基于RNA-seq方法研究驯化牡丹适应性进化的分子机制

项目名称： 基于RNA-seq方法研究驯化牡丹适应性进化的分子机制

项目编号： No.31470328

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 生物科学

项目作者： 袁军辉

作者单位： 上海辰山植物园

项目金额： 85万元

中文摘要： 适应性和自然选择是进化生物学研究的核心领域。驯化是一个富有科学意义、人文内涵和应用价值的科学问题，驯化植物为人类提供了最主要的粮食和最基本的生存资料。在基因组水平深入研究植物驯化模式和机制，将揭示栽培植物适应性的分子机制，为品种改良和新品种培育提供理论基础。以重瓣花为主的中原牡丹和紫斑牡丹品种类型各自驯化起源于开单瓣花的野生矮牡丹（Paeonia jishanensis）和野生裂叶紫斑牡丹(P. rockii ssp. atava)，提供了一个非常理想的研究适应性平行进化机制的模式系统。本项目拟通过对栽培牡丹和其野生近亲（并选取两个外类群）的花芽分化和花发育多个关键时期的转录组进行测序(RNA-seq) ，解析在栽培牡丹驯化过程中受选择的基因及位点（正选择分析和差异表达基因分析），并分析渐渗杂交对栽培牡丹驯化的贡献，进而揭示驯化牡丹适应性进化的分子机制。

中文关键词： 适应性进化；驯化牡丹；正选择；差异表达基因；渐渗杂交

英文摘要： What are the genetic bases of adaptation remains a central question in evolutionary biology. Domesticated species represent excellent models for studying such adaptive processes because they been under strong and recent selection. Given its overwhelming importance in evolution, as a model system and as a key process in the rising of human civilizations, few processes deserve more attention in this endeavor than domestication. Furthermore, an understanding of the genomics of plant domestication can guide breeding programs that aim to improve cultivated species. Cultivated tree peonies (genus Paeonia L.) are among the most popular ornamental plants in the world; two independent domestication events have occurred from different wild species, leading to convergent phenotypes. The cultivated common and flare tree peonies independently domesticated from wild P. jishanensis and P. rockii ssp. atava. The cultivated peonies thus represent an interesting case of parallel and convergent evolution, which allows addressing the question of whether similar adaptations can occur in different ways or whether there is a single path for a given phenotype. We will integrate high-throughput sequencing and state-of-the-art inference methods to address a fundamental problem in biology and identify the genomic processes involved in adaptation, and convergence, using tree peonies as models. The proposed research should yield unprecedented insights into the genomics of adaptation. These include the genetic architecture of adaptation, as well as the genomic regions and processes involved. We will advance our understanding of the relative importance of amino-acid substitutions, gene regulation, introgressions and drift, as well as the proportion of the genome involved in domestication. The results will also have direct applied implications for guide breeding programs that aim to improve cultivated species.

英文关键词： Evolutionary adaptation;domesticated tree peonies;positive selection;changes in gene expression;introgression