-Enzymologie et de Physicochimie Macromoléculaire, CNRS URA 147, Institut Gustave Roussy, Villejuif, France.
Bertrand
J R
JR
Paoletti
J
J
Vasseur
J J
JJ
Rayner
B
B
Imbach
J L
JL
Malvy
C
C
D000818:Animals; D001483:Base Sequence; D002474:Cell-Free System; D004611:Ellipticines / Q000378:metabolism*; D005914:Globins / Q000235:genetics*; D007364:Intercalating Agents / Q000378:metabolism; D008969:Molecular Sequence Data; D009691:Nucleic Acid Denaturation; D009692:Nucleic Acid Heteroduplexes; D009693:Nucleic Acid Hybridization; D016376:Oligonucleotides, Antisense / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010957:Plasmids; D014176:Protein Biosynthesis; D012315:RNA Caps / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011817:Rabbits; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature
D004611:Ellipticines; D007364:Intercalating Agents; D009692:Nucleic Acid Heteroduplexes; D016376:Oligonucleotides, Antisense; D012315:RNA Caps; D012333:RNA, Messenger; C038373:9-aminoellipticine; D005914:Globins