Direct inter-subdomain interactions switch between the closed and open forms of the Hsp70 nucleotide-binding domain in the nucleotide-free state
| Autor: | Mikako Shirouzu, Tetsuo Takagi, Akihiko Arakawa, Akiko Tanaka, S. Kishishita, Mutsuko Kukimoto-Niino, Sumio Sugano, Shigeyuki Yokoyama, Ryohei Ishii, Meiri Shida |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Models
Molecular BAG domain Binding Sites Nucleotides Chemistry Stereochemistry macromolecular substances General Medicine Crystallography X-Ray Protein Structure Tertiary Crystallography Protein structure Structural Biology Cyclic nucleotide-binding domain Helix Hydrolase Humans HSP70 Heat-Shock Proteins Protein folding Binding site Binding domain |
| Zdroj: | Acta Crystallographica Section D Biological Crystallography. 66:223-232 |
| ISSN: | 0907-4449 |
| DOI: | 10.1107/s0907444909053979 |
| Popis: | The 70 kDa heat-shock proteins (Hsp70s) are highly conserved chaperones that are involved in several cellular processes, such as protein folding, disaggregation and translocation. In this study, the crystal structures of the human Hsp70 nucleotide-binding domain (NBD) fragment were determined in the nucleotide-free state and in complex with adenosine 5′-(β,γ-imido)triphosphate (AMPPNP). The structure of the nucleotide-free NBD fragment is similar to that of the AMPPNP-bound NBD fragment and is designated as the `closed form'. In the nucleotide-free NBD fragment the closed form is intrinsically supported through interactions between Tyr15, Lys56 and Glu268 which connect subdomains IA, IB and IIB at the centre of the protein. Interaction with the substrate-binding domain (SBD) of Hsp70 or the BAG domain of BAG1 impairs this subdomain connection and triggers the rotation of subdomain IIA around a hydrophobic helix from subdomain IA. The subdomain rotation is limited by Asp199 and Asp206 from subdomain IIA and clearly defines the open form of the NBD. The open form is further stabilized by a new interaction between Gly230 from subdomain IIB and Ser340 from subdomain IIA. The structure of the NBD in the nucleotide-free state is determined by switching of the inter-subdomain interactions. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text