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Crystal structure of human ERp44 shows a dynamic functional modulation by its carboxy-terminal tail.

ABSTRACT: ERp44 mediates thiol-dependent retention in the early secretory pathway, forming mixed disulphides with substrate proteins through its conserved CRFS motif. Here, we present its crystal structure at a resolution of 2.6 A. Three thioredoxin domains-a, b and b'-are arranged in a clover-like structure. A flexible carboxy-terminal tail turns back to the b' and a domains, shielding a hydrophobic pocket in domain b' and a hydrophobic patch around the CRFS motif in domain a. Mutational and functional studies indicate that the C-terminal tail gates the CRFS area and the adjacent hydrophobic pocket, dynamically regulating protein quality control.

SUBMITTER: Wang L

PROVIDER: S-EPMC2475331 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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Crystal structure of human ERp44 shows a dynamic functional modulation by its carboxy-terminal tail.

Wang Likun L Wang Lei L Vavassori Stefano S Li Shengjian S Ke Huimin H Anelli Tiziana T Degano Massimo M Ronzoni Riccardo R Sitia Roberto R Sun Fei F Wang Chih-Chen CC

EMBO reports 20080613 7

ERp44 mediates thiol-dependent retention in the early secretory pathway, forming mixed disulphides with substrate proteins through its conserved CRFS motif. Here, we present its crystal structure at a resolution of 2.6 A. Three thioredoxin domains-a, b and b'-are arranged in a clover-like structure. A flexible carboxy-terminal tail turns back to the b' and a domains, shielding a hydrophobic pocket in domain b' and a hydrophobic patch around the CRFS motif in domain a. Mutational and functional s ...[more]

PMID: 18552768

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