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A protein-tagging system for signal amplification in gene expression and fluorescence imaging.

ABSTRACT: Signals in many biological processes can be amplified by recruiting multiple copies of regulatory proteins to a site of action. Harnessing this principle, we have developed a protein scaffold, a repeating peptide array termed SunTag, which can recruit multiple copies of an antibody-fusion protein. We show that the SunTag can recruit up to 24 copies of GFP, thereby enabling long-term imaging of single protein molecules in living cells. We also use the SunTag to create a potent synthetic transcription factor by recruiting multiple copies of a transcriptional activation domain to a nuclease-deficient CRISPR/Cas9 protein and demonstrate strong activation of endogenous gene expression and re-engineered cell behavior with this system. Thus, the SunTag provides a versatile platform for multimerizing proteins on a target protein scaffold and is likely to have many applications in imaging and controlling biological outputs.

SUBMITTER: Tanenbaum ME

PROVIDER: S-EPMC4252608 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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A protein-tagging system for signal amplification in gene expression and fluorescence imaging.

Tanenbaum Marvin E ME Gilbert Luke A LA Qi Lei S LS Weissman Jonathan S JS Vale Ronald D RD

Cell 20141009 3

Signals in many biological processes can be amplified by recruiting multiple copies of regulatory proteins to a site of action. Harnessing this principle, we have developed a protein scaffold, a repeating peptide array termed SunTag, which can recruit multiple copies of an antibody-fusion protein. We show that the SunTag can recruit up to 24 copies of GFP, thereby enabling long-term imaging of single protein molecules in living cells. We also use the SunTag to create a potent synthetic transcrip ...[more]

PMID: 25307933

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