title: mRNA display selection of an optimized MDM2-binding peptide that potently inhibits MDM2-p53 interaction.
abstract: p53 is a tumor suppressor protein that prevents tumorigenesis through cell cycle arrest or apoptosis of cells in response to cellular stress such as DNA damage. Because the oncoprotein MDM2 interacts with p53 and inhibits its activity, MDM2-p53 interaction has been a major target for the development of anticancer drugs. While previous studies have used phage display to identify peptides (such as DI) that inhibit the MDM2-p53 interaction, these peptides were not sufficiently optimized because the size of the phage-displayed random peptide libraries did not cover all of the possible sequences. In this study, we performed selection of MDM2-binding peptides from large random peptide libraries in two stages using mRNA display. We identified an optimal peptide named MIP that inhibited the MDM2-p53 and MDMX-p53 interactions 29- and 13-fold more effectively than DI, respectively. Expression of MIP fused to the thioredoxin scaffold protein in living cells by adenovirus caused stabilization of p53 through its interaction with MDM2, resulting in activation of the p53 pathway. Furthermore, expression of MIP also inhibited tumor cell proliferation in a p53-dependent manner more potently than DI. These results show that two-stage, mRNA-displayed peptide selection is useful for the rapid identification of potent peptides that target oncoproteins.
authors.affiliation: Department of Biosciences and Informatics, Keio University, Yokohama, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Shiheido
authors.forename: Hideaki
authors.initials: H
authors.lastname: Takashima
authors.forename: Nobuhide
authors.initials: N
authors.lastname: Doi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yanagawa
mesh_terms: D000256:Adenoviridae / Q000187:drug effects / Q000378:metabolism; D000595:Amino Acid Sequence; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004797:Enzyme-Linked Immunosorbent Assay; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D020128:Inhibitory Concentration 50; D008969:Molecular Sequence Data; D019151:Peptide Library; D010455:Peptides / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects; D051736:Proto-Oncogene Proteins c-mdm2 / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D016415:Sequence Alignment; D015398:Signal Transduction / Q000187:drug effects; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D019151:Peptide Library; D010455:Peptides; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D016159:Tumor Suppressor Protein p53; D049452:Green Fluorescent Proteins; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2