Lotus japonicus E3 Ligase SEVEN IN ABSENTIA4 Destabilizes the Symbiosis Receptor-Like Kinase SYMRK and Negatively Regulates Rhizobial Infection
Lotus japonicus E3 Ligase SEVEN IN ABSENTIA4 Destabilizes the Symbiosis Receptor-Like Kinase SYMRK and Negatively Regulates Rhizobial Infection
复制标题
DOI：
10.1105/tpc.110.082248
复制
发表时间：
2012-04-01
期刊：
影响因子：
11.6
通讯作者：
Parniske, Martin
中科院分区：
文献类型：
--
作者：
Den Herder, Griet;Yoshida, Satoko;Parniske, Martin
莲属植物共生受体样激酶（SYMRK）是微生物信号分子刺激根细胞后进行共生信号转导所必需的。在这里，我们确定了SYMRK相互作用的七缺席（SINA）E3泛素连接酶家族的成员，并证实了其预测的泛素连接酶活性。在本氏烟草叶片中，SYMRK-黄色荧光蛋白定位在质膜上，并与SINA相互作用，通过双分子荧光互补测定，观察到在质膜的胞质界面的小斑点。此外，荧光标记的SINA 4与SYMRK部分共定位，并导致SYMRK重新定位以及SYMRK从质膜上消失。无论是本地化，也不是丰富的Nod因子受体1的存在下，SINA 4的改变。在根共生过程中，SINA 4的转录上调，并且异位表达SINA 4的根瘤菌接种根显示SYMRK蛋白水平降低。按照负调控作用的共生，感染线程发展受损后，异位表达的SINA 4。我们的研究结果暗示SINA 4 E3泛素连接酶在营业额SYMRK，并提供了一个概念性的机制，其共生适当的时空遏制。
The Lotus japonicus SYMBIOSIS RECEPTOR-LIKE KINASE (SYMRK) is required for symbiotic signal transduction upon stimulation of root cells by microbial signaling molecules. Here, we identified members of the SEVEN IN ABSENTIA (SINA) E3 ubiquitin-ligase family as SYMRK interactors and confirmed their predicted ubiquitin-ligase activity. In Nicotiana benthamiana leaves, SYMRK-yellow fluorescent protein was localized at the plasma membrane, and interaction with SINAs, as determined by bimolecular fluorescence complementation, was observed in small punctae at the cytosolic interface of the plasma membrane. Moreover, fluorescence-tagged SINA4 partially colocalized with SYMRK and caused SYMRK relocalization as well as disappearance of SYMRK from the plasma membrane. Neither the localization nor the abundance of Nod-factor receptor1 was altered by the presence of SINA4. SINA4 was transcriptionally upregulated during root symbiosis, and rhizobia inoculated roots ectopically expressing SINA4 showed reduced SYMRK protein levels. In accordance with a negative regulatory role in symbiosis, infection thread development was impaired upon ectopic expression of SINA4. Our results implicate SINA4 E3 ubiquitin ligase in the turnover of SYMRK and provide a conceptual mechanism for its symbiosis-appropriate spatio-temporal containment.