title: Combinatorial targeting and discovery of ligand-receptors in organelles of mammalian cells.
abstract: Phage display screening allows the study of functional protein-protein interactions at the cell surface, but investigating intracellular organelles remains a challenge. Here we introduce internalizing-phage libraries to identify clones that enter mammalian cells through a receptor-independent mechanism and target-specific organelles as a tool to select ligand peptides and identify their intracellular receptors. We demonstrate that penetratin, an antennapedia-derived peptide, can be displayed on the phage envelope and mediate receptor-independent uptake of internalizing phage into cells. We also show that an internalizing-phage construct displaying an established mitochondria-specific localization signal targets mitochondria, and that an internalizing-phage random peptide library selects for peptide motifs that localize to different intracellular compartments. As a proof-of-concept, we demonstrate that one such peptide, if chemically fused to penetratin, is internalized receptor-independently, localizes to mitochondria, and promotes cell death. This combinatorial platform technology has potential applications in cell biology and drug development.
authors.affiliation: David H. Koch Center, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA.
authors.forename: Roberto
authors.initials: R
authors.lastname: Rangel
authors.forename: Liliana
authors.initials: L
authors.lastname: Guzman-Rojas
authors.forename: Lucia G
authors.initials: LG
authors.lastname: le Roux
authors.forename: Fernanda I
authors.initials: FI
authors.lastname: Staquicini
authors.forename: Hitomi
authors.initials: H
authors.lastname: Hosoya
authors.forename: E Magda
authors.initials: EM
authors.lastname: Barbu
authors.forename: Michael G
authors.initials: MG
authors.lastname: Ozawa
authors.forename: Jing
authors.initials: J
authors.lastname: Nie
authors.forename: Kenneth
authors.initials: K
authors.lastname: Dunner
authors.forename: Robert R
authors.initials: RR
authors.lastname: Langley
authors.forename: E Helene
authors.initials: EH
authors.lastname: Sage
authors.forename: Erkki
authors.initials: E
authors.lastname: Koivunen
authors.forename: Juri G
authors.initials: JG
authors.lastname: Gelovani
authors.forename: Roy R
authors.initials: RR
authors.lastname: Lobb
authors.forename: Richard L
authors.initials: RL
authors.lastname: Sidman
authors.forename: Renata
authors.initials: R
authors.lastname: Pasqualini
authors.forename: Wadih
authors.initials: W
authors.lastname: Arap
mesh_terms: D000595:Amino Acid Sequence; D001435:Bacteriophages / Q000235:genetics / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism / Q000821:virology; D057846:Cell-Penetrating Peptides; D015870:Gene Expression; D005821:Genetic Techniques; D006801:Humans; D008024:Ligands; D008969:Molecular Sequence Data; D015388:Organelles / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D057846:Cell-Penetrating Peptides; D008024:Ligands; D011956:Receptors, Cell Surface; C414409:penetratin