One of the most powerful approaches to understanding gene function involves turning genes on and off at will and measuring the impact at the cellular or organismal level. This particularly applies to the cohort of essential genes where traditional gene knockouts are inviable. In Plasmodium falciparum, conditional control of gene expression has been achieved by using multicomponent systems in which individual modules interact with each other to regulate DNA recombination, transcription, or posttranscriptional processes. The recently devised TetR-DOZI aptamer system relies on the ligand-regulatable interaction of a protein module with synthetic RNA aptamers to control the translation of a target gene. This technique has been successfully employed to study essential genes in P. falciparum and involves the insertion of several aptamer copies into the 3′ untranslated regions (UTRs), which provide control over mRNA fate. However, aptamer repeats are prone to recombination and one or more copies can be lost from the system, resulting in a loss of control over target gene expression. We rectified this issue by redesigning the aptamer array to minimize recombination while preserving the control elements. As proof of concept, we compared the original and modified arrays for their ability to knock down the levels of a putative essential apicoplast protein (PF3D7_0815700) and demonstrated that the modified array is highly stable and efficient. This redesign will enhance the utility of a tool that is quickly becoming a favored strategy for genetic studies in P. falciparum.

中文翻译：

---

重新设计的 TetR-适配体系统以控制恶性疟原虫中的基因表达。

理解基因功能的最有效方法之一是随意打开和关闭基因，并测量细胞或生物体水平的影响。这尤其适用于传统基因敲除无法生存的必需基因组群。在恶性疟原虫中，基因表达的条件控制是通过使用多组件系统实现的，其中各个模块相互交互以调节 DNA 重组、转录或转录后过程。最近设计的 TetR-DOZI 适配体系统依赖于蛋白质模块与合成 RNA 适配体的配体可调节相互作用来控制目标基因的翻译。该技术已成功用于研究恶性疟原虫的必需基因并且涉及将几个适体拷贝插入 3' 非翻译区 (UTR)，从而控制 mRNA 的命运。然而，适配体重复容易发生重组，系统中可能会丢失一个或多个拷贝，从而导致失去对目标基因表达的控制。我们通过重新设计适体阵列以在保留控制元素的同时最小化重组来纠正这个问题。作为概念证明，我们比较了原始阵列和修改后的阵列降低推定必需顶质体蛋白 (PF3D7_0815700) 水平的能力，并证明修改后的阵列高度稳定和高效。这种重新设计将增强工具的实用性，该工具正迅速成为恶性疟原虫遗传研究的首选策略。