title: Proteome-wide identification of family member-specific natural substrate repertoire of caspases.
abstract: Caspases are proteolytic enzymes that are essential for apoptosis. Understanding the many discrete and interacting signaling pathways mediated by caspases requires the identification of the natural substrate repertoire for each caspase of interest. Using an amplification-based protein selection technique called mRNA display, we developed a high-throughput screen platform for caspase family member specific substrates on a proteome-wide scale. A large number of both known and previously uncharacterized caspase-3 substrates were identified from the human proteome. The proteolytic features of these selected substrates, including their cleavage sites and specificities, were characterized. Substrates that were cleaved only by caspase-8 or granzyme B but not by caspase-3, were readily selected. The method can be widely applied for efficient and systematic identification of the family member specific natural substrate repertoire of any caspase in an organism of interest, in addition to that of numerous other proteases with high specificity.
authors.affiliation: School of Pharmacy and Carolina Center for Genome Sciences, University of North Carolina, Chapel Hill, NC 27599, USA.
authors.forename: Wujian
authors.initials: W
authors.lastname: Ju
authors.forename: C Alexander
authors.initials: CA
authors.lastname: Valencia
authors.forename: Hao
authors.initials: H
authors.lastname: Pang
authors.forename: Yan
authors.initials: Y
authors.lastname: Ke
authors.forename: Weiyi
authors.initials: W
authors.lastname: Gao
authors.forename: Biao
authors.initials: B
authors.lastname: Dong
authors.forename: Rihe
authors.initials: R
authors.lastname: Liu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002166:Camptothecin / Q000494:pharmacology; D020169:Caspases / Q000378:metabolism*; D002460:Cell Line; D006224:Cricetinae; D053804:Granzymes / Q000378:metabolism; D006801:Humans; D020543:Proteome / Q000145:classification / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D013379:Substrate Specificity
chemical_list: D020543:Proteome; D012333:RNA, Messenger; D053804:Granzymes; D020169:Caspases; D002166:Camptothecin