Abstract 486: Uncovering novel PERK signaling pathways through chemical-genetic screening

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA The ER kinase PERK, a key mediator of the Unfolded Protein Response, is known to promote tumorigenesis, cell migration, and metastasis, as well as inhibit anoikis. Though PERK has these and other important cellular functions, only a handful of its direct substrates are currently known. Therefore, in order to provide an expanded view of PERK function and further definition of its signaling networks, we have used a chemical-genetic approach to screen for additional PERK substrates. We find that a mutation in the PERK ATP binding pocket renders it sensitive to bulky ATP analogs both in vitro and in cells. Furthermore, bulky ATPγS analogs were used exclusively by the analog-sensitive version of PERK to label substrates with thiophosphate. After labeling, thiophosphopeptides were affinity purified by covalent capture and subsequently identified by tandem mass spectrometry. Utilization of this analog-sensitive PERK allele for substrate characterization will be discussed. Citation Format: Nancy L. Maas, Rebecca Levin, Nickpreet Singh, Kevan Shokat, J. Alan Diehl. Uncovering novel PERK signaling pathways through chemical-genetic screening. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 486. doi:10.1158/1538-7445.AM2014-486