Ehrnsperger, Monika and Graber, Simone and Gaestel, Matthias and Buchner, Johannes (1997) Binding of non-native protein to Hsp25 during heat shock creates a reservoir of folding intermediates for reactivation. EMBO JOURNAL, 16 (2). pp. 221-229. ISSN 0261-4189, 1460-2075
Full text not available from this repository.Abstract
Small heat shock proteins (sHsps) are a conserved and ubiquitous protein family. Their ability to convey thermoresistance suggests their participation in protecting the native conformation of proteins. However, the underlying functional principles of their protective properties and their role in concert with other chaperone families remain enigmatic, Here, we analysed the influence of Hsp25 on the inactivation and subsequent aggregation of a model protein, citrate synthase (CS), under heat shock conditions in vitro. We show that stable binding of several non-native CS molecules to one Hsp25 oligomer leads to an accumulation of CS unfolding intermediates, which are protected from irreversible aggregation. Furthermore, a number of different proteins which bind to Hsp25 can he isolated from heat-shocked extracts of cells. Under permissive folding conditions, CS can be released from Hsp25 and, in cooperation with Hsp70, an ATP-dependent chaperone, the native state can be restored. Taken together, our findings allow us to integrate sHsps functionally in the cellular chaperone system operating under heat shock conditions. The task of sHsps in this context is to efficiently trap a large number of unfolding proteins in a folding-competent state and thus create a reservoir of non-native proteins for an extended period of time, allowing refolding after restoration of physiological conditions in cooperation with other chaperones.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | ALPHA-B-CRYSTALLIN; MAMMALIAN STRESS PROTEINS; EHRLICH ASCITES TUMOR; MOLECULAR CHAPERONES; CELLULAR THERMORESISTANCE; DROSOPHILA-MELANOGASTER; ACTIN POLYMERIZATION; ESCHERICHIA-COLI; PHOSPHORYLATION; EXPRESSION; chaperone; heat shock; Hsp 25; Hsp 70; protein folding |
| Subjects: | 500 Science > 540 Chemistry & allied sciences 500 Science > 570 Life sciences |
| Divisions: | Biology, Preclinical Medicine > Institut für Biophysik und physikalische Biochemie |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 17 May 2023 07:56 |
| Last Modified: | 17 May 2023 07:56 |
| URI: | https://pred.uni-regensburg.de/id/eprint/51097 |
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