Defining the Impact of Intra-Species Diversity on C. albicans Biology

定义种内多样性对白色念珠菌生物学的影响

• 批准号: 9979250
• 负责人: Richard John Bennett
• 金额: $ 20.98万
• 依托单位: BROWN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-18 至 2022-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9979250
• 关键词: Address; Adult; Affect; Aneuploidy; Antibiotics; Antifungal Agents; Attention; Bar Codes; Behavior; Benign; Biology; Candida; Candida albicans; Chromosomes; Clinic; Clinical; Collection; Data; Diploidy; Disease; Enabling Factors; Epigenetic Process; Exhibits; Gastrointestinal tract structure; Genes; Genetic; Genetic Determinism; Genetic Variation; Genome; Genomics; Genotype; Human; Human body; Immunocompromised Host; In Vitro; Individual; Infection; Knowledge; Laboratories; Lead; Life; Life Style; Loss of Heterozygosity; Modeling; Mucous Membrane; Mus; Mycoses; Oral cavity; Outcome; Pathogenicity; Phenotype; Play; Population; Property; Quantitative Trait Loci; Recombinants; Role; Sepsis; Site; Skin; Source; Supplementation; Symbiosis; Systemic disease; Systemic infection; Techniques; Testing; Variant; Yeasts; clinically relevant; comparative genomics; de novo mutation; experience; experimental study; fitness; flexibility; gastrointestinal; genetic variant; genomic locus; genomic variation; gut colonization; high throughput analysis; in vivo; interest; microbiota; mortality; mouse model; pathogen; phenomics; reproductive tract; trait

Project Summary The yeast Candida albicans is a prevalent cause of life-threatening systemic disease in the clinic. This is a highly adaptive species with the ability to occupy diverse niches in the human body, either as a benign commensal or as an opportunistic pathogen. The diploid genome consists of eight heterozygous chromosomes that can undergo de novo mutation, loss of heterozygosity (LOH), or larger scale rearrangements including the acquisition or loss of whole supernumerary chromosomes. These mechanisms generate substantial variation in the population, yet there is currently limited understanding of how these natural differences effect interactions with the host. This project will examine how intra-species diversity impacts both the commensal and pathogenic properties of C. albicans. Preliminary experiments reveal that clinical isolates exhibit extensive genotypic differences and that additional microvariation occurs during passaging in the host. To determine how genetic diversity impacts C. albicans biology, a sequenced collection of clinical isolates will be barcoded and analyzed in different murine infection models. We hypothesize that different isolates will show optimal fitness in different host niches, and our studies will reveal those isolates that are hyper- or hypo-competitive for each niche. In parallel, a collection of SC5314 isolates will be barcoded and analyzed for phenotypic and genotypic differences. SC5314 is the standard “laboratory” isolate of C. albicans and yet preliminary data indicates diversity between isolates obtained from around the world. This reveals a critical need for a detailed analysis of the SC5314 collection to determine the level of genetic variation between strains and how this is affecting phenotypic properties. We will also perform a focused examination of differences in commensalism between two C. albicans isolates, SC5314 and 529L. SC5314 is unable to colonize the murine gastrointestinal tract (GI) in the absence of antibiotics, whereas we reveal that isolate 529L stably maintains GI colonization levels even without antibiotic supplementation. To identify genetic loci responsible for this difference, the two strains have been crossed to one another and recombinant progeny genotyped. These progeny will be used for quantitative trait loci (QTL) mapping to define the loci that underlie GI colonization properties and to understand how genetic variants impact commensalism. Together, these experiments will use high-throughput techniques to examine how genetic diversity in C. albicans populations impacts commensal and pathogenic interactions with the host, as well as a directed approach to examine factors enabling colonization of the GI tract. Our experiments will provide greater understanding of the role that genetic variation in C. albicans plays in infection outcomes, including the identification of mechanisms that promote adaptation to specific host niches.

项目摘要 白色念珠菌是诊所中威胁生命的全身性疾病的普遍原因。 这是一种高度适应性的物种 良性共生或作为机会性病原体。二倍体基因组由八个杂合子组成 可以从头突变，杂合性丧失（LOH）或更大规模的染色体 重排，包括收购或丢失整个超级染色体。这些 机制对人群产生了很大的差异，但目前的理解有限 这些自然差异如何影响宿主的相互作用。 该项目将研究种类内多样性如何影响共生和 白色念珠菌的致病特性。初步实验表明临床分离株展示 广泛的基因型差异和在宿主传递期间发生其他微交流的情况。 为了确定遗传多样性如何影响白色念珠菌生物学，这是一个测序的临床集合 分离株将在不同的鼠感染模型中进行条形码和分析。我们假设这一点 不同的分离株将在不同的宿主壁ches中表现出最佳的适应性，我们的研究将揭示这些选择 每个小众的分离株具有超竞争力或低竞争力。同时，SC5314分离株的集合 将对表型和基因型差异进行条形码和分析。 SC5314是标准 白色念珠菌的“实验室”孤立，但初步数据表明获得的分离株之间的多样性 来自世界各地。这揭示了对SC5314集合进行详细分析的迫切需要 确定菌株之间的遗传变异水平以及如何影响表型特性。 我们还将重点研究两个C之间的共生主义差异。 白色疾病分离株，SC5314和529L。 SC5314无法定居鼠胃肠道（GI） 在没有抗生素的情况下，我们揭示了分离株529L稳定地保持gi定殖水平 即使没有补充抗生素。为了确定造成这种差异的遗传位置，这两个 菌株已经彼此交叉并重组后代基因分型。这些后代将是 用于定量性状基因座（QTL）映射，以定义GI殖民特性的基因座 并了解遗传变异如何影响共生主义。 这些实验将共同使用高通量技术来检查遗传 白色念珠菌种群的多样性也影响与宿主的共生和致病性相互作用 作为实现胃肠道定殖的考试因素的定向方法。我们的实验会 提供对白色念珠菌在感染结果中发挥作用的作用的更多了解， 包括鉴定促进适应特定宿主生态位的机制。