U1A RNA-binding domain at 1.8 A resolution.
U1A RNA-binding domain at 1.8 A resolution.
复制标题
U1A RNA 结合域，分辨率为 1.8 A。
DOI：
10.1107/s0907444903011338
复制
发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Ferré-D'Amaré,AdrianR
中科院分区：
文献类型：
--
作者：
Rupert,PeterB;Xiao,Hong;Ferré-D'Amaré,AdrianR
人类U1A rna结合域（RBD1）采用最常见的蛋白质折叠之一，即rna识别基序，是理解rna -蛋白质相互作用的范例。先前已经确定了未结合RBD1的2.8 Å分辨率结构[Nagai等人（1990）]。Nature (London), 348, 515-520]，并发现了一个定义良好的α/β核心，其末端无序。使用更长的结构，确定了1.8 Å分辨率的非结合结构域结构，揭示了有序的c端螺旋。这种螺旋的存在与自由域的解结构一致[Avis et al.(1996)]。[j] .中华生物医学工程学报，2004,26 (2):487 - 498；然而，在溶液结构中，螺旋遮挡了rna结合表面。在目前的结构中，螺旋的位置类似于1.9 Å分辨率RNA-RBD1复合物结构[Oubridge et al.(1994)]。自然（伦敦），372,432-438 [j]。本研究中的晶体是从2.2 M丙二酸钠中生长出来的。高盐浓度可能通过加强c末端螺旋的埋藏面与蛋白质的α/β核之间的疏水相互作用，帮助c末端螺旋在rna结合构象中定向。另外，丙二酸盐（其几个分子结合在RNA结合表面附近）可以模拟RNA。
The human U1A RNA-binding domain (RBD1) adopts one of the most common protein folds, the RNA-recognition motif, and is a paradigm for understanding RNA–protein interactions. A 2.8 Å resolution structure of the unbound RBD1 has previously been determined [Nagai et al. (1990). Nature (London), 348, 515–520] and revealed a well defined α/β core with disordered termini. Using a longer construct, a 1.8 Å resolution structure of the unbound domain was determined that reveals an ordered C-terminal helix. The presence of this helix is consistent with a solution structure of the free domain [Avis et al. (1996). J. Mol. Biol. 257, 398–411]; however, in the solution structure the helix occludes the RNA-binding surface. In the present structure, the helix occupies a position similar to that seen in a 1.9 Å resolution RNA–RBD1 complex structure [Oubridge et al. (1994). Nature (London), 372, 432–438]. The crystals in this study were grown from 2.2 M sodium malonate. It is possible that the high salt concentration helps to orient the C-terminal helix in the RNA-bound conformation by strengthening hydrophobic interactions between the buried face of the helix and the α/β core of the protein. Alternatively, the malonate (several molecules of which are bound in the vicinity of the RNA-binding surface) may mimic RNA.