6FHK

Structure of a modified protein containing a genetically encoded phosphoserine

Summary for 6FHK

• Entry DOI: 10.2210/pdb6fhk/pdb
• Descriptor: Heat shock 70 kDa protein 1A, ADENOSINE-5'-DIPHOSPHATE, PHOSPHATE ION, ... (6 entities in total)
• Functional Keywords: chaperone, phosphoserine, adp
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 2
• Total formula weight: 85358.28

Authors

Mukherjee, M.,Bayliss, R. (deposition date: 2018-01-14, release date: 2018-10-24, Last modification date: 2024-01-17)

Primary citation

Mukherjee, M.,Sabir, S.,O'Regan, L.,Sampson, J.,Richards, M.W.,Huguenin-Dezot, N.,Ault, J.R.,Chin, J.W.,Zhuravleva, A.,Fry, A.M.,Bayliss, R.
Mitotic phosphorylation regulates Hsp72 spindle localization by uncoupling ATP binding from substrate release.
Sci Signal, 11:-, 2018

PubMed Abstract: Hsp72 is a member of the 70-kDa heat shock family of molecular chaperones (Hsp70s) that comprise a nucleotide-binding domain (NBD) and a substrate-binding domain (SBD) connected by a linker that couples the exchange of adenosine diphosphate (ADP) for adenosine triphosphate (ATP) with the release of the protein substrate. Mitotic phosphorylation of Hsp72 by the kinase NEK6 at Thr located in the NBD promotes the localization of Hsp72 to the mitotic spindle and is required for efficient spindle assembly and chromosome congression and segregation. We determined the crystal structure of the Hsp72 NBD containing a genetically encoded phosphoserine at position 66. This revealed structural changes that stabilized interactions between subdomains within the NBD. ATP binding to the NBD of unmodified Hsp72 resulted in the release of substrate from the SBD, but phosphorylated Hsp72 retained substrate in the presence of ATP. Mutations that prevented phosphorylation-dependent subdomain interactions restored the connection between ATP binding and substrate release. Thus, phosphorylation of Thr is a reversible mechanism that decouples the allosteric connection between nucleotide binding and substrate release, providing further insight into the regulation of the Hsp70 family. We propose that phosphorylation of Hsp72 on Thr by NEK6 during mitosis promotes its localization to the spindle by stabilizing its interactions with components of the mitotic spindle.

PubMed: 30108182
DOI: 10.1126/scisignal.aao2464

Experimental method

X-RAY DIFFRACTION (1.657 Å)