%0 Journal Article
%T In Situ Evaluation of Estrogen Receptor Dimers in Breast Carcinoma Cells: Visualization of Protein-Protein Interactions
%A Erina Iwabuchi
%A Hironobu Sasano
%A Katsuhiko Ono
%A Yasuhiro Miki
%A Yoshiaki Onodera
%J Archive of "Acta Histochemica et Cytochemica".
%D 2017
%R 10.1267/ahc.17011
%X The estrogen receptor (ER) functions as a dimer and is involved in several different biological functions. However ER dimeric proteins have not been identified by in situ methodologies. Structured illumination microscopy (SIM) has been recently developed, which enabled the localization of protein and protein interaction. Therefore, in this study, we firstly demonstrated that ERs formed both homodimers and heterodimers in breast carcinoma cell lines using Nikon¡¯s SIM (N-SIM). ER¦Á/¦Á homodimers were detected in the nuclei of both ER¦Á-positive MCF-7 and T-47D cells; 23.0% and 13.4% of ER¦Á proteins formed ER¦Á/¦Á homodimers, respectively. ER¦Á/¦Â heterodimers were also detected in MCF-7 and T-47D. Approximately 6.6% of both ER¦Á and ER¦Â1 proteins formed ER¦Á/¦Â1 heterodimers in MCF-7. In addition, 18.1% and 22.4% of ER¦Á and ER¦Â proteins formed ER¦Á/¦Â2 heterodimers and ER¦Á/¦Â5 heterodimers in MCF-7, respectively. In addition, by using proximity ligation assay (PLA) in MCF-7, estradiol-induced ER¦Á/¦Á homodimers and ER¦Á/¦Â1 heterodimers were both detected after 15 to 45 min of treatment and at 15 min, respectively. The percentage of total ER proteins could also be determined using N-SIM. By using both methods, it has become possible to evaluate precise localization and ratio of ER dimers among different cell types
%K structured illumination microscopy
%K proximity ligation assay
%K estrogen receptor dimer
%K protein-protein interaction
%K breast cancer
%U https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5433938/