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Capturing protein communities by structural proteomics in a thermophilic eukaryote

ABSTRACT: The arrangement of proteins into complexes is a key organizational principle for many cellular functions. Although the topology of many complexes has been systematically analyzed in isolation, their molecular sociology in situ remains elusive. Here, we show that crude cellular extracts of a eukaryotic thermophile, Chaetomium thermophilum, retain basic principles of cellular organization. Using a structural proteomics approach, we simultaneously characterized the abundance, interactions and structure of a third of the C. thermophilum proteome within these extracts. We identified 27 distinct protein communities that include 108 interconnected complexes, which dynamically associate with each other and functionally benefit from being in close proximity in the cell. Furthermore, we investigated the structure of fatty acid synthase within these extracts by cryoEM and this revealed multiple, flexible states of the enzyme in adaptation to its association with other complexes, thus exemplifying the need for in situ studies. As the components of the captured protein communities are known – at both the protein and complex level – this study constitutes another step forward towards a molecular understanding ofsubcellular organization.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Chaetomium Thermophilum (strain Dsm 1495 / Cbs 144.50 / Imi 039719)

SUBMITTER: Francis O'Reilly

LAB HEAD: Juri Rappsilber

PROVIDER: PXD006626 | Pride | 2017-07-26

REPOSITORIES: Pride

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			Action	DRS
	10FDR_ChaetomiumTotalCrosslinks_Links_xiFDR1.0.12.32.csv	Csv
	Chaetomium_ProtSEC_frac3-6_pepSEC12.zip	Other
	Cheatomium_ProtSEC_frac11-14_pepSEC11.raw	Raw
	Cheatomium_ProtSEC_frac11-14_pepSEC11.zip	Other
	Cheatomium_ProtSEC_frac11-14_pepSEC12.raw	Raw

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Capturing protein communities by structural proteomics in a thermophilic eukaryote

Project description:The arrangement of proteins into complexes is a key organizational principle for many cellular functions. Although the topology of many complexes has been systematically analyzed in isolation, their molecular sociology in situ remains elusive. Here, we show that crude cellular extracts of a eukaryotic thermophile, Chaetomium thermophilum, retain basic principles of cellular organization. Using a structural proteomics approach, we simultaneously characterized the abundance, interactions and structure of a third of the C. thermophilum proteome within these extracts. We identified 27 distinct protein communities that include 108 interconnected complexes, which dynamically associate with each other and functionally benefit from being in close proximity in the cell.

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