Identification of new EGA repressors.

<p>(A) Schematic representation of a genetic screen, performed to identify novel regulators of EGA in the adult germline. The EGA-GFP reporter was used to monitor transcriptional reprogramming occurring during the oocyte-to-embryo transition (green indicates embryonic transcription). Wild-type animals express EGA-GFP in embryos. Mutant animals abnormally express this reporter in germ cells. (B) Fluorescent micrographs of live animals expressing the EGA-GFP reporter. Here, and in the subsequent figures, gonads are outlined with a continuous line and asterisks mark the distal end of the gonad. The dashed line in the top panel outlines the embryos. While wild-type animals express the EGA-GFP specifically in embryos, the <i>lin-41(rrr3)</i> mutants express it in proximal gonadal cells undergoing a germline-to-soma transition. The new mutants (the <i>rrr2</i> mutant is shown as an example) express EGA-GFP precociously in developing oocytes. Arrows point to three representative, arbitrary chosen, nuclei displaying EGA-GFP. Scale bar: 40 μm. (C) Complementation matrix of newly (<i>rrr2</i>, <i>rrr5</i>, and <i>rrr9</i>) and previously (<i>gld-1(q485)</i> and <i>lin-41(rrr3)</i>) identified mutants displaying premature EGA. “WT” indicates complementation and “EGA” non-complementation. The <i>rrr2</i> and <i>rrr5</i> mutants did not complement each other, suggesting that they affect the same gene.