Novel CRISPR/Cas9 gene drive constructs reveal insights into mechanisms of resistance allele formation and drive efficiency in genetically diverse populations
Novel CRISPR/Cas9 gene drive constructs reveal insights into mechanisms of resistance allele formation and drive efficiency in genetically diverse populations
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DOI：
10.1371/journal.pgen.1006796
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发表时间：
2017-07-01
期刊：
影响因子：
4.5
通讯作者：
Messer, Philipp W.
中科院分区：
文献类型：
--
作者：
Champer, Jackson;Reeves, Riona;Messer, Philipp W.
一个有效的基因驱动系统可以从根本上改变我们控制病媒传播疾病的策略，促进转基因的快速传播，防止病原体传播或降低病媒能力。CRISPR/Cas9基因驱动承诺了这样一种机制，它通过将驱动构建体杂合的细胞转化为纯合子，从而实现超孟德尔遗传。尽管CRISPR基因驱动活性已经得到证实，但目前系统的一个关键障碍是它们倾向于产生抗性等位基因，而抗性等位基因不能转化为驱动等位基因。在这项研究中，我们开发了两种基于nanos和vasa启动子的CRISPR基因驱动构建体，使我们能够阐明在模式生物果蝇中形成抗性等位基因的不同机制。我们观察到由于母体沉积的Cas9，在生殖系中受精前和胚胎中受精后都以高速率形成抗性等位基因。在遗传多样性背景的驱动器活动的评估进一步揭示了转换效率和电阻率的显着差异。我们的研究结果表明，抗性的进化可能会严重限制目前CRISPR基因驱动方法的有效性，特别是当应用于不同的自然种群时。
A functioning gene drive system could fundamentally change our strategies for the control of vector-borne diseases by facilitating rapid dissemination of transgenes that prevent pathogen transmission or reduce vector capacity. CRISPR/Cas9 gene drive promises such a mechanism, which works by converting cells that are heterozygous for the drive construct into homozygotes, thereby enabling super-Mendelian inheritance. Although CRISPR gene drive activity has already been demonstrated, a key obstacle for current systems is their propensity to generate resistance alleles, which cannot be converted to drive alleles. In this study, we developed two CRISPR gene drive constructs based on the nanos and vasa promoters that allowed us to illuminate the different mechanisms by which resistance alleles are formed in the model organism Drosophila melanogaster. We observed resistance allele formation at high rates both prior to fertilization in the germline and post-fertilization in the embryo due to maternally deposited Cas9. Assessment of drive activity in genetically diverse backgrounds further revealed substantial differences in conversion efficiency and resistance rates. Our results demonstrate that the evolution of resistance will likely impose a severe limitation to the effectiveness of current CRISPR gene drive approaches, especially when applied to diverse natural populations.