%0 Journal Article
%T Chaperones contribute to G protein coupled receptor oligomerization, but do not participate in assembly of the G protein with the receptor signaling complex
%A Maha M Hammad
%A Denis J Dupr¨¦
%J Journal of Molecular Signaling
%D 2010
%I Ubiquity Press
%R 10.1186/1750-2187-5-16
%X Our goal is to understand the process whereby the adrenergic and angiotensin receptors attain their proper mature conformation. We determined whether any of the common chaperones are physically associated with the fully and/or immature ¦Â2AR and AT1R receptors forms and if they play any role in the selective recruitment of G proteins subunits to receptor complexes. Our results suggest that when a pair of receptors is expressed in such way that one is retained in the endoplasmic reticulum (ER), this immature receptor will dictate the chaperones interacting with the receptor complex. We showed that ERp57 is important for receptor dimerization of AT1R homo and ¦Â2AR/AT1R receptor dimers, but plays no role in the ¦Â2AR homodimerization. Then, we verified if some of those chaperones could play a role in the assembly of the heterotrimeric G protein subunits with the receptor complex, but none appeared to be essential.Overall, our results suggest that variations among receptor oligomers occur early in the synthesis/maturation processes, and that chaperones will interact more specifically with some receptor pairs than others to allow the formation of certain receptor pairs, while others will contribute to the folding and maturation of receptors without any effect on receptor assembly within a signaling complex.Seven transmembrane receptors (7TM-Rs) are the largest family of plasma membrane receptors and couple to G proteins to activate downstream signaling pathways that give rise to alterations in cell function and gene expression [1]. These receptors had traditionally been thought to exist as monomers, but it is now known that 7TM-Rs exist as homo- and heterooligomers [2,3]. Heteromerization of receptors is an exciting new field in pharmacology. It is possible that drugs that act on one receptor in a heteromer might influence the signal transduction mechanisms activated by the other receptor. AT1R undergoes homo- and heterodimerize with many other receptors, including bradyki
%U http://www.jmolecularsignaling.com/content/5/1/16