Biophysical characterization of the structural change of Nopp140, an intrinsically disordered protein, in the interaction with CK2α
- Department of Chemistry, Kookmin University, Jeongneung-dong, Seongbuk-gu, Seoul 02707 (Korea, Republic of)
- Biomedical Research Institute, Korea Institute of Science and Technology, Seoul 02792 (Korea, Republic of)
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760 (Korea, Republic of)
- Division of Biosystems Research, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141 (Korea, Republic of)
Nucleolar phosphoprotein 140 (Nopp140) is a nucleolar protein, more than 80% of which is disordered. Previous studies have shown that the C-terminal region of Nopp140 (residues 568–596) interacts with protein kinase CK2α, and inhibits the catalytic activity of CK2. Although the region of Nopp140 responsible for the interaction with CK2α was identified, the structural features and the effect of this interaction on the structure of Nopp140 have not been defined due to the difficulty of structural characterization of disordered protein. In this study, the disordered feature of Nopp140 and the effect of CK2α on the structure of Nopp140 were examined using single-molecule fluorescence resonance energy transfer (smFRET) and electron paramagnetic resonance (EPR). The interaction with CK2α was increased conformational rigidity of the CK2α-interacting region of Nopp140 (Nopp140C), suggesting that the disordered and flexible conformation of Nopp140C became more rigid conformation as it binds to CK2α. In addition, site specific spin labeling and EPR analysis confirmed that the residues 574–589 of Nopp140 are critical for binding to CK2α. Similar technical approaches can be applied to analyze the conformational changes in other IDPs during their interactions with binding partners. - Highlights: • Nopp140 is intrinsically disordered protein (IDP). • Conformation of Nopp140 became more rigid conformation due to interaction with CK2α. • smFRET and EPR could be applied to analyze the structural changes of IDPs.
- OSTI ID:
- 22606154
- Journal Information:
- Biochemical and Biophysical Research Communications, Vol. 477, Issue 2; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0006-291X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Structure of an EIIC sugar transporter trapped in an inward-facing conformation
Thermodynamic contribution of backbone conformational entropy in the binding between SH3 domain and proline-rich motif