Journal
BIOCHEMISTRY
Volume 44, Issue 34, Pages 11389-11401Publisher
AMER CHEMICAL SOC
DOI: 10.1021/bi050483p
Keywords
-
Categories
Funding
- NHLBI NIH HHS [HL56712, HL079389] Funding Source: Medline
Ask authors/readers for more resources
The first intracellular loop (iLP1, residues 39-51) of human prostacyclin receptor (IP) was proposed to be involved in signaling via its interaction with the G alpha s protein. First, evidence of the IP iLP1 interaction with the C-terminus of the G alpha s protein was observed by the fluorescence and NMR spectroscopy using the synthetic peptide (G alpha s-Ct) mimicking the C-terminal I I residues of the G alpha s protein in the presence of a constrained synthetic peptide mimicking the IP iLP1. Then, the residues (Arg42, Ala44, and Arg45) in the IP iLP1 peptide possibly involved in contacting the G alpha s-Ct peptide were initially assigned by observation of the significant proton resonance shifts of the side chains of the constrained IP iLP1 peptide using 2D H-1 NMR spectroscopy. The results of the NMR studies were used as a guide for further identification of the residues in the IP important to the receptor signaling using a recombinant protein approach. A profile of the residues in the IP iLP1, including the residues observed from the NMR studies involved in the G alpha s mediated signaling, was mapped out by mutagenesis. According to our results, it can be predicted that the seven residues (Arg42-Ala48) with the conserved Arg45 at the center will form an epitope with a specific conformation involved in the G alpha s mediated signaling. The conservation of the basic residues (Arg45 in the IP) in all of the prostanoid receptors suggests that the iLP1 regions of the other prostanoid receptors may also contain the epitopes important to their signaling.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available