Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA.
Mol Ecol. 2011 Aug;20(16):3336-49. doi: 10.1111/j.1365-294X.2011.05181.x. Epub 2011 Jul 8.
Seasonal germination timing of Arabidopsis thaliana strongly influences overall life history expression and is the target of intense natural selection. This seasonal germination timing depends strongly on the interaction between genetics and seasonal environments both before and after seed dispersal. DELAY OF GERMINATION 1 (DOG1) is the first gene that has been identified to be associated with natural variation in primary dormancy in A. thaliana. Here, we report interaccession variation in DOG1 expression and document that DOG1 expression is associated with seed-maturation temperature effects on germination; DOG1 expression increased when seeds were matured at low temperature, and this increased expression was associated with increased dormancy of those seeds. Variation in DOG1 expression suggests a geographical structure such that southern accessions, which are more dormant, tend to initiate DOG1 expression earlier during seed maturation and achieved higher expression levels at the end of silique development than did northern accessions. Although elimination of the synthesis of phytohormone abscisic acid (ABA) results in the elimination of maternal temperature effects on dormancy, DOG1 expression predicted dormancy better than expression of genes involved in ABA metabolism.
拟南芥的季节性萌发时间强烈影响其整体生活史表达，是自然选择的强烈目标。这种季节性萌发时间强烈依赖于遗传和种子散布前后的季节性环境之间的相互作用。延迟萌发 1（DOG1）是第一个被确定与拟南芥初级休眠的自然变异相关的基因。在这里，我们报告了 DOG1 表达的种间变异，并记录了 DOG1 表达与种子成熟温度对萌发的影响有关；当种子在低温下成熟时，DOG1 的表达增加，而这种增加的表达与这些种子休眠的增加有关。DOG1 表达的变异表明存在地理结构，即休眠程度较高的南部种在种子成熟过程中较早开始 DOG1 表达，并在蒴果发育结束时达到比北部种更高的表达水平。尽管消除植物激素脱落酸（ABA）的合成会消除母本温度对休眠的影响，但 DOG1 表达比参与 ABA 代谢的基因表达更能预测休眠。
