Abstract: A method of reducing damage to cells and tissue caused by an ischemic or hypoxic event is disclosed. The method includes administering to the cell or tissue, either in vivo or ex vivo, &psgr;&egr;RACK peptide. The peptide can be administered before, during or after the ischemic or hypoxic event.

Abstract: Peptides able to inhibit or activate the translocation or function of &dgr;PKC are identified. Administration of the peptides for protection or enhancement of cell damage due to ischemia is described. Therapeutic methods to reduce damage to cells or to enhance damage to cells due to ischemia are also described, as well as methods for screening test compounds for &dgr;PKC-selective agonists and antagonists.

Abstract: The present invention relates to a polypeptide composition effective to alter the activity of a first protein that interacts with a second protein, where the second protein contains at least one WD-40 region. The polypeptides of the present invention typically have between 4 and 50 amino acids whose sequence is the same as a sequence of the same length in the WD-40 region of the second protein. The invention further includes a method of altering the activity of the above described first protein. In one embodiment of the invention the polypeptide composition is effective to alter the activity of a protein kinase C, where the protein kinase C interacts with a second protein, and the second protein contains at least one WD-40 region (e.g., RACK1).

Abstract: The present invention relates to a polypeptide composition effective to alter the activity of a first protein that interacts with a second protein, where the second protein contains at least one WD-40 region. The polypeptides of the present invention typically have between 4 and 50 amino acids whose sequence is the same as a sequence of the same length in the WD-40 region of the second protein. The invention further includes a method of altering the activity of the above described first protein. In one embodiment of the invention the polypeptide composition is effective to alter the activity of a protein kinase C, where the protein kinase C interacts with a second protein, and the second protein contains at least one WD-40 region (e.g., RACK1).

Abstract: The present invention relates to a polypeptide composition effective to alter the activity of a first protein that interacts with a second protein, where the second protein contains at least one WD-40 region. The polypeptides of the present invention typically have between 4 and 50 amino acids whose sequence is the same as a sequence of the same length in the WD-40 region of the second protein. The invention further includes a method of altering the activity of the above described first protein. In one embodiment of the invention the polypeptide composition is effective to alter the activity of a protein kinase C, where the protein kinase C interacts with a second protein, and the second protein contains at least one WD-40 region (e.g., RACK1).

Abstract: Isozyme-specific agonists or activators of .epsilon.PKC are disclosed. The agonists include peptides corresponding to the region of .epsilon.PKC between about amino acids 85 and 92. Also disclosed are therapeutic methods employing such .epsilon.PKC-specific agonists to induce preconditioning and thereby reduce injury due to subsequent ischemia, as well as methods for screening test compounds for .epsilon.PKC-selective agonist properties.

Abstract: Methods for assessing libraries of candidate modulators of intracellular signaling transmission pathways are described. The methods assess the ability of candidates from the library to inhibit the binding of peptides which represent participants in the signaling pathways as either a signal-generating protein or its cognate partner binding at a noncatalytic site. Specific peptides useful in this regard have been identified.

Abstract: The present invention relates to a polypeptide composition effective to alter the activity of a first protein that interacts with a second protein, where the second protein contains at least one WD-40 region. The polypeptides of the present invention typically have between 4 and 50 amino acids whose sequence is the same as a sequence of the same length in the WD-40 region of the second protein. The invention further includes a method of altering the activity of the above described first protein. In one embodiment of the invention the polypeptide composition is effective to alter the activity of a protein kinase C, where the protein kinase C interacts with a second protein, and the second protein contains at least one WD-40 region (e.g., RACK1).