Blatch Gregory Lloyd, Edkins Adrienne Lesley
The Vice Chancellery, The University of Notre Dame Australia, Fremantle, Australia.
Biomedical Biotechnology Research Unit (BioBRU), Department of Biochemistry, Microbiology and Bioinformatics, Rhodes University, Makhanda, South Africa.
FEBS J. 2025 Jul;292(14):3629-3633. doi: 10.1111/febs.70108. Epub 2025 Apr 21.
Sti1/Hop is a cochaperone that regulates Hsp70 and Hsp90 chaperones. Sti1/Hop function is perceived as limited to scaffolding chaperone complexes, although recent studies suggest a broader function. Rutledge et al. show that while Sti1/Hop functions within chaperone complexes under basal conditions, during high stress, it operates independently to sequester soluble misfolded protein in the cytoplasm, a function typically associated with chaperones rather than cochaperones. Furthermore, the localisation and levels of Sti1/Hop are finely tuned to ensure orderly sequestration and resolution of misfolded proteins. These data support a role for Sti1/Hop as a cochaperone specialised for stressed proteostasis networks.
Sti1/Hop是一种辅助伴侣蛋白,可调节Hsp70和Hsp90伴侣蛋白。尽管最近的研究表明其功能更为广泛,但Sti1/Hop的功能通常被认为仅限于搭建伴侣蛋白复合物。拉特利奇等人表明,虽然在基础条件下Sti1/Hop在伴侣蛋白复合物中发挥作用,但在高应激状态下,它会独立运作,在细胞质中隔离可溶性错误折叠蛋白,这一功能通常与伴侣蛋白而非辅助伴侣蛋白相关。此外,Sti1/Hop的定位和水平经过精细调节,以确保错误折叠蛋白的有序隔离和解决。这些数据支持了Sti1/Hop作为一种专门用于应激蛋白稳态网络的辅助伴侣蛋白的作用。