Peptide modulators of cellular phenotype and bi-nucleic acid fragment library

A non-hybrid method for identifying a peptide capable of modulating a phenotype in a cell, tissue or organism, said method comprising:

• (i) selecting or obtaining a cell, tissue or organism capable of expressing the phenotype, wherein the phenotype is death and/or reduced growth of the cell, tissue or organism;
• (ii) expressing in the cell, tissue or organism (i) or introducing into the cell tissue or organsism (i) or contacting the cell, tissue or organsism (i) a peptide that mimics the structure of a domain or subdomain of a native protein;
• (iii) selecting a cell, tissue or organism at (ii) that survives and/or is capable of growing;
• and
• (iv) identifying the expressed or introduced peptide that induces survival and/or growth of the selected cell, tissue or organism (iii), wherein the peptide does not induce survival or growth of the cell, tissue or organism in its native environment.

A method for identifying a peptide capable of inducing cell growth on a cell that is dependent on the presence of a cytokine for cell growth, said method comprising:

• (i) selecting or obtaining a cell that is dependent on the presence of a cytokine for cell growth;
• (ii) expressing in the cell or introducing into the cell or contacting the cell with a candidate peptide that mimics the structure of a domain or subdomain of a protein;
• (iii) maintaining the cell in the absence of the cytokine for a time sufficient for cell growth to occur;
• (iii) selecting a cell capable of growing at (iii);
• and
• (iv) identifying the expressed or introduced peptide that induces cell growth, wherein the peptide does not induce growth of the cell in its native environment.

A method for identifying a peptide capable of inhibiting cell death induced by expression of Aurora-A kinase in a yeast cell, said method comprising:

• (i) obtaining or producing a yeast cell capable of overexpressing Aurora-A kinase;
• (ii) expressing in the cell or introducing into the cell or contacting the cell with a candidate peptide that mimics the structure of a domain or subdomain of a protein;
• (iii) selecting a cell capable of growing at (ii);
• and
• (iv) identifying the expressed or introduced peptide that inhibits cell death, wherein the peptide does not inhibit death of the cell in its native environment.

A method for identifying a peptide capable of inhibiting cell death induced by expression of cyclin-E in a yeast cell, said method comprising:

• (i) obtaining or producing a yeast cell capable of overexpressing cyclin-E;
• (ii) expressing in the cell or introducing into the cell or contacting the cell with a candidate peptide that mimics the structure of a domain or subdomain of a protein;
• (iii) selecting a cell capable of growing at (ii);
• and
• (iv) identifying the expressed or introduced peptide that inhibits cell death, wherein the peptide does not inhibit death of the cell in its native environment.