玉米种子老化的表观遗传机制研究

项目名称： 玉米种子老化的表观遗传机制研究

项目编号： No.31200231

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 微生物学、植物学

项目作者： 赵欣欣

作者单位： 吉林农业大学

项目金额： 25万元

中文摘要： 目前在我国种子面临两个问题，一是农业生产的良种大量积压；二是农作种质资源以种子作为遗传载体的长期保存。延缓种子衰老、揭示种子老化机制是解决问题的主要途径。种子的衰老和劣变过程伴随着染色体畸变和分子水平的遗传变异。大量研究表明，真核生物的表观遗传修饰极易因细胞内在胁迫（如自由基累积）和外在环境（如各种生物和非生物胁迫）的变化而改变。因此，理论上种子的衰老和劣变过程可能有表观遗传机制的参与。本项目拟选用已筛选出的玉米杂交种及自交系为材料，对老化种子所发生的DNA 甲基化变异现象进行深入、系统的研究，探讨不同老化程度的种子之间、种子的不同解剖构造间、老化种子所萌发的幼苗间的DNA甲基化的遗传差异性，以期探究种子衰老与分子表观遗传机制的相关性。这对生产用种和种质资源的保存具有积极的意义，且对优良品种发挥其优势具有重要的作用。

中文关键词： 玉米；种子；老化；表观遗传；活力

英文摘要： At present two major issues are associated with crop seeds in our country, one is seed overstocking for the agricultural production, the second is the long-term seed preservation of germplasm resources as genetic carriers. Delaying the seed aging and revealing the seed aging mechanism are the main ways to solve the problems. Several studies have shown that seed aging and deterioration produce chromosome aberrations and molecular genetic variations. On the other hand, numerous studies have established that epigenetic modifications in eukaryotes are prone to alterations under both intrinsic cellular stresss (such as accumulation of free-radicals) and external environmental stresses (such as various kinds of biological and abiotic stresses). Therefore, in theory, the process of seed aging and deterioration may have epigenetic consequences. In this project, maize hybrids and inbred lines will be used as materials to investigate possible changes in DNA methylation (a prominent epigenetic marker) associated with the process of seed aging and deterioration. A major goal of this project is to try to answer the question of whether epigeneitc instability underly seed aging and deterioration, and if so, contracting measures might be conceived to avoide this outcome.

英文关键词： maize；seed；aging；epigenetic；vitality