The genetic bases of secondary metabolite diversity in a hybrid species complex

杂种复合体次生代谢物多样性的遗传基础

• 批准号: 8207665
• 负责人: Heather Cristina Rowe
• 金额: $ 4.43万
• 依托单位: UNIVERSITY OF BRITISH COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8207665
• 关键词: Biochemical; Biological; Complex; Control Locus; DNA Sequence; Development; Distant; Engineering; Enzymes; Evolution; Genetic; Genome; Genomics; Goals; High Pressure Liquid Chromatography; Human; Hybrids; Investigation; Lactones; Literature; Maps; Measurement; Measures; Messenger RNA; Metabolic; Modification; Organism; Output; Parents; Pathway interactions; Pharmacologic Substance; Phenotype; Plant Model; Plants; Population; Production; Protocols documentation; Public Health; Research; Sesquiterpenes; Shapes; Side; Staging; Stimulus; Stress; Structure; System; Terpenes; Terpenoid Biosynthesis Pathway; Therapeutic Uses; Transcript; Variant; Yeasts; base; improved; interest; member; novel; pressure; response; trait

DESCRIPTION (provided by applicant): This research is proposed to improve understanding of how hybridization between genetically distant organisms contributes to the evolution of novel phenotypes and how environmental pressures shape the resultant phenotypic diversity. The specific aims are: 1) to determine structural and content diversity of specific classes of terpenoid metabolites in plant hybrid species complexes, with comparison of naturally- existing and experimentally-created hybrids as well as measurement of variation across development and in response to stress stimuli; 2) to determine how variation in transcriptional response and functional variation in structure of specific biosynthetic enzymes impacts the metabolic output of these natural and artificial hybrid species complexes; and 3) to identify the genetic bases of structural variation in terpenoid metabolites. Biochemical analyses of terpene structures will be conducted on parental and hybrid species using modifications of existing analytical protocols for HPLC-MS and NMR. Genetic loci encoding enzymes responsible for early stages of terpenoid biosynthesis will be identified from existing literature or via homology to known enzymes. Variation in DNA sequence and mRNA transcript accumulation for these specific enzymes will be measured via standard sequencing protocols and quantitative PCR. Additional candidate loci controlling structural variation will be identified using structured mapping populations and homology to terpenoid modification loci identified in model plant species, with activity of these candidate enzymes evaluated via heterologous expression in yeast and bacterial systems. How genomic contributions from diverse parents interact to create unique phenotypes is a biological question of basic importance to understanding the genetic bases and evolution of biological traits in sexually-reproducing species, including humans. Plant systems are particularly useful for such studies as interspecific crosses are both genetically feasible and ethically permissible. The metabolic phenotypes to be explored are additionally relevant to public health due to the allergenicity and potential therapeutic uses of terpenoid metabolites, and the potential utility of these studies in metabolic engineering.

描述（由申请人提供）：这项研究旨在增进对遗传距离较远的生物之间的杂交如何促进新表型的进化以及环境压力如何塑造由此产生的表型多样性的理解。具体目标是：1）通过比较天然存在的和实验创建的杂交品种以及测量发育过程中的变化和对胁迫刺激的反应，确定植物杂交物种复合体中特定类别萜类代谢物的结构和含量多样性； 2) 确定转录反应的变化和特定生物合成酶结构的功能变化如何影响这些天然和人工杂交物种复合物的代谢输出； 3) 鉴定萜类代谢物结构变异的遗传基础。将使用对现有 HPLC-MS 和 NMR 分析方案的修改，对亲本和杂交物种进行萜结构的生化分析。编码负责萜类生物合成早期阶段的酶的基因座将从现有文献中或通过与已知酶的同源性来鉴定。这些特定酶的 DNA 序列和 mRNA 转录物积累的变化将通过标准测序方案和定量 PCR 进行测量。将使用结构化作图群体和与模型植物物种中鉴定的萜类修饰基因座的同源性来鉴定控制结构变异的其他候选基因座，并通过酵母和细菌系统中的异源表达来评估这些候选酶的活性。来自不同父母的基因组贡献如何相互作用以创造独特的表型是一个生物学问题，对于理解包括人类在内的有性繁殖物种的遗传基础和生物性状的进化具有基本重要性。植物系统对于此类研究特别有用，因为种间杂交在遗传上是可行的并且在伦理上是允许的。由于萜类代谢物的过敏性和潜在的治疗用途，以及这些研究在代谢工程中的潜在效用，待探索的代谢表型还与公共健康相关。