Novel genetic and biological control methods for an invasive insect pest.

白纹伊蚊是一种入侵蚊种，在许多国家传播人(如登革热和基孔肯雅热)和家畜病毒。在过去十年里，它一直在欧洲稳步传播，人们担心，再加上气温上升，它可能是重大病毒流行的罪魁祸首。此外，蚊子会在白天造成严重的叮咬滋扰。它在美国南部和东部蔓延，现在是咬伤投诉的头号原因，随着人们花更多的时间在室内躲避，已经导致了人类行为的改变。因此，人们希望(1)减少人们被蚊子叮咬的频率，例如通过抑制蚊子种群和(2)减少蚊子种群的媒介能力。有了这样的工具，可以适当地应用其中一个或两个。抑制：大量释放不育雄性可以有效地、针对特定物种、对环境友好地抑制目标种群，并已在针对一些主要农业害虫的大规模项目中做到了这一点。遗传学的进步使基于遗传学的不育释放成为一种潜在的有吸引力的蚊子控制新策略(释放携带显性致死基因的昆虫)1-2。在埃及伊蚊获得成功后，我们正试图将这项技术转移到白纹伊蚊身上。到目前为止，我们已经成功地实现了转化，也有初步数据表明，我们可以实现必要的遗传学。学生将开发这项工作。降低的矢量能力：AE。自然界中的白纹伊蚊自然会感染两种遗传的细胞内细菌沃尔巴克氏菌。沃尔巴克氏杆菌可以利用细胞质不亲和性(CI)来操纵宿主繁殖达到自己的目的，从而提供了在种群中迅速传播的能力。最近发现，某些沃尔巴克氏菌株(包括果蝇中的wMel)能够阻止或减少各种病毒和丝虫线虫在果蝇和埃及伊蚊3，4中的发展或传播。这些数据对控制各种具有医学和农业意义的昆虫传播病原体具有重要意义。沃尔巴克氏菌的wmel菌株将从黑腹果蝇转移到四环素治愈的Ae品系。白纹伊蚊利用已建立的细胞质转移技术，选择了母体传播率高的品系，并在该品系中测试了对登革热和基孔肯雅传播的影响。CI和免疫状态将通过交叉和qRT-PCR表达分析进行分析。这些方法的一个统一特点是，它们都通过改良蚊子在野外与野生蚊子交配来产生影响。因此，影响这一点的品系性能的定量测量(例如交配竞争力、寿命、飞行能力、繁殖力等)将成为学生作业的重要部分；这些实验的数据将被用于对蚊子种群的数学模型进行参数化，并对更有希望的品系和策略进行成本效益分析。还将研究将RIDL和沃尔巴克氏菌方法相结合以开发创新的难治性加抑制策略的可能性。1 Thomas，D.D.，Donnelly，C.A.，Wood，R.J.&Alphey，L.S.使用优势的、可抑制的、致命的遗传系统控制昆虫种群。《科学》287,2474-2476(2000)。2Phuc，H.K.等人。后期作用的显性致死遗传系统和蚊子控制。生物医学中心生物学5，11，DOI：10.1186/1741-7007-5-11(2007年)。3 Kambra，Z.，Cook，P.E.，Phuc，H.K.&Sinkins，S.P.通过缩短沃尔巴克氏菌的寿命和降低蚊子的丝虫能力来激活免疫。科学326,134-136(2009)。4赫奇斯，L.M.，Brownlie，J.C.，O‘Neill，S.L.&Johnson，K.N.Wolbachia和昆虫中的病毒保护。《科学》322,702(2008)。

Aedes albopictus is an invasive mosquito species that transmits human (e.g. Dengue and Chikungunya) and livestock viruses in many countries. It has been spreading steadily through Europe over the course of the last decade, leading to fears that in combination with rising temperatures it may be responsible for major viral epidemics. Furthermore, the mosquito causes severe daytime biting nuisance. Its spread through the south and east USA, where it is now the number one cause of biting complaints, has led to human behavioural change as people spend more time indoors to avoid it. It would therefore be desirable to (i) reduce the frequency with which people are bitten by the mosquito, e.g. by suppressing the mosquito population and (ii) reduce the vectorial capacity of the mosquito population. With such tools, either or both could be applied, as appropriate. Suppression: Mass-release of sterile males can give effective, species-specific, environmentally friendly suppression of target populations, and has done so in large-scale programs against some major agricultural pests. Advances in genetics make genetics-based sterile-release a potentially attractive new strategy for mosquito control (Release of Insects carrying a Dominant Lethal gene, RIDL)1-2. Following success in Aedes aegypti2, we are attempting to transfer this technology to Aedes albopictus. So far we have successfully achieved transformation and also have preliminary data indicating that we can achieve the necessary genetics. The student will develop this work. Reduced vectorial competence: Ae. albopictus in nature are naturally infected with two strains of the inherited intracellular bacterium Wolbachia. Wolbachia can manipulate host reproduction to their own ends using cytoplasmic incompatibility (CI), providing an ability to spread rapidly through populations. It has recently been found that certain strains of Wolbachia (including wMel in Drosophila) are able to block or reduce the development or dissemination of various viruses and filarial nematode parasites in Drosophila and in Aedes aegypti mosquitoes3,4. These data have implications for the control of a variety of insect-borne pathogens of medical and agricultural importance. The wMel strain of Wolbachia will be transferred from D. melanogaster into a tetracycline-cured line of Ae. albopictus using established techniques of cytoplasm transfer, a line selected for high rates of maternal transmission, and effects on Dengue and Chikungunya transmission tested in this line. The CI and immune status will be analysed by crossing and qRT-PCR expression analyses. A unifying feature of these approaches is that they all have their impact via modified mosquitoes mating wild mosquitoes in the field. Quantitative measures of strain performance that would impact this (e.g. mating competitiveness, longevity, flight ability, fecundity, etc as appropriate) will therefore form a significant part of the student's work; data from these experiments will be used to parameterise mathematical models of mosquito populations and also cost-benefit analyses for the more promising strains and strategies. The possibility of combining RIDL and Wolbachia approaches to develop innovative refractory-plus-suppression strategies will also be examined. 1 Thomas, D. D., Donnelly, C. A., Wood, R. J. & Alphey, L. S. Insect population control using a dominant, repressible, lethal genetic system. Science 287, 2474-2476 (2000). 2 Phuc, H. K. et al. Late-acting dominant lethal genetic systems and mosquito control. BMC Biology 5, 11, doi:doi: 10.1186/1741-7007-5-11 (2007). 3 Kambris, Z., Cook, P. E., Phuc, H. K. & Sinkins, S. P. Immune activation by life-shortening Wolbachia and reduced filarial competence in mosquitoes. Science 326, 134-136 (2009). 4 Hedges, L. M., Brownlie, J. C., O'Neill, S. L. & Johnson, K. N. Wolbachia and virus protection in insects. Science 322, 702 (2008).