| Content Provider |
World Health Organization (WHO)-Global Index Medicus |
| Author |
Matsunami, Risë Ortíz, Víctor Ström, Anders López-barradas, Adriana M. Torres, Nimbe Ordaz-rosado, David García-becerra, Rocío Gustafsson, Jan-åke Engler, David A. Velázquez-villegas, Laura A. Larrea, Fernando Tovar, Armando R. |
| Description |
Author Affiliation: Velázquez-Villegas LA ( Posgrado en Ciencias Bioquímicas, Universidad Nacional Autónoma de México, 04510 México D.F., México); Ortíz V ( Departamento de Fisiología de la Nutrición, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, 14000 México D.F., México); Ström A ( Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX 77204); Torres N ( Departamento de Fisiología de la Nutrición, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, 14000 México D.F., México); Engler DA ( Proteomics Programmatic Core, Houston Methodist Hospital Research Institute, Houston, TX 77030); Matsunami R ( Proteomics Programmatic Core, Houston Methodist Hospital Research Institute, Houston, TX 77030); Ordaz-Rosado D ( Departamento de Biología de la Reproducción, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, 14000 México D.F., México); García-Becerra R ( Departamento de Biología de la Reproducción, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, 14000 México D.F., México); López-Barradas AM ( Departamento de Fisiología de la Nutrición, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, 14000 México D.F., México); Larrea F ( Departamento de Biología de la Reproducción, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, 14000 México D.F., México); Gustafsson JÅ ( Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX 77204); Tovar AR ( Departamento de Fisiología de la Nutrición, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, 14000 México D.F., México); |
| Abstract |
The sodium-coupled neutral amino acid transporter 2 (SNAT2) translocates small neutral amino acids into the mammary gland to promote cell proliferation during gestation. It is known that SNAT2 expression increases during pregnancy, and in vitro studies indicate that this transporter is induced by 17ß-estradiol. In this study, we elucidated the mechanism by which 17ß-estradiol regulates the transcription of SNAT2. In silico analysis revealed the presence of a potential estrogen response element (ERE) in the SNAT2 promoter. Reporter assays showed an increase in SNAT2 promoter activity when cotransfected with estrogen receptor alpha (ER- ) after 17ß-estradiol stimulation. Deletion of the ERE reduced estradiol-induced promoter activity by 63%. Additionally, EMSAs and supershift assays showed that ER- binds to the SNAT2 ERE and that this binding competes with the interaction of ER- with its consensus ERE. An in vivo ChIP assay demonstrated that the binding of ER- to the SNAT2 promoter gradually increased in the mammary gland during gestation and that maximal binding occurred at the highest 17ß-estradiol serum concentration. Liquid chromatography-elevated energy mass spectrometry and Western blot analysis revealed that the SNAT2 ER- -ERE complex contained poly(ADP-ribose) polymerase 1, Lupus Ku autoantigen protein p70, and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) proteins and that the silencing of each of these proteins nearly abolished 17ß-estradiol-stimulated SNAT2 promoter activity. Nuclear levels of GAPDH increased progressively during gestation in the mammary gland, and GAPDH binding was nucleotide-specific for the SNAT2 ERE. Thus, this study provides new insights into how the mammary epithelium adapts to control amino acid uptake through the transcriptional regulation of the SNAT2 transporter via 17ß-estradiol. |
| ISSN |
00278424 |
| e-ISSN |
10916490 |
| Journal |
Proceedings of the National Academy of Sciences of the United States of America |
| Issue Number |
31 |
| Volume Number |
111 |
| Language |
English |
| Publisher |
National Academy of Sciences |
| Publisher Date |
2014-08-01 |
| Publisher Place |
United States |
| Access Restriction |
Open |
| Subject Keyword |
Amino Acid Transport Systems Genetics Estradiol Pharmacology Gene Expression Regulation Drug Effects Transcription, Genetic Metabolism Animals Antigens, Nuclear Cell Nucleus DNA-Binding Proteins Epithelium Estrogen Receptor Alpha Glyceraldehyde-3-Phosphate Dehydrogenases HeLa Cells Mammary Glands, Animal Molecular Sequence Data Peptide Fragments Poly(ADP-ribose) Polymerases Pregnancy Protein Binding Response Elements Research Support, Non-U.S. Gov't Multidisciplinary |
| Content Type |
Text |
| Resource Type |
Article |
| Subject |
Multidisciplinary |
