The Arabidopsis glutamyl-tRNA reductase (GluTR) forms a ternary complex with FLU and GluTR-binding protein.
The Arabidopsis glutamyl-tRNA reductase (GluTR) forms a ternary complex with FLU and GluTR-binding protein.
复制标题
拟南芥谷氨酰-tRNA 还原酶 (GluTR) 与 FLU 和 GluTR 结合蛋白形成三元复合物
DOI：
10.1038/srep19756
复制
发表时间：
2016-01-22
影响因子：
4.6
通讯作者：
Liu L
中科院分区：
文献类型：
--
作者：
Fang Y;Zhao S;Zhang F;Zhao A;Zhang W;Zhang M;Liu L
四氢吡咯的生物合成是一个重要且受到严格调控的过程，而谷氨酰-tRNA还原酶(GluTR)是翻译后水平上多种调控因子的关键靶点。通过与类囊体膜蛋白荧光蛋白(Flu)或可溶性基质GluTR结合蛋白(GBP)结合，GluTR的活性被下调或上调。在这里，我们重建了一个由Flu、GBP和GlutR的C-末端四肽重复结构域组成的三元络合物，结晶并在3.2kA的温度下求解了该络合物的结构。其整体结构类似于先前报道的两个合并的二元络合物的形状，并在GluTR内部显示了较大的构象变化。我们还证明在相同的条件下，GluTR与GBP结合紧密，但不与GSAM结合。这些发现使我们能够暗示三元复合体在调节植物Glutr方面的生物学作用。
Tetrapyrrole biosynthesis is an essential and tightly regulated process, and glutamyl-tRNA reductase (GluTR) is a key target for multiple regulatory factors at the post-translational level. By binding to the thylakoid membrane protein FLUORESCENT (FLU) or the soluble stromal GluTR-binding protein (GBP), the activity of GluTR is down- or up-regulated. Here, we reconstructed a ternary complex composed of the C-terminal tetratricopepetide-repeat domain of FLU, GBP, and GluTR, crystallized and solved the structure of the complex at 3.2 Å. The overall structure resembles the shape of merged two binary complexes as previously reported, and shows a large conformational change within GluTR. We also demonstrated that GluTR binds tightly with GBP but does not bind to GSAM under the same condition. These findings allow us to suggest a biological role of the ternary complex for the regulation of plant GluTR.