Analysis low level Hsp90 proteome by SILAC in yeast

ABSTRACT: Hsp90 is one of the most abundant and conserved proteins in the cell. Reduced levels or activity of Hsp90 causes defects in many cellular processes and also reveals genetic or non-genetic variation in populations. Despite information about Hsp90 protein-protein interactions, a global view of the Hsp90 regulated proteome in yeast is unavailable. To investigate the degree of dependency of individual yeast proteins on Hsp90, we used the SILAC method coupled with mass spectrometry (MS) to quantify around 4000 proteins in low-Hsp90 cells and observed that 904 proteins were changed in their abundance by more than 1.5 fold. When compared with the transcriptome of the same population of cells, two-thirds of the mis-regulated proteins were observed to be affected post-transcriptionally, of which the majority were down-regulated. Further analyses indicated that the down-regulated proteins are highly conserved and assume central roles in cellular networks with a high number of interacting partners, suggesting that Hsp90 buffers genetic or non-genetic variation through regulating protein network hubs. The down-regulated proteins were enriched for essential proteins previously unknown to be Hsp90-dependent. Finally, we observed that down-regulation of transcription factors and mating pathway components by attenuating Hsp90 function led to decreased target gene expression and pheromone response respectively, providing a direct link between observed proteome regulation and cellular phenotypes.

OTHER RELATED OMICS DATASETS IN: PRJNA242663

INSTRUMENT(S): LTQ Orbitrap Elite

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

TISSUE(S): Cell Culture

SUBMITTER: Scott Schuyler  

LAB HEAD: Scott C. Schuyler

PROVIDER: PXD001162 | Pride | 2014-10-24

REPOSITORIES: Pride