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Multiplexed quantitation of protein expression and phosphorylation based on functionalized soluble nanopolymers.

ABSTRACT: We report here for the first time the multiplexed quantitation of phosphorylation and protein expression based on a functionalized soluble nanopolymer. The soluble nanopolymer, pIMAGO, is functionalized with Ti (IV) ions for chelating phosphoproteins in high specificity and with infrared fluorescent tags for direct, multiplexed assays. The nanopolymer allows for direct competition for epitopes on proteins of interest, thus facilitating simultaneous detection of phosphorylation by pIMAGO and total protein amount by protein antibody in the same well of microplates. The new strategy has a great potential to measure cell signaling events by clearly distinguishing actual phosphorylation signals from protein expression changes, thus providing a powerful tool to accurately profile cellular signal transduction in healthy and disease cells. We anticipate broad applications of this new strategy in monitoring cellular signaling pathways and discovering new signaling events.

SUBMITTER: Pan L

PROVIDER: S-EPMC3500620 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Multiplexed quantitation of protein expression and phosphorylation based on functionalized soluble nanopolymers.

Pan Li L Iliuk Anton A Yu Shuai S Geahlen Robert L RL Tao W Andy WA

Journal of the American Chemical Society 20121024 44

We report here for the first time the multiplexed quantitation of phosphorylation and protein expression based on a functionalized soluble nanopolymer. The soluble nanopolymer, pIMAGO, is functionalized with Ti (IV) ions for chelating phosphoproteins in high specificity and with infrared fluorescent tags for direct, multiplexed assays. The nanopolymer allows for direct competition for epitopes on proteins of interest, thus facilitating simultaneous detection of phosphorylation by pIMAGO and tota ...[more]

PMID: 23088311

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Dataset Information

Multiplexed quantitation of protein expression and phosphorylation based on functionalized soluble nanopolymers.

Publications

Multiplexed quantitation of protein expression and phosphorylation based on functionalized soluble nanopolymers.

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