COMPOSITIONS AND METHODS FOR INHIBITING G PROTEIN SIGNALING
The present invention relates to methods for identifying agents which bind to specific amino acid residues of the protein interaction site of G protein β protein subunit. Compounds identified in accordance with the assay of the invention and methods for using the compound for modulating at least one activity of a G protein are also provide.
1 . A method for identifying an agent that modulates at least one activity of a G protein comprising contacting a G protein β subunit with a test agent and determining whether the agent interacts with at least one amino acid residue of the protein interaction site of the β subunit thereby identifying an agent that modulates at least one activity of the G protein.
2 . An agent identified by the method of claim 1 .
3 . A method for identifying an agent that binds at least one amino acid residue of the protein interaction site of the β subunit comprising
contacting a G protein β subunit with a test agent in the presence of a peptide that binds at least one amino acid residue of the protein interaction site of β subunit; and
determining whether the agent inhibits the binding of the peptide to the at least one amino acid residue of the protein interaction site of the β subunit thereby identifying an agent that binds at least one amino acid residue of the protein interaction site of the β subunit.
4 . An agent identified by the method of claim 3 .
5 . A kit for identifying an agent that binds at least one amino acid residue of the protein interaction site of the β subunit, said kit comprising a SIGK peptide or SIGK peptide derivative.
6 . A method for modulating at least one activity of a G protein comprising contacting a G protein with an effective amount of an agent that interacts with at least one amino acid residue of the protein interaction site of the G protein β subunit so that at least one activity of the G protein is modulated.
7 . A method for preventing or treating a disease or condition involving at least one G protein βγ subunit activity comprising administering to a patient having or at risk of having a disease or condition involving at least one G protein βγ subunit activity an effective amount of an agent that interacts with at least one amino acid residue of the protein interaction site of the G protein β subunit so that the at least one activity of the G protein is modulated thereby preventing or treating the disease or condition involving the at least one G protein βγsubunit activity.