A 12(S)-hydroxyeicosatetraenoic acid receptor interacts with steroid receptor coactivator-1
2000 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 97, no 11, 5779-5783 p.Article in journal (Refereed) Published
Lewis lung carcinoma cells contain specific high-affinity binding sites for the eicosanoid 12(S)-hydroxy-5,8,10,14-eicosatetraenoic acid [12(S)-HETE]. These binding sites have a cytosolic/nuclear localization and contain the heat shock proteins hsp70 and hsp90 as components of a high molecular weight cytosolic binding complex. The ligand binding subunit of this complex is a protein with an apparent molecular mass of ÿ50 kDa as judged by gel permeation chromatography. In this report, we present data showing that the 50-kDa 12(S)-HETE binding protein interacts as a homodimer with steroid receptor coactivator-1 (SRC-1) in the presence of 12(S)-HETE. Two putative interaction domains were mapped. One of these (amino acids 701-781) was within the nuclear receptor interaction domain in SRC-1 required for binding of various steroid and thyroid hormone receptors. It contains the most C-terminal of the three copies of LXXLL motif present in the nuclear receptor interaction domain. The second interaction domain was present in the N-terminal part of SRC-1 (amino acids 1-221). This region has two LXXLL motifs, one does not bind and the other binds only weakly to steroid and thyroid hormone receptors. Glutathione S-transferase (GST) pulldown experiments and far Western analyses demonstrated that the N-terminal region of SRC-1 (amino acids 1-212) alone does not bind the 50-kDa 12(S)-HETE binding protein, whereas GST/?SRC-11-1138 ligand-dependently pulled down a protein of ÿ50 kDa in size. Our results suggest that the 50-kDa 12(S)-HETE binding protein is a receptor that may signal through interaction with a nuclear receptor coactivator protein.
Place, publisher, year, edition, pages
National Academy of Sciences , 2000. Vol. 97, no 11, 5779-5783 p.
National CategoryMedical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-25055DOI: 10.1073/pnas.97.11.5779ISI: 000087318700022PubMedID: 10823935Local ID: 9483OAI: oai:DiVA.org:liu-25055DiVA: diva2:245381