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Fluorogenic probe for constitutive cellular endocytosis.

ABSTRACT: Endocytosis is a fundamental process of eukaryotic cells that is critical for nutrient uptake, signal transduction, and growth. We have developed a molecular probe to quantify endocytosis. The probe is a lipid conjugated to a fluorophore that is masked with an enzyme-activatable moiety known as the trimethyl lock. The probe is not fluorescent when incorporated into the plasma membrane of human cells but becomes fluorescent upon internalization into endosomes, where cellular esterases activate the trimethyl lock. Using this probe, we found that human breast cancer cells undergo constitutive endocytosis more rapidly than do matched noncancerous cells. These data reveal a possible phenotypic distinction of cancer cells that could be the basis for chemotherapeutic intervention.

SUBMITTER: Levine MN

PROVIDER: S-EPMC3671891 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Fluorogenic probe for constitutive cellular endocytosis.

Levine Michael N MN Hoang Trish T TT Raines Ronald T RT

Chemistry & biology 20130401 4

Endocytosis is a fundamental process of eukaryotic cells that is critical for nutrient uptake, signal transduction, and growth. We have developed a molecular probe to quantify endocytosis. The probe is a lipid conjugated to a fluorophore that is masked with an enzyme-activatable moiety known as the trimethyl lock. The probe is not fluorescent when incorporated into the plasma membrane of human cells but becomes fluorescent upon internalization into endosomes, where cellular esterases activate th ...[more]

PMID: 23601650

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