Abscisic acid is required for somatic embryo initiation through mediating spatial auxin response in Arabidopsis
Abscisic acid is required for somatic embryo initiation through mediating spatial auxin response in Arabidopsis
复制标题
在拟南芥中，脱落酸通过介导空间生长素反应来启动体细胞胚胎
DOI：
10.1007/s10725-012-9759-2
复制
发表时间：
2013-03-01
影响因子：
4.2
通讯作者：
Zhang, Xian Sheng
中科院分区：
文献类型：
--
作者：
Su, Ying Hua;Su, Yu Xiao;Zhang, Xian Sheng
脱落酸（阿坝）调节植物发育的许多方面，包括体细胞胚（SE）的启动。然而，阿坝对SE启动的作用机制仍有待研究。在本研究中，我们研究了拟南芥愈伤组织在SE诱导过程中内源阿坝含量的变化。我们进一步发现，SE启动的能力受到强烈损害的处理fluridone，阿坝生物合成的有效抑制剂，以及阿坝生物合成基因ABA2的突变，这表明阿坝是必需的SE启动。此外，氟啶酮处理抑制了胚性愈伤组织中生长素的合成和极性运输，导致生长素反应模式紊乱，降低了胚性愈伤组织的再生频率。然而，在培养基中施加外源阿坝几乎恢复了生长素反应和SE启动的模式。由此可见，阿坝通过介导生长素的合成和极性运输来建立愈伤组织中生长素的反应模式，从而对SE的发生起作用。我们的研究为理解SE的启动机制提供了新的信息。
Abscisic acid (ABA) regulates many aspects of plant development, including somatic embryo (SE) initiation. However, mechanisms of ABA functions on SE initiation have remained to be investigated. In this study, we examined the endogenous ABA contents of calli in Arabidopsis during the SE inductive process. We further found that the capacity for SE initiation was strongly impaired by treatment of fluridone, a potent inhibitor of ABA biosynthesis, as well as by mutation of ABA biosynthetic gene ABA2, suggesting that ABA is required for SE initiation. Furthermore, treatment of fluridone inhibited local auxin biosynthesis and auxin polar transport in the embryonic calli, resulting in the disturbance of auxin response pattern and the decreased regeneration frequency of SEs. However, application of exogenous ABA in the medium almost recovered patterns of auxin response and SE initiation. Thus, the results suggest that ABA functions on SE initiation through mediating both auxin biosynthesis and polar transport for establishment of auxin response pattern in callus. Our study provides new information for understanding mechanisms of SE initiation.