Léon-Kloosterziel K M, van de Bunt G A, Zeevaart J A, Koornneef M
Department of Genetics, Wageningen Agricultural University, The Netherlands.
Plant Physiol. 1996 Jan;110(1):233-40. doi: 10.1104/pp.110.1.233.
The development of seed dormancy is an aspect of seed maturation, the last stage of seed development. To isolate mutants of Arabidopsis thaliana that are affected in this process, we selected directly for the absence of dormancy among freshly harvested M2 seeds. The screen yielded two mutants exhibiting a reduced dormancy, rdo1 and rdo2, that are specifically affected in dormancy determined by the embryo. The rdo1 and rdo2 mutants show normal levels of abscisic acid and the same sensitivity to abscisic acid, ethylene, auxin, and cytokinin as the wild type. The rdo2 mutant but not the rdo1 mutant has a reduced sensitivity to the gibberellin biosynthesis inhibitor tetcyclacis. Double-mutant analysis suggested that the RDO1 and RDO2 genes are involved in separate pathways leading to the development of dormancy. We assume that the RDO2 gene controls a step in the induction of dormancy that is most likely induced by abscisic acid and is expressed as an increase of the gibberellin requirement for germination.
种子休眠的形成是种子成熟（种子发育的最后阶段）的一个方面。为了分离出在此过程中受到影响的拟南芥突变体，我们直接在刚收获的M2种子中筛选无休眠的种子。该筛选产生了两个休眠降低的突变体rdo1和rdo2，它们在由胚决定的休眠方面受到特异性影响。rdo1和rdo2突变体的脱落酸水平正常，并且对脱落酸、乙烯、生长素和细胞分裂素的敏感性与野生型相同。rdo2突变体而非rdo1突变体对赤霉素生物合成抑制剂四环菌酸的敏感性降低。双突变分析表明，RDO1和RDO2基因参与导致休眠形成的不同途径。我们推测，RDO2基因控制休眠诱导中的一个步骤，该步骤很可能由脱落酸诱导，并表现为萌发所需赤霉素的增加。
