Wu-Pong S, Weiss T L, Hunt C A
Department of Pharmaceutical Chemistry, University of California, San Francisco 94143.
Antisense Res Dev. 1994 Fall;4(3):155-63. doi: 10.1089/ard.1994.4.155.
Previously described cell membrane transport mechanisms are unable to account completely for oligodeoxynucleotide cellular uptake. These charged macromolecules enter cells by an incompletely defined mechanism and downregulate gene expression in either the cytoplasm or nucleus. Thus, the goal of this research was to study the mechanism of phosphodiester oligonucleotide cellular uptake in Rauscher Red 5-1.5 erythroleukemia cells. An antisense c-myc oligodeoxynucleotide (21 bases) demonstrated biological activity in these cells using two types of proliferation assays and Northern blot analysis, and was internalized as visualized by confocal laser microscopy. Oligonucleotide uptake appeared to be a complex process consisting of surface binding and internalization. Cellular internalization accounted for up to 40% of total uptake and was partially dependent on both a trypsin-sensitive component and cellular energy. Uptake in these cells was nonspecific and did not appear to be due to receptor-mediated endocytosis. Therefore, because oligonucleotide cellular uptake in other cell types apparently involves an endocytic mechanism, the primary mechanism of oligonucleotide internalization may be cell line dependent.
先前描述的细胞膜转运机制无法完全解释寡脱氧核苷酸的细胞摄取过程。这些带电荷的大分子通过一种尚未完全明确的机制进入细胞，并在细胞质或细胞核中下调基因表达。因此，本研究的目的是探讨磷酸二酯寡核苷酸在劳舍尔红5 - 1.5红白血病细胞中的摄取机制。一种反义c - myc寡脱氧核苷酸（21个碱基）通过两种增殖试验和Northern印迹分析在这些细胞中显示出生物学活性，并通过共聚焦激光显微镜观察到其被内化。寡核苷酸摄取似乎是一个由表面结合和内化组成的复杂过程。细胞内化占总摄取量的40%，并且部分依赖于胰蛋白酶敏感成分和细胞能量。这些细胞中的摄取是非特异性的，似乎不是由受体介导的内吞作用引起的。因此，由于寡核苷酸在其他细胞类型中的细胞摄取显然涉及内吞机制，寡核苷酸内化的主要机制可能取决于细胞系。
