期刊
JOURNAL OF BIOLOGICAL CHEMISTRY
卷 280, 期 29, 页码 27356-27365出版社
AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
DOI: 10.1074/jbc.M502814200
关键词
-
资金
- NIGMS NIH HHS [GM47426, GM29076, GM15977] Funding Source: Medline
The biological effects of the ISG15 protein arise in part from its conjugation to cellular targets as a primary response to interferon-alpha/beta induction and other markers of viral or parasitic infection. Recombinant full-length ISG15 has been produced for the first time in high yield by mutating Cys(78) to stabilize the protein and by cloning in a C-terminal arginine cap to protect the C terminus against proteolytic inactivation. The cap is subsequently removed with carboxypeptidase B to yield mature biologically active ISG15 capable of stoichiometric ATP-dependent thiolester formation with its human UbE1L activating enzyme. The three-dimensional structure of recombinant ISG15C78S was determined at 2.4-angstrom resolution. The ISG15 structure comprises two beta-grasp folds having main chain root mean square deviation (r. m. s. d.) values from ubiquitin of 1.7 angstrom (N-terminal) and 1.0 angstrom ( C-terminal). The beta-grasp domains pack across two conserved 310 helices to bury 627 angstrom(2) that accounts for 7% of the total solvent-accessible surface area. The distribution of ISG15 surface charge forms a ridge of negative charge extending nearly the full-length of the molecule. Additionally, the N-terminal domain contains an apolar region comprising almost half its solvent accessible surface. The C-terminal domain of ISG15 was superimposed on the structure of Nedd8 ( r. m. s. d. = 0.84 angstrom) bound to its AppBp1-Uba3 activating enzyme to model ISG15 binding to UbE1L. The docking model predicts several key side-chain interactions that presumably define the specificity between the ubiquitin and ISG15 ligation pathways to maintain functional integrity of their signaling.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据