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Structure and Interactions of the TPR Domain of Sgt2 with Yeast Chaperones and Ybr137wp.

ABSTRACT: Small glutamine-rich tetratricopeptide repeat-containing protein 2 (Sgt2) is a multi-module co-chaperone involved in several protein quality control pathways. The TPR domain of Sgt2 and several other proteins, including SGTA, Hop, and CHIP, is a highly conserved motif known to form transient complexes with molecular chaperones such as Hsp70 and Hsp90. In this work, we present the first high resolution crystal structures of Sgt2_TPR alone and in complex with a C-terminal peptide PTVEEVD from heat shock protein, Ssa1. Using nuclear magnetic resonance spectroscopy and isothermal titration calorimetry, we demonstrate that Sgt2_TPR interacts with peptides corresponding to the C-termini of Ssa1, Hsc82, and Ybr137wp with similar binding modes and affinities.

SUBMITTER: Krysztofinska EM

PROVIDER: S-EPMC5641545 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Structure and Interactions of the TPR Domain of Sgt2 with Yeast Chaperones and Ybr137wp.

Krysztofinska Ewelina M EM Evans Nicola J NJ Thapaliya Arjun A Murray James W JW Morgan Rhodri M L RML Martinez-Lumbreras Santiago S Isaacson Rivka L RL

Frontiers in molecular biosciences 20171011

Small glutamine-rich tetratricopeptide repeat-containing protein 2 (Sgt2) is a multi-module co-chaperone involved in several protein quality control pathways. The TPR domain of Sgt2 and several other proteins, including SGTA, Hop, and CHIP, is a highly conserved motif known to form transient complexes with molecular chaperones such as Hsp70 and Hsp90. In this work, we present the first high resolution crystal structures of Sgt2_TPR alone and in complex with a C-terminal peptide PTVEEVD from heat ...[more]

PMID: 29075633

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