title: mMAPS: a flow-proteometric technique to analyze protein-protein interactions in individual signaling complexes.
abstract: Signal transduction is a dynamic process that regulates cellular functions through multiple types of biomolecular interactions, such as the interactions between proteins and between proteins and nucleic acids. However, the techniques currently available for identifying protein-protein or protein-nucleic acid complexes typically provide information about the overall population of signaling complexes in a sample instead of information about the individual signaling complexes therein. We developed a technique called "microchannel for multiparameter analysis of proteins in a single complex" (mMAPS) that simultaneously detected individual target proteins either singly or in a multicomponent complex in cell or tissue lysates. We detected the target proteins labeled with fluorophores by flow proteometry, which provided quantified data in the form of multidimensional fluorescence plots. Using mMAPS, we quantified individual complexes of epidermal growth factor (EGF) with its receptor EGFR, EGFR with signal transducer and activator of transcription 3 (STAT3), and STAT3 with the acetylase p300 and DNA in lysates from cultured cells with and without treatment with EGF, as well as in lysates from tumor xenograft tissue. Consistent with the ability of this method to reveal the dynamics of signaling protein interactions, we observed that cells treated with EGF induced the interaction of EGF with EGFR and the autophosphorylation of EGFR, but this interaction decreased with longer treatment time. Thus, we expect that this technique may reveal new aspects of molecular interaction dynamics.
authors.affiliation: 1Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
authors.forename: Chao-Kai
authors.initials: CK
authors.lastname: Chou
authors.forename: Heng-Huan
authors.initials: HH
authors.lastname: Lee
authors.forename: Pei-Hsiang
authors.initials: PH
authors.lastname: Tsou
authors.forename: Chun-Te
authors.initials: CT
authors.lastname: Chen
authors.forename: Jung-Mao
authors.initials: JM
authors.lastname: Hsu
authors.forename: Hirohito
authors.initials: H
authors.lastname: Yamaguchi
authors.forename: Ying-Nai
authors.initials: YN
authors.lastname: Wang
authors.forename: Hong-Jen
authors.initials: HJ
authors.lastname: Lee
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Hsu
authors.forename: Jin-Fong
authors.initials: JF
authors.lastname: Lee
authors.forename: Jun
authors.initials: J
authors.lastname: Kameoka
authors.forename: Mien-Chie
authors.initials: MC
authors.lastname: Hung
mesh_terms: D019411:Clinical Laboratory Techniques / Q000379:methods*; D004815:Epidermal Growth Factor / Q000378:metabolism; D066246:ErbB Receptors / Q000378:metabolism; D005453:Fluorescence; D046912:Multiprotein Complexes / Q000032:analysis* / Q000502:physiology; D060066:Protein Interaction Maps / Q000502:physiology*; D040901:Proteomics / Q000379:methods*; D050796:STAT3 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D046912:Multiprotein Complexes; D050796:STAT3 Transcription Factor; D004815:Epidermal Growth Factor; D066246:ErbB Receptors