Journal article
A GPR-Protein Interaction Surface of Giα: Implications for the Mechanism of GDP-Release Inhibition
Biochemistry (Easton), Vol.41(1), pp.258-265
01/08/2002
DOI: 10.1021/bi015708k
PMID: 11772024
Abstract
Proteins containing G-protein regulatory (GPR) motifs represent a novel family of guanine nucleotide dissociation inhibitors (GDIs) for Gα subunits from the Gi family. They selectively interact with the GDP-bound conformation of Giα and transducin-α (Gtα), but not with Gsα. A series of chimeric proteins between Giα1 and Gsα has been constructed to investigate GPR-contact sites on Gα subunits and the mechanism of GPR-protein GDI activity. Analysis of the interaction of two GPR-proteinsAGS3GPR and Pcp2with the chimeric Gα subunits demonstrated that the GPR−Giα1 interface involves the Giα1 switch regions and Giα1-144−151, a site within the helical domain. Residues within Giα1-144−151 form conformation-sensitive contacts with switch III, and may directly interact with a GPR-protein or form a GPR-binding surface jointly with switch III. The helical domain site is critical to the ability of GPR-proteins to act as GDIs. Our data suggest that a mechanism of the GDI activity of GPR-proteins is different from that of GDIs for monomeric GTPases and from the GDI-like activity of Gβγ subunits. The GPR-proteins are likely to block a GDP-escape route on Gα subunits.
Details
- Title: Subtitle
- A GPR-Protein Interaction Surface of Giα: Implications for the Mechanism of GDP-Release Inhibition
- Creators
- Michael NatochinKarim G GasimovNikolai O Artemyev
- Resource Type
- Journal article
- Publication Details
- Biochemistry (Easton), Vol.41(1), pp.258-265
- Publisher
- American Chemical Society
- DOI
- 10.1021/bi015708k
- PMID
- 11772024
- ISSN
- 0006-2960
- eISSN
- 1520-4995
- Language
- English
- Date published
- 01/08/2002
- Academic Unit
- Molecular Physiology and Biophysics; Iowa Neuroscience Institute; Ophthalmology and Visual Sciences
- Record Identifier
- 9984025372502771
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