<i>mrg-1</i> (<i>lf</i>) fails to form bivalents when combined with germline apoptosis mutations.

<p>(A) Full projections of optically sectioned indirect immunofluorescence images of HIM-3 (green) with DAPI-stained DNA (blue) in oocytes from the -1 to -3 positions. The periphery of each oocyte is indicated by the dotted circle. Both the <i>ced-4</i> (left) and <i>mrg-1</i> (right) single mutants typically display six DAPI-stained bodies with cross-shaped HIM-3 staining per oocyte, demonstrating successful bivalent formation. The <i>ced-4 mrg-1</i> double mutant (middle) often displays diakinesis oocytes with more than six DAPI-stained bodies, some of which lack cross-shaped HIM-3 staining, indicating failed bivalent formation. Bar: 20 μm. (B) Histogram showing the percentage of gonads with oocytes from the -1 to -3 positions displaying more than six DAPI-stained bodies. The <i>ced-3; mrg-1</i>, <i>ced-4 mrg-1</i>, and <i>ced-9; mrg-1</i> double mutants display a substantially greater number of oocytes with more than six DAPI-stained bodies in at least one of three late diakinesis oocytes. This increase is statistically significant compared with the <i>mrg-1</i> single mutant (p = 0.0057, p<0.0001, p = 0.0067, respectively, Fisher’s exact test).