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Detection of Isoforms Differing by a Single Charge Unit in Individual Cells.

ABSTRACT: To measure protein isoforms in individual mammalian cells, we report single-cell resolution isoelectric focusing (scIEF) and high-selectivity immunoprobing. Microfluidic design and photoactivatable materials establish the tunable pH gradients required by IEF and precisely control the transport and handling of each 17-pL cell lysate during analysis. The scIEF assay resolves protein isoforms with resolution down to a single-charge unit, including both endogenous cytoplasmic and nuclear proteins from individual mammalian cells.

SUBMITTER: Tentori AM

PROVIDER: S-EPMC5201312 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Detection of Isoforms Differing by a Single Charge Unit in Individual Cells.

Tentori Augusto M AM Yamauchi Kevin A KA Herr Amy E AE

Angewandte Chemie (International ed. in English) 20160906 40

To measure protein isoforms in individual mammalian cells, we report single-cell resolution isoelectric focusing (scIEF) and high-selectivity immunoprobing. Microfluidic design and photoactivatable materials establish the tunable pH gradients required by IEF and precisely control the transport and handling of each 17-pL cell lysate during analysis. The scIEF assay resolves protein isoforms with resolution down to a single-charge unit, including both endogenous cytoplasmic and nuclear proteins fr ...[more]

PMID: 27595864

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