The Regulatory Disruption Hypothesis for Heterosis

杂种优势的监管破坏假说

• 批准号: 0924025
• 负责人: Luca Comai
• 金额: $ 49.94万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-15 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0924025&HistoricalAwards=false
• 关键词: Regulatory; Disruption; Hypothesis; Heterosis

PI: Luca Comai (University of California, Davis)CoPI: Vladimir Filkov (University of California, Davis)Heterosis defines the increased vigor displayed by hybrid progeny compared to the inbred parents. Its molecular basis is not understood, except that genetic differences between parents are the likely cause. This work addresses the following hypothesis: "Hybrids suffer regulatory impairment because the parental contribution to regulatory complexes is mismatched in structure or amount. Relaxed regulation results in activation of pathways that cause enhanced growth". To test this hypothesis, RNA abundance, allelic contribution, and chromatin state will be investigated using hybrids of rice. The objectives are to: (i) compare the effect of evolutionary distance on parents and hybrid expression differences and parental expression preference; (ii) correlate expression changes to promoter activity and changes in repressive chromatin state, and (iii) examine the effects of hybridity on regulatory networks to determine if genes associated with growth are targets of hybrid misregulation. This analysis will entail a novel technology called cDNA-RESCAN to distinguish parental expression contributions at an effective cost, and will employ a bioinformatic and computational team for dissection of regulatory hierarchies. By exploring a specific hypothesis of heterosis, this work will provide important information on the overall regulatory effect of hybridity. Because the biological system is rice, the best understood grass genome and globally, the most important food crop, the acquired knowledge is likely to impact both our basic understanding of cellular function and the molecular understanding of pathways that may affect yield in wheat, maize and other critical crops for the US economy. Educational components of this research will involve training of undergraduates from local and from under-represented communities. Data will be made available on the NIH GEO expression database, and the laboratory website (http://comailab.genomecenter.ucdavis.edu/).

主要研究者：Luca Comai（加州大学戴维斯分校）CoPI：弗拉基米尔Filkov（加州大学戴维斯分校）杂种优势定义了杂交后代与近交亲本相比表现出的活力增加。其分子基础尚不清楚，除了父母之间的遗传差异是可能的原因。这项工作解决了以下假设：“杂种遭受监管损害，因为父母的贡献，监管复合物是不匹配的结构或数量。放松调节导致激活导致增强生长的途径”。为了验证这一假设，RNA丰度，等位基因的贡献，和染色质状态将使用杂交水稻进行调查。其目标是：（i）比较进化距离对亲本和杂交体表达差异以及亲本表达偏好的影响;（ii）将表达变化与启动子活性和抑制性染色质状态的变化相关联;以及（iii）检查杂交性对调控网络的影响，以确定与生长相关的基因是否是杂交体误调控的靶。这项分析将需要一种名为cDNA-RESCAN的新技术，以有效的成本区分亲本表达的贡献，并将采用生物信息学和计算团队来解剖监管层次。通过探索杂种优势的一个特定假说，这项工作将提供重要信息的整体调控效应的杂交。由于生物系统是水稻，最了解的草基因组和全球最重要的粮食作物，所获得的知识可能会影响我们对细胞功能的基本理解以及对可能影响小麦，玉米和其他美国经济关键作物产量的途径的分子理解。这项研究的教育部分将涉及培训来自当地和代表性不足社区的本科生。 将在NIH GEO表达数据库和实验室网站（http：//comailab.genomecenter.ucdavis.edu/）上提供数据。