The genome-wide screen to identify hyper-GCR mutants.

<p>(<b>A</b>) Experimental construct in the query strains. 100% homologous or 94% homeologous <i>Alu</i>-IRs were inserted into the left arm of chromosome V. The selectable marker <i>hphMX</i> for the presence of the chromosomal fragment containing the repeats and the counterselectable marker <i>CAN1</i> used to assay GCR events are depicted. (<b>B</b>) Representative plate showing papillae on canavanine-containing medium reflecting the levels of <i>Alu</i>-IR-induced GCRs in wild-type and mutants. Columns are duplicates of query strains containing 100% homologous or 94% homeologous <i>Alu</i>-IRs. Each row is a tester strain containing the corresponding mutation. (<b>C</b>) Experimental construct for verifying the effect of hyper-GCR mutants obtained from the screen. <i>ADE2</i> was inserted between <i>CAN1</i> and the repeats. As a result, GCR events appear as red Can^R colonies and mutations at <i>CAN1</i> give rise to white Can^R colonies on canavanine-containing medium with low amounts of adenine.