System to monitor crossovers on chromosome XII.

Abstract

<p>A diploid was constructed with heterozygous markers immediately centromere-proximal to the ribosomal RNA (rRNA) gene clusters (<i>HYG</i>), within the rRNA gene cluster (<i>TRP1</i>), and immediately centromere-distal to the cluster (<i>URA3</i>) <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1003894#pgen.1003894-Casper1" target="_blank">[34]</a>. G1-synchronized cells were treated with UV, plated on solid medium and grown non-selectively. The resulting colonies were replica-plated to medium lacking uracil, tryptophan, or containing hygromycin as described in the text. A. Sectoring pattern expected for a crossover centromere-proximal to the <i>HYG</i> marker. B. Sectoring pattern expected for a crossover within the rRNA gene cluster centromere-proximal to <i>TRP1</i>. C. Sectoring pattern expected for a crossover within the rRNA gene cluster centromere-distal to <i>TRP1</i>.</p