20 de dezembro - terça-feira, 10 h.
Miniauditório do IQ
"Chaperoning the proteome: From network mapping to biochemical and biophysical studies".
Dr. Walid A. Houry, Department of Biochemistry, University of Toronto, Toronto, Canada; Department of Chemistry, University of Toronto, Toronto, Canada.
Abstract: Molecular chaperones are critical to maintaining cellular protein homeostasis. To obtain a comprehensive view of molecular chaperone function in the cell, we developed an integrative approach based on systematic physical and genetic interaction mapping to decipher interactions involving all main chaperones (67) and cochaperones (15) of Saccharomyces cerevisiae. This work provided a new view of the cellular chaperone network. The network obtained clearly shows the distinction between chaperones having broad versus narrow substrate specificities. Our analysis revealed the presence of a large chaperone functional complex containing Hsp90, Hsp70, Hsp40, CCT and small Hsps among others. We name this complex the NAJ chaperone supercomplex. We unexpectedly found that many interactors of chaperones are proteins that form foci under stress conditions. Such foci-forming tendency was then demonstrated for the highly conserved AAA+ ATPases Rvb1 and Rvb2, which are part of the R2TP complex that also interacts with Hsp90. We propose that foci formation might be a feature of many chaperone interactors. Our progress in chaperone network mapping and follow up biochemical studies will be presented.
Docente responsável: Carlos H. I. Ramos