Patent ID: 8183006
Filing Date: 2012-05-22
Classification: C12Q,G01N

Abstract:
1. A screening method for identifying a candidate drug wherein said method comprises the following steps: a) obtaining a gene sequence encoding a naturally occurring aminoacyl-tRNA synthetase; b) engineering the gene sequence encoding said aminoacyl-tRNA synthetase, resulting in an aminoacyl-tRNA synthetase with a defective activity, with the proviso that the engineering does not affect the functionality of the catalytic site of the enzyme wherein the ligation of the amino acid to the tRNA is carried out; c) cloning the gene resulting from step (b) in an expression vector; d) transforming isolated mammalian cells with the expression vector resulting from step (c); e) growing the recombinant cells resulting from step (d) in a nutrient medium under conditions which allow the expression of the engineered aminoacyl-tRNA synthetase, the expression resulting in cell death or a decrease in the rate of cell division; f) providing a substance to be tested to the medium resulting from step (e); and g) analyzing the resulting cell growth, wherein if there is an increase in cell growth, then the substance selectively inhibits the activity of the engineered aminoacyl-tRNA synthetase and does not affect its cellular ortholog, resulting in that said substance is a candidate drug; wherein the naturally-occurring aminoacyl-tRNA synthetase is isoleucyl-tRNA synthetase (IleRS), and the IleRS is engineered to alter its editing domain by substituting residues corresponding to