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Semisynthetic fluorescent pH sensors for imaging exocytosis and endocytosis.

ABSTRACT: The GFP-based superecliptic pHluorin (SEP) enables detection of exocytosis and endocytosis, but its performance has not been duplicated in red fluorescent protein scaffolds. Here we describe "semisynthetic" pH-sensitive protein conjugates with organic fluorophores, carbofluorescein, and Virginia Orange that match the properties of SEP. Conjugation to genetically encoded self-labeling tags or antibodies allows visualization of both exocytosis and endocytosis, constituting new bright sensors for these key steps of synaptic transmission.

SUBMITTER: Martineau M

PROVIDER: S-EPMC5680258 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Semisynthetic fluorescent pH sensors for imaging exocytosis and endocytosis.

Martineau Magalie M Somasundaram Agila A Grimm Jonathan B JB Gruber Todd D TD Choquet Daniel D Taraska Justin W JW Lavis Luke D LD Perrais David D

Nature communications 20171110 1

The GFP-based superecliptic pHluorin (SEP) enables detection of exocytosis and endocytosis, but its performance has not been duplicated in red fluorescent protein scaffolds. Here we describe "semisynthetic" pH-sensitive protein conjugates with organic fluorophores, carbofluorescein, and Virginia Orange that match the properties of SEP. Conjugation to genetically encoded self-labeling tags or antibodies allows visualization of both exocytosis and endocytosis, constituting new bright sensors for t ...[more]

PMID: 29123102

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