An experimental and theoretical study of the inhibition of Escherichia coli lac operon gene expression by antigene oligonucleotides
An experimental and theoretical study of the inhibition of Escherichia coli lac operon gene expression by antigene oligonucleotides
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DOI：
10.1002/bit.1111
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发表时间：
2001-08-05
影响因子：
3.8
通讯作者：
Schisler, J
中科院分区：
文献类型：
--
作者：
Cheng, B;Fournier, RL;Schisler, J
在此之前，我们已经建立了一个遗传结构数学模型来描述抗原寡聚物对大肠杆菌lac操纵子基因表达的抑制。我们的模型预测，针对lac操纵子的操作区域的抗原寡核苷酸将对β -半乳糖苷酶的产生产生显著的抑制作用。本研究通过实验研究了抗原寡核苷酸存在下大肠杆菌lac操纵子基因的表达。一个21聚寡核苷酸，被设计成与操作者形成三倍体，被发现能够以剂量依赖的方式特异性抑制p -半乳糖苷酶的产生。与21聚三聚体形成寡核苷酸（TFO）相比，一些对照寡核苷酸没有抑制作用。各种控制寡核苷酸的无效，以及21-mer寡核苷酸与lacZYA没有同源序列，并且没有从操作员转录的mRNA，表明21-mer寡核苷酸通过抗原机制抑制靶基因的表达。为了模拟抗原寡核苷酸存在时lac操纵子基因表达的动力学，建立了一个遗传结构动力学模型，包括寡核苷酸进入细胞的运输、细菌细胞的生长和lac操纵子基因的表达。在调整了寡核苷酸输运速率常数(9.0 × 10（-3) min(-1)）和寡核苷酸结合亲和常数（1.05 × 10(6) M-1）后，动力学模型的预测与实验数据非常吻合。我们对这两个调整后的参数的值在文献报道值的范围内。(C) 2001约翰威利父子公司
Previously, we have developed a genetically structured mathematical model to describe the inhibition of Escherichia coli lac operon gene expression by antigene oligos. Our model predicted that antigene oligos targeted to the operator region of the lac operon would have a significant inhibitory effect on beta -galactosidase production. In this investigation, the E. coli lac operon gene expression in the presence of antigene oligos was studied experimentally. A 21-mer oligo, which was designed to form a tripler with the operator, was found to be able to specifically inhibit P-galactosidase production in a dose-dependent manner. In contrast to the 21-mer tripler-forming oligonucleotide (TFO), several control oligos showed no inhibitory effect. The ineffectiveness of the various control oligos, along with the fact that the 21-mer oligo has no homology sequence with lacZYA, and no mRNA is transcribed from the operator, suggests that the 21-mer oligo inhibits target gene expression by an antigene mechanism. To simulate the kinetics of lac operon gene expression in the presence of antigene oligos, a genetically structured kinetic model, which includes transport of oligo into the cell, growth of bacteria cells, and lac operon gene expression, was developed. Predictions of the kinetic model fit the experimental data quite well after adjustment of the value of the oligonucleotide transport rate constant (9.0 x 10(-3) min(-1)) and oligo binding affinity constant (1.05 x 10(6) M-1). Our values for these two adjusted parameters are in the range of reported literature values. (C) 2001 John Wiley & Sons, Inc.