Dataset Information

Discovery Proteomics Identifies a Molecular Link between the Coatomer Protein Complex I and Androgen Receptor-dependent Transcription

ABSTRACT: Aberrant activation of androgen receptor (AR)-dependent transcriptional programs is a hallmark of human prostate cancers. At the molecular level, ligand-mediated AR activation is coordinated through spatial and temporal protein-protein interactions (PPIs) involving AR-interacting proteins, which we designate the “AR-interactome”. Despite many years of research, the ligand-sensitive protein complexes involved in ligand-mediated AR activation in prostate-tumor cells has not been clearly defined. Here, we describe the development, characterization, and utilization of a novel human LNCaP prostate-tumor cell line, N-AR, which stably expresses wild-type AR containing the streptavidin-binding peptide epitope tagged at its N-terminus (SBP-AR). A bioanalytical workflow involving streptavidin-chromatography and label-free quantitative mass spectrometry was used to identify SBP-AR and associated ligand-sensitive proteins/protein complexes functionally linked to AR activation in the cytosol of N-AR cells. Functional studies verified that ligand-sensitive streptavidin-copurified proteins encoded modulators of AR-mediated transcription, suggesting that these novel proteins were putative SBP-AR-interacting proteins in N-AR cells. This was supported by biochemical associations between recombinant SBP-AR and the ligand-sensitive COPI retrograde trafficking complex in vitro. Extensive biochemical and molecular experiments showed that the COPI-retrograde complex regulates ligand-mediated AR transcriptional activation through the mobilization of Golgi-localized ARA160 coactivator into the nuclear compartment of prostate-tumor cells. Collectively, this study provides a bioanalytical strategy to validate the AR-interactome and define novel AR-interacting proteins involved in ligand-mediated AR activation in prostate-tumor cells. Moreover, we describe a cellular system to study how compartment-specific AR-interacting proteins influence AR activation and contribute to aberrant AR-dependent transcription that underlies the majority of human prostate cancers.

INSTRUMENT(S): 6520 Quadrupole Time-of-Flight LC/MS

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Jordy Hsiao

LAB HEAD: Michael Eugene Wright

PROVIDER: PXD002861 | Pride | 2016-07-20

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	dirMS_041712_NAR_120mM_minus.d.zip	Other
	dirMS_041712_NAR_120mM_minus.pep.xml	Pepxml
	dirMS_041712_NAR_120mM_plus.d.zip	Other
	dirMS_041712_NAR_120mM_plus.pep.xml	Pepxml
	dirMS_041712_NAR_20mM_minus.pep.xml	Pepxml

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Discovery Proteomics Identifies a Molecular Link between the Coatomer Protein Complex I and Androgen Receptor-dependent Transcription.

Hsiao Jordy J JJ Smits Melinda M MM Ng Brandon H BH Lee Jinhee J Wright Michael E ME

The Journal of biological chemistry 20160630 36

Aberrant androgen receptor (AR)-dependent transcription is a hallmark of human prostate cancers. At the molecular level, ligand-mediated AR activation is coordinated through spatial and temporal protein-protein interactions involving AR-interacting proteins, which we designate the "AR-interactome." Despite many years of research, the ligand-sensitive protein complexes involved in ligand-mediated AR activation in prostate tumor cells have not been clearly defined. Here, we describe the developmen ...[more]

PMID: 27365400

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