Verspieren P, Cornelissen A W, Thuong N T, Hélène C, Toulmé J J
Laboratoire de Biophysique, Muséum National d'Histoire Naturelle, INSERM U201, CNRS UA481, Paris, France.
Gene. 1987;61(3):307-15. doi: 10.1016/0378-1119(87)90194-6.
Anti-messenger oligodeoxynucleotides covalently linked to an intercalating agent were tested for their ability to inhibit translation of Trypanosoma brucei mRNAs in a cell-free system. The sequence of these oligodeoxynucleotides was complementary to part of the 35-nucleotide (nt) sequence which is present at the 5' end of all trypanosome mRNAs (the so-called mini-exon sequence). In a rabbit reticulocyte lysate, a nonadeoxynucleotide linked to an acridine derivative, specifically inhibited protein synthesis from T. brucei mRNAs much more efficiently than unmodified oligodeoxynucleotides of similar length. These oligodeoxynucleotides were tested on cultured trypanosomes. The acridine-linked nonadeoxynucleotide had a lethal effect on the parasites. No effect was observed with the homologous unmodified 9-mer nor with those 9-mers linked to the acridine derivative which were not complementary to the mini-exon sequence. These effects are probably a result of hybrid formation between the anti-messenger and mini-exon sequence. Trypanocidal activity of the acridine-modified nonadeoxynucleotide is most likely due to (i) increased affinity for its target, (ii) improved resistance to 3' exonucleases, and (iii) promoted membrane penetration of living parasites.
对与嵌入剂共价连接的反信使寡脱氧核苷酸在无细胞体系中抑制布氏锥虫mRNA翻译的能力进行了测试。这些寡脱氧核苷酸的序列与所有锥虫mRNA 5'端存在的35个核苷酸（nt）序列的一部分互补（即所谓的小外显子序列）。在兔网织红细胞裂解物中，与吖啶衍生物连接的十九脱氧核苷酸比类似长度的未修饰寡脱氧核苷酸更有效地特异性抑制布氏锥虫mRNA的蛋白质合成。在培养的锥虫上对这些寡脱氧核苷酸进行了测试。与吖啶连接的十九脱氧核苷酸对寄生虫有致死作用。同源未修饰的9聚体以及与吖啶衍生物连接但与小外显子序列不互补的9聚体均未观察到效果。这些作用可能是反信使与小外显子序列之间形成杂交的结果。吖啶修饰的十九脱氧核苷酸的杀锥虫活性很可能归因于：（i）对其靶标的亲和力增加；（ii）对3'核酸外切酶的抗性提高；（iii）促进活寄生虫的膜渗透。
