Colocalization of Estrogen Receptors with the Fluorescent Tamoxifen Derivative, FLTX1, Analyzed by Confocal Microscopy

  • Araceli Morales
  • Raquel Marín
  • Jorge Marrero-Alonso
  • Alicia Boto
  • Mario Díaz
Part of the Methods in Molecular Biology book series (MIMB, volume 1366)


Tamoxifen is a selective estrogen receptor modulator that competitively binds the ligand-binding domain of estrogen receptors. Binding of tamoxifen displaces its cognate ligand, 17β-estradiol, thereby hampering the activation of estrogen receptors. Cellular labeling of ER is typically carried out using specific antibodies which require permeabilization of cells, incubation with secondary antibodies, and are expensive and time consuming. In this article, we describe the usefulness of FLTX1, a novel fluorescent tamoxifen derivative, which allows the labeling of estrogen receptors in immunocytochemistry and immunohistochemistry studies, both under permeabilized and non-permeabilized conditions. Further, besides labeling canonical estrogen receptors, this novel fluorescent probe is also suitable for the identification of unconventional targets such membrane estrogen receptors as well as other noncanonical targets, some of which are likely responsible for the number of undesired side effects reported during long-term tamoxifen treatments.

Key words

Estrogenreceptors Fluorescent tamoxifen derivative Confocal microscopy FLTX1 Membrane estrogen receptors Intracellular estrogen receptors 



This work has been supported by grants SAF2010-22114-C02-01/02 (MD & RM), SAF2014-61644-EXP (MD)and SAF-2013-48399-R (AB) from Ministerio de Economía y Competitividad (Spain)


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Araceli Morales
    • 1
  • Raquel Marín
    • 2
    • 3
  • Jorge Marrero-Alonso
    • 4
  • Alicia Boto
    • 5
    • 6
  • Mario Díaz
    • 7
    • 8
  1. 1.Department of Physiology, Institute of Biomedical Technologies (ITB)Centre for Biomedical Research of the Canary Islands (CIBICAN), University of La LagunaTenerifeSpain
  2. 2.Departamento de FisiologíaFacultad de Medicina, University of La LagunaTenerifeSpain
  3. 3.Unidad asociada ULL-CSIC “Fisiología y biofísica de la membrana celular en patologías neurodegenerativas y tumoralesTenerifeSpain
  4. 4.Department of Animal BiologyUniversity of La LagunaTenerifeSpain
  5. 5.Instituto de Productos Naturales (IPNA, CSIC)TenerifeSpain
  6. 6.Unidad asociada ULL-CSIC “Fisiología y biofísica de la membrana celular en patologías neurodegenerativas y tumorales”TenerifeSpain
  7. 7.Laboratorio de Fisiología y Biofísica de MembranasDepartamento de Biología Animal, Facultad de Biología, University of La LagunaTenerifeSpain
  8. 8.Unidad asociada ULL-CSIC “Fisiología y biofísica de la membrana celular en patologías neurodegenerativas y tumorales”TenerifeSpain

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