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: 8205130
• 负责人: Heather Cristina Rowe
• 金额: $ 0.79万
• 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/8205130
• 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(申请人提供)：这项研究旨在提高对遗传距离较远的生物之间的杂交如何有助于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。其具体目标是：1)确定植物杂交物种复合体中特定类型的萜类代谢物的结构和含量多样性，比较自然存在的和实验创造的杂种，以及测量不同发育阶段和对胁迫刺激的反应的差异；2)确定特定生物合成酶结构的转录反应和功能变化如何影响这些天然和人工杂交物种复合体的代谢输出；以及3)确定萜类代谢物结构变异的遗传基础。将对亲本和杂交物种进行萜类结构的生化分析，使用修改现有的高效液相色谱-质谱分析和核磁共振分析方法。编码萜类化合物生物合成早期阶段的酶的遗传基因座将从现有的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转录积累的变异将通过标准测序方案和定量PCR进行测量。其他控制结构变异的候选基因座将通过构建图谱群体和与模式植物物种中鉴定的萜类化合物修饰基因座的同源性来确定，这些候选酶的活性通过在酵母和细菌系统中的异源表达来评估。来自不同亲本的基因组如何相互作用来创造独特的表型，这是一个生物学问题，对于理解包括人类在内的有性繁殖物种的生物特征的遗传基础和进化具有基本的重要性。植物系统对这类研究特别有用，因为种间杂交在遗传上是可行的，在伦理上也是允许的。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用途，有待探索的代谢表型还与公共健康相关。