| Autor: |
Kang H; Life Sciences Division, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650, Republic of Korea., Lee WK, Choi YH, Vukoti KM, Bang WG, Yu YG |
| Jazyk: |
angličtina |
| Zdroj: |
Biochemical and biophysical research communications [Biochem Biophys Res Commun] 2005 Apr 08; Vol. 329 (2), pp. 684-92. |
| DOI: |
10.1016/j.bbrc.2005.02.040 |
| Abstrakt: |
The serotonin type 6 (5-HT(6)) receptor is a G-protein coupled receptor (GPCR) coupled to a stimulatory G-protein (G(S)). To identify the structural basis for the interaction of the 5-HT(6) receptor with the G(S) protein, we have dissected the interaction between GST-fusion proteins containing the second intracellular loop (iL2), the third intracellular loop (iL3), or the C-terminal tail of the 5-HT(6) receptor and the alpha subunit of G(S) (Galpha(S)). The direct interaction of iL3 and Galpha(S) was demonstrated by co-immunoprecipitation. Furthermore, the kinetic parameters of the interaction between iL3 and Galpha(S) were measured by surface plasmon resonance, and the apparent dissociation constant was determined to be 0.9 x 10(-6)M. In contrast, the second intracellular loop and C-terminal tail regions showed negligible affinity to Galpha(S). The critical residues within the iL3 region for the interaction with Galpha(S) were identified as conserved positively charged residues near the C-terminus of iL3 by measuring the cellular levels of cAMP produced in response to 5-HT stimulation of cells transfected with 5-HT(6) receptor mutants. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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Full Text from ScienceDirect