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Affinity purification probes of potential use to investigate the endogenous Hsp70 interactome in cancer.

ABSTRACT: Heat shock protein 70 (Hsp70) is a family of proteins with key roles in regulating malignancy. Cancer cells rely on Hsp70 to inhibit apoptosis, regulate senescence and autophagy, and maintain the stability of numerous onco-proteins. Despite these important biological functions in cancer, robust chemical tools that enable the analysis of the Hsp70-regulated proteome in a tumor-by-tumor manner are yet unavailable. Here we take advantage of a recently reported Hsp70 ligand to design and develop an affinity purification chemical toolset for potential use in the investigation of the endogenous Hsp70-interacting proteome in cancer. We demonstrate that these tools lock Hsp70 in complex with onco-client proteins and effectively isolate Hsp70 complexes for identification through biochemical techniques. Using these tools we provide proof-of-concept analyses that glimpse into the complex roles played by Hsp70 in maintaining a multitude of cell-specific malignancy-driving proteins.

SUBMITTER: Rodina A

PROVIDER: S-EPMC4134716 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Affinity purification probes of potential use to investigate the endogenous Hsp70 interactome in cancer.

Rodina Anna A Taldone Tony T Kang Yanlong Y Patel Pallav D PD Koren John J Yan Pengrong P DaGama Gomes Erica M EM Yang Chenghua C Patel Maulik R MR Shrestha Liza L Ochiana Stefan O SO Santarossa Cristina C Maharaj Ronnie R Gozman Alexander A Cox Marc B MB Erdjument-Bromage Hediye H Hendrickson Ronald C RC Cerchietti Leandro L Melnick Ari A Guzman Monica L ML Chiosis Gabriela G

ACS chemical biology 20140617 8

Heat shock protein 70 (Hsp70) is a family of proteins with key roles in regulating malignancy. Cancer cells rely on Hsp70 to inhibit apoptosis, regulate senescence and autophagy, and maintain the stability of numerous onco-proteins. Despite these important biological functions in cancer, robust chemical tools that enable the analysis of the Hsp70-regulated proteome in a tumor-by-tumor manner are yet unavailable. Here we take advantage of a recently reported Hsp70 ligand to design and develop an ...[more]

PMID: 24934503

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Affinity purification probes of potential use to investigate the endogenous Hsp70 interactome in cancer.

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Affinity purification probes of potential use to investigate the endogenous Hsp70 interactome in cancer.

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