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Single-Molecule Specific Mislocalization of Red Fluorescent Proteins in Live Escherichia coli.

ABSTRACT: Tagging of individual proteins with genetically encoded fluorescent proteins (FPs) has been used extensively to study localization and interactions in live cells. Recent developments in single-molecule localization microscopy have enabled the dynamic visualization of individual tagged proteins inside living cells. However, tagging proteins with FPs is not without problems: formation of insoluble aggregates and inhibition of native functions of the protein are well-known issues. Previously reported artifacts manifest themselves at all expression levels of the FP-tagged proteins, making the design of control experiments relatively straightforward. Here, we describe a previously uncharacterized mislocalization artifact of Entacmaea quadricolor red fluorescent protein variants that is detectable at the single-molecule level in live Escherichia coli cells.

SUBMITTER: Ghodke H

PROVIDER: S-EPMC4944719 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Single-Molecule Specific Mislocalization of Red Fluorescent Proteins in Live Escherichia coli.

Ghodke Harshad H Caldas Victor E A VE Punter Christiaan M CM van Oijen Antoine M AM Robinson Andrew A

Biophysical journal 20160620 1

Tagging of individual proteins with genetically encoded fluorescent proteins (FPs) has been used extensively to study localization and interactions in live cells. Recent developments in single-molecule localization microscopy have enabled the dynamic visualization of individual tagged proteins inside living cells. However, tagging proteins with FPs is not without problems: formation of insoluble aggregates and inhibition of native functions of the protein are well-known issues. Previously report ...[more]

PMID: 27338860

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