Engineering a Minimal Drive System for Vector Control in Drosophila melanogaster

疟疾、黄热病、登革热等人类疾病通过媒介传播给全球卫生造成的巨大负担，决定了需要新的有效的控制方法。一种这样的方法是遗传驱动的方法，促进对常见媒介(例如蚊子、采采蝇、扁虱等)进行种群一级的修改。基因驱动允许研究人员重新利用自然产生的转座元件作为一种手段，以高于孟德尔的速度人为地推动群体世代之间所需特征的遗传率。这样，就有可能传播效应器基因，从而提供一种抑制疾病发病机制的手段。与使用化学杀虫剂等现有病媒控制策略相比，这种方法具有显著的优势，后者主要是临时性的，需要大量的后勤和经济承诺。基因驱动是一种自我维持的替代选择，可以永久地解决人类健康面临的众多挑战。合成的基因驱动系统已被描述为在种群中繁殖所需特征的各种机制。一种这样的机制利用编码位点特异性核酸内切酶的基因作为一种手段来快速驱动效应基因的遗传。基因编码的核酸酶在目标基因组位置产生双链断裂，随后被用作同源修复的模板。这会导致杂合子个体成为该基因的纯合子--该基因被插入到其自身识别序列的中间，防止新修复的位置成为进一步的靶点。这样的核酸酶编码基因可以被设计成携带货物，通过这种方式，效应基因的频率可以增加并传递给宿主生物体的后代。基因工程的最新进展导致了新型合成内切酶的产生，这种酶可以被设计成专门切割基因组序列。自那以后，已经使用锌指、TALENS和CRISPR核酸酶展示了合成基因驱动系统的例子。我们现在想要进一步优化这种合成基因驱动，以便设计出一个最小的系统，提供比现有设计更多的优势。我们的目标是在果蝇身上开展这项工作。这种模式生物对一系列目标节肢动物具有显著的基因组保守性，使其成为评估这一新系统的效率并允许高通量实验的有力平台。通过这种方式，我们的目标是设计和设计一种新型的合成基因驱动系统。此外，通过研究黑腹葡萄球菌的基因驱动，我们将为在一系列载体中实施这一驱动提供一条途径，使未来的工作能够针对医疗保健以外的部门的相关生物，如农业。

The significant burden exerted on global health by vector-borne transmission of human diseases such as malaria, yellow fever, dengue fever and others has dictated the need for novel and effective control methodologies. One such methodology is that of a genetic drive, facilitating population-level modification of common vectors (e.g. mosquitoes, tsetse flies, ticks, etc...). Gene drive permits researchers to repurpose naturally occurring transposable elements as a means to artificially drive the rate of inheritance of desired traits between generations of a population at a greater-than Mendelian rate. In so doing, it is possible to spread effector genes that may offer a means to inhibit disease pathogenesis. This methodology offers notable advantages over existing vector control strategies such as use of chemical pesticides, which are largely temporal and require significant logistical and economical commitment. Gene drive is a self-sustaining alternative that can be implemented to permanently address numerous challenges to human health.Synthetic gene drive systems have been described with a variety of mechanisms for the proliferation of desirable traits across a population. One such mechanism makes use of genes encoding site-specific endonucleases as a means to rapidly drive inheritance of effector genes. The gene-encoded nuclease generates a double-stranded break in a targeted genomic site, and is subsequently used as a template for homologous repair. This results in heterozygous individuals becoming homozygous for the gene - the gene is inserted into the middle of its own recognition sequence, preventing the newly repaired site from being further targeted. Such nuclease-encoding genes can be engineered to carry a cargo, and in this way frequency of the effector gene can increase and be transmitted to the host organism's progeny. Recent advances in genetic engineering have resulted in new classes of synthetic endonucleases that can be designed to specifically cleave genomic sequences. Examples of synthetic gene drive systems have since been demonstrated using Zinc-finger, TALENs and CRISPR nucleases. We now want to further optimise this synthetic gene drive in order to engineer a minimal system, offering numerous advantages over existing designs. We aim to undertake this work in Drosophila melanogaster. This model organism has significant genomic conservation to a range of target arthropods, making it a potent platform for evaluating the efficiency of this novel system, and permitting high-throughput experimentation. In this way we aim to design and engineer a novel synthetic gene drive system. Furthermore, by investigating gene drive in D. melanogaster, we will provide an avenue for implementation of this drive in a range of vectors, allowing future work to be targeted to relevant organisms in sectors outside of healthcare, such as agriculture.