건국대학교

CV(PDF)

이메일

댓글 1
Unique Unfoldase/Aggregase Activity of a Molecular Chaperone Hsp33 in its Holding-Inactive State
펼치기 Authors and Affiliations
Abstract

The various chaperone activities of heat shock proteins contribute to ensuring cellular proteostasis. Here, we demonstrate the non-canonical unfoldase activity as an inherent functionality of the prokaryotic molecular chaperone, Hsp33. Hsp33 was originally identified as a holding chaperone that is post-translationally activated by oxidation. However, in this study, we verified that the holding-inactive reduced form of Hsp33 (RHsp33) strongly bound to the translational elongation factor, EF-Tu. This interaction was critically mediated by the redox-switch domain of RHsp33 and the guanine nucleotide-binding domain of EF-Tu. The bound RHsp33, without undergoing any conformational change, catalyzed the EF-Tu aggregation by evoking the aberrant folding of EF-Tu to expose hydrophobic surfaces. Consequently, the oligomers/aggregates of EF-Tu, but not its functional monomeric form, were highly susceptible to proteolytic degradation by Lon protease. These findings present a unique example of an ATP-independent molecular chaperone with distinctive dual functions—as an unfoldase/aggregase and as a holding chaperone—depending on the redox status. It is also suggested that the unusual unfoldase/aggregase activity of RHsp33 can contribute to cellular proteostasis by dysregulating EF-Tu under heat-stressed conditions.

Abbreviations
ANS, 8-anilino-1-naphthalene sulfonic acid; CD, circular dichroism; D2, domain-II; D3, domain-III; DTT, dithiothreitol; EDTA, ethylenediaminetetraacetic acid; EF-Ts, elongation factor thermal-stable; EF-Tu, elongation factor thermal-unstable; GD, guanidine nucleotide-binding domain; Hsp33, heat shock protein 33; ITC, isothermal titration calorimetry; MLD, middle linker domain; RSD, redox-switch domain; TROSY, transverse relaxation optimized spectroscopy

Keywords : proteostasis; protein quality control; protein turnover; protein misfolding; protein aggregation

주소복사
논문정보   F1000선정
- 형식: Research article
- 게재일: 2019년 03월 (BRIC 등록일 2019-09-20)
- 연구진: 국내연구진태극기
- 분야: Biochemistry, Molecular_Biology
- 추천: Faculty of 1000 Biology
- 추천사유: Collet J and Goemans C: F1000Prime Recommendation of [Jo KS et al., J Mol Biol 2019 431(7):1468-1480]. In F1000Prime, 18 Sep 2019; 10.3410/f.735222321.793565263
댓글 (1)
김진23  |  2019.10.02 04:26     
교수님!!!
내일 회사 가서 자랑 해도 될까요? ㅎㅎ
진심으로 축하드립니다~!!
웨비나 참석자 모집중...
HOME   |   이용약관   |   개인정보처리방침
© BRIC