Genetic Variation and the Heritability of Epigenetic Responses to Temperature

摘要 基因组产生单个人类体内存在的多种细胞类型的能力， 或植物，是从进化到控制的特殊调控机制中衍生出来的 核苷酸到蛋白质的转录和翻译。类似的机制也一直存在 允许有机体通过塑料方式改变发育，以响应外部环境 环境条件。环境调节的发展轨迹的转变通常是 通过化学和物理操作基因组的表观遗传修饰， 进而改变基因的表达。而基因调控的变化则是由于 转录级联通常是转瞬即逝的，表观遗传修饰可以跨细胞持续存在 分裂，在某些情况下是世代之间的分裂。对进化和健康的影响 表观遗传仍然知之甚少，尤其是知识匮乏。 关于遗传变异如何改变对环境的表观遗传反应。我提议 利用快速的生命周期、巨大的表型可塑性、基因组资源和自花授粉 多花含羞草植物模型系统研究植物间相互作用的能力 遗传变异和表观遗传。我假设当地的适应驱动着 调节环境诱导的基因和调控区域的差异 表观遗传，继而产生跨代基因的自然变异 表达和表型可塑性。我将通过以下目标来检验这一假设： 一、评估遗传变异、跨代遗传和 环境条件对基因表达、DNA甲基化、 和发展。 二、确定跨代遗传自然变异的遗传基础 温度状态。 三、衡量跨代遗传和“跨代x遗传”的作用 不同田间条件对植物存活和发育的影响。

Abstract The capability of a genome to produce the diversity of cell types present within a single human, or plant, is derived from the extraordinary regulatory mechanisms that have evolved to control the transcription and translation of nucleotide to protein. Similar mechanisms have also been coopted to allow organisms to plastically alter development in response to external environmental conditions. Environmentally mediated shifts in developmental trajectory are often mediated by epigenetic modifications that chemically and physically manipulate the genome, and in turn alter the expression of genes. While changes in gene regulation due to transcriptional cascades are often fleeting, epigenetic modifications can persist across cell divisions, and in some cases between generations. The evolutionary and health ramifications of epigenetic inheritance are still quite poorly understood, with a particular dearth of knowledge regarding how genetic variation alters epigenetic responses to the environment. I propose to leverage the rapid life cycle, vast phenotypic plasticity, genomic resources, and self-fertilizing capability of the Mimulus laciniatus plant model system to study the interactions between genetic variation and epigenetic inheritance. I hypothesize that local adaptation drives divergence in the genes and regulatory regions that mediate environmentally induced epigenetic inheritance, in turn generating natural variation in transgenerational gene expression and phenotypic plasticity. I will test this hypothesis with the following aims: I. Assess the contribution of genetic variation, transgenerational inheritance, and environmental conditions on the regulation of gene expression, DNA methylation, and development. II. Determine the genetic basis of natural variation for transgenerational inheritance to temperature regimes. III. Measure the role of transgenerational inheritance and “transgenerational x genetic” effects on plant survival and development in divergent field conditions.