Crystal structure of human eIF3k, the first structure of eIF3 subunits
Crystal structure of human eIF3k, the first structure of eIF3 subunits
复制标题
DOI：
10.1074/jbc.m405158200
复制
发表时间：
2004-08-13
影响因子：
4.8
通讯作者：
Gong, WM
中科院分区：
文献类型：
--
作者：
Wei, ZY;Zhang, P;Gong, WM
eIF3k是真核生物起始因子3（eIF3）的最小亚基，与eIF3的其他几个亚基和40 S核糖体亚基相互作用。eIF3k在高等真核生物中是保守的，包括哺乳动物、昆虫和植物，并且其在人体组织中普遍表达。有趣的是，eIF3k并不存在于某些种类的酵母中。因此，eIF3k可能在高等生物中发挥独特的调节作用。在这里，我们报告了人类eIF3k的晶体结构，这是eIF3组分的第一个高分辨率结构。这种新的结构包含两个不同的结构域，一个HEAT（命名为亨廷顿，延伸因子3，蛋白磷酸酶2A的A亚基，雷帕霉素的靶标）重复样HAM（HEAT类似基序）结构域和一个翼状螺旋样WH结构域。通过结构比较和序列保守性分析，我们发现eIF3k具有三个假定的蛋白结合表面，并具有潜在的RNA结合活性。该结构为理解eIF3复合物的结构和功能提供了关键信息。
eIF3k, the smallest subunit of eukaryotic initiation factor 3 (eIF3), interacts with several other subunits of eIF3 and the 40 S ribosomal subunit. eIF3k is conserved among high eukaryotes, including mammals, insects, and plants, and it is ubiquitously expressed in human tissues. Interestingly, eIF3k does not exist in some species of yeast. Thus, eIF3k may play a unique regulatory role in higher organisms. Here we report the crystal structure of human eIF3k, the first high-resolution structure of an eIF3 component. This novel structure contains two distinct domains, a HEAT ( named for Huntington, elongation factor 3, A subunit of protein phosphatase 2A, target of rapamycin) repeat-like HAM ( HEAT analogous motif) domain and a winged-helix-like WH domain. Through structural comparison and sequence conservation analysis, we show that eIF3k has three putative protein-binding surfaces and has potential RNA binding activity. The structure provides key information for understanding the structure and function of the eIF3 complex.