title: C-terminal amino acids are essential for human heat shock protein 70 dimerization.
abstract: The human inducible heat shock protein 70 (hHsp70), which is involved in several major pathologies, including neurodegenerative disorders and cancer, is a key molecular chaperone and contributes to the proper protein folding and maintenance of a large number of protein structures. Despite its role in disease, the current structural knowledge of hHsp70 is almost exclusively based on its Escherichia coli homolog, DnaK, even though these two proteins only share ~50 % amino acid identity. For the first time, we describe a complete heterologous production and purification strategy that allowed us to obtain a large amount of soluble, full-length, and non-tagged hHsp70. The protein displayed both an ATPase and a refolding activity when combined to the human Hsp40. Multi-angle light scattering and bio-layer interferometry analyses demonstrated the ability of hHsp70 to homodimerize. The role of the C-terminal part of hHsp70 was identified and confirmed by a study of a truncated version of hHsp70 that could neither dimerize nor present refolding activity.
authors.affiliation: INSERM, UMR 866, 7 blvd Jeanne d'Arc, 21000, Dijon, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Marcion
authors.forename: Renaud
authors.initials: R
authors.lastname: Seigneuric
authors.forename: Evelyne
authors.initials: E
authors.lastname: Chavanne
authors.forename: Yves
authors.initials: Y
authors.lastname: Artur
authors.forename: Loïc
authors.initials: L
authors.lastname: Briand
authors.forename: Tarik
authors.initials: T
authors.lastname: Hadi
authors.forename: Jessica
authors.initials: J
authors.lastname: Gobbo
authors.forename: Carmen
authors.initials: C
authors.lastname: Garrido
authors.forename: Fabrice
authors.initials: F
authors.lastname: Neiers
mesh_terms: D002942:Circular Dichroism; D019281:Dimerization; D004926:Escherichia coli / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007526:Isoelectric Point; D058849:Protein Refolding; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000302:isolation & purification; D013050:Spectrometry, Fluorescence
chemical_list: D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D011994:Recombinant Proteins; C063842:dnaK protein, E coli