Type I Hsp40s/DnaJs aggregates exhibit features reminiscent of amyloidogenic structures

Author(s)

Tiroli-Cepeda, Ana O. ; Linhares, Leonardo A. ; Aragao, Annelize Z. B. ; de Jesus, Jemmyson R. ; Wasilewska-Sampaio, Ana P. ; De Felice, Fernanda G. ; Ferreira, Sergio T. ; Borges, Julio C. ; Cyr, Douglas M. ; Ramos, Carlos H. I.

• Document type: Journal article
• Source: FEBS Journal; v. 291, n. 17, p. 20-pg., 2024-07-08.

Abstract

A rise in temperature triggers a structural change in the human Type I 40 kDa heat shock protein (Hsp40/DnaJ), known as DNAJA1. This change leads to a less compact structure, characterized by an increased presence of solvent-exposed hydrophobic patches and beta-sheet-rich regions. This transformation is validated by circular dichroism, thioflavin T binding, and Bis-ANS assays. The formation of this beta-sheet-rich conformation, which is amplified in the absence of zinc, leads to protein aggregation. This aggregation is induced not only by high temperatures but also by low ionic strength and high protein concentration. The aggregated conformation exhibits characteristics of an amyloidogenic structure, including a distinctive X-ray diffraction pattern, seeding competence (which stimulates the formation of amyloid-like aggregates), cytotoxicity, resistance to SDS, and fibril formation. Interestingly, the yeast Type I Ydj1 also tends to adopt a similar beta-sheet-rich structure under comparable conditions, whereas Type II Hsp40s, whether human or from yeast, do not. Moreover, Ydj1 aggregates were found to be cytotoxic. Studies using DNAJA1- and Ydj1-deleted mutants suggest that the zinc-finger region plays a crucial role in amyloid formation. Our discovery of amyloid aggregation in a C-terminal deletion mutant of DNAJA1, which resembles a spliced homolog expressed in the testis, implies that Type I Hsp40 co-chaperones may generate amyloidogenic species in vivo. (AU)

• FAPESP's process: 18/00768-0 - Correlation between metals and protein homeostasis: initial studies investigating the incorporation of the 68Zn isotope into the Hsp40 co-chaperone and its effect on yeast
• Grantee: Jemmyson Romário de Jesus
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/26131-5 - The chaperome: study of the relationship of the structure of its components and the maintenance of proteostasis
• Grantee: Carlos Henrique Inacio Ramos
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 17/11986-5 - Generation and storage of New Energy: bringing technological development for the country
• Grantee: Ana Flávia Nogueira
• Support Opportunities: Research Grants - Research Centers in Engineering Program
• FAPESP's process: 12/50161-8 - Study of the structure and function of the Hsp90 chaperone with emphasis on its role in cellular homeostasis
• Grantee: Carlos Henrique Inacio Ramos
• Support Opportunities: Research Projects - Thematic Grants