An.gambiae immune signaling gene SNPs and natural P. falciparum infection

冈比亚按蚊免疫信号基因SNPs与天然恶性疟原虫感染

• 批准号: 8602793
• 负责人: GREGORY C. LANZARO
• 金额: $ 56.97万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-01-15 至 2015-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8602793
• 关键词: Address; Affect; Africa South of the Sahara; Alleles; Anopheles gambiae; Cameroon; Cell Line; Cells; Central Africa; Chemicals; Chromosome inversion; Code; Codon Nucleotides; Country; Culicidae; Data; Development; Exhibits; Gene Conversion; Gene Targeting; Gene Transfer Techniques; Genes; Genetic; Genetic Polymorphism; Genetic Variation; Genotype; Geographic Distribution; Goals; Human; Immune; Immune response; Immune system; Immunity; In Vitro; Infection; Insulin; Karyotype; Laboratory Study; Light; Malaria; Mali; Maps; Mediating; Methods; Midgut; Molecular; Nature; O' nyong-nyong virus; Parasites; Phenotype; Plasmodium falciparum; Population; Population Genetics; Predisposition; Protocols documentation; Regulation; Sampling; Signal Pathway; Signal Transduction; Single Nucleotide Polymorphism; Site; Techniques; Testing; Transfection; Translations; Work; base; forest; gene function; genetic analysis; in vivo; inhibitor/antagonist; insight; interest; knock-down; novel; overexpression; protein function; protein structure; public health relevance; reproductive; response; screening; transmission process; vector

DESCRIPTION (provided by applicant): Significant data implicate the Toll/imd, insulin, and TGF-¿ signaling pathways in the regulation of malaria parasite development in the Anopheles gambiae midgut. However, no data are available to confirm that these signaling pathways regulate parasite development in nature. We have chosen to address this issue using a SNP association mapping approach with field-collected mosquitoes from Mali and Cameroon, countries with high malaria transmission that include the geographic distribution of the most genetically diverged An. Gambiae populations yet described. We will pursue this goal through two specific aims. The first Aim includes population genetic analyses. Plasmodium falciparum infected and uninfected An. gambiae will be collected from sites in Mali and Cameroon. These sites were carefully selected to include all of the genetic diversity known to exist in the region (three molecular forms and chromosome inversion polymorphism). Mosquito samples will be grouped by site with respect to infection, molecular form and karyotype. Each mosquito will then be genotyped for roughly 384 immune signaling gene SNPs and those SNPs correlated with infection identified by association mapping. This analysis will identify SNPs putatively involved in susceptibility to P. falciparum infection. In the second Aim, selected SNPs of interest will be analyzed to determine their effects on mosquito protein function and on susceptibility to P. falciparum infection. Specifically, we will utilize immortalized An. gambiae cell lines and a combination of over expression, knock-down, and gene conversion techniques to confirm predictions of function from sequence and to prioritize SNPs for in vivo studies. For the in vivo studies, we will use two genetically distinct strains of An. gambiae, which have been genotyped for the SNPs of interest. We will use inhibitors and transfection (knockdown, O'nyong-nyong infectious clone mediated overexpression) protocols to mimic the effects of SNP-containing alleles on P. falciparum development in infected mosquitoes. Our work will take functional data from our lab and from the labs of our colleagues to examine the importance of the selected immune signaling pathways in field-collected mosquitoes. In this light, the studies proposed herein will facilitate selection of appropriate gene targets for transgenesis strategies and provide critical new insights into the population genetics of immunity in An. gambiae that to our knowledge are not currently available.

描述（由申请人提供）：重要数据表明 Toll/imd、胰岛素和 TGF-β 信号通路在冈比亚按蚊中肠中疟原虫发育的调节中。然而，没有数据可以证实这些信号通路在自然界中调节寄生虫的发育。我们选择使用单核苷酸多态性 (SNP) 关联绘图方法来解决这个问题，该方法使用来自马里和喀麦隆的实地收集的蚊子，这两个国家是疟疾传播率较高的国家，其中包括遗传差异最大的蚊子的地理分布。冈比亚种群尚未描述。我们将通过两个具体目标来实现这一目标。第一个目标包括群体遗传分析。恶性疟原虫感染和未感染的 An。冈比亚将从马里和喀麦隆的地点收集。这些位点经过精心选择，包括该地区已知存在的所有遗传多样性（三种分子形式和染色体倒位多态性）。蚊子样本将按感染部位、分子形式和核型进行分组。然后，将对每只蚊子进行大约 384 个免疫信号基因 SNP 的基因分型，以及通过关联作图确定的与感染相关的 SNP。该分析将鉴定可能与恶性疟原虫感染易感性相关的 SNP。在第二个目标中，将分析选定的感兴趣的 SNP，以确定它们对蚊子蛋白功能和恶性疟原虫感染易感性的影响。具体来说，我们将利用不朽的An。冈比亚细胞系以及过度表达、敲低和基因转换技术的组合，以确认序列的功能预测并确定体内研究中 SNP 的优先顺序。对于体内研究，我们将使用两种遗传上不同的 An 菌株。冈比亚，已针对感兴趣的 SNP 进行了基因分型。我们将使用抑制剂和转染（敲低、O'nyong-nyong 感染性克隆介导的过度表达）方案来模拟含有 SNP 的等位基因对受感染蚊子中恶性疟原虫发育的影响。我们的工作将从我们的实验室和同事的实验室获取功能数据，以检查实地收集的蚊子中选定的免疫信号通路的重要性。有鉴于此，本文提出的研究将有助于为转基因策略选择适当的基因靶标，并为按蚊群体免疫遗传学提供重要的新见解。冈比亚 据我们所知，目前尚无法获得。