Fig. 3: Mating-induced silencing is actively maintained for >300 generations.
From: Mating can initiate stable RNA silencing that overcomes epigenetic recovery
a Mating-induced silencing was initiated and silencing was scored in cross progeny and their descendants. Each vertical pair of boxes represents fluorescence intensity of mCherry and GFP within the same animal (bright, dim, and off, as in Fig. 1c). b Maintenance of mating-induced silencing was measured by smFISH against mCherry exonic RNA in indicated distal region of dissected gonads of adult T, iT (silenced for ~320 generations) or wild-type animals. Pink arrowheads indicate the nucleus of the distal tip cell. Animals with median values of fluorescence or RNA signal in the distal region are shown in representative images. smFISH probes used are depicted in Supplementary Fig. 2d. Merged (DAPI + mCherry RNA smFISH) images shown here are also shown in Supplementary Fig. 6a as separate channels with remaining images from the same animals. Numbers within images indicate number of RNAs per 100 µm2 with standard error of the mean. c Left, iT hermaphrodites that showed 150–250 generations of continued silencing were crossed with males mutant for RNAi genes (g(-)) and resulting descendants homozygous for the mutant allele of the gene were scored at F3 (rde-1(-), prg-1(-), rrf-1(-), ego-1(-) rrf-1(-), nrde-3(-), hrde-1(-)), F4 (ergo-1(-), heri-1(-)), F5 (pgl-1(-), rde-3/mut-2(-), mut-16(-), set-32(-)), ~F15 (rde-8(-)) generations, or scored at F4/F6/F8 and pooled (met-2(-)). Use of prg-1(−/+) parent males owing to the poor mating by prg-1(-) parent males is indicated (§). Use of fertile ego-1(−/+) rrf-1(−/−) parent hermaphrodites, rather than sterile ego-1(-) rrf-1(-) parent hermaphrodites, mated to iT males is indicated (#). Use of Cas9-mediated genome editing rather than genetic cross to introduce mutation is indicated (°). Right, Model of piRNA-mediated RNA silencing (see text for details). Scoring of silencing (a, c) is as in Fig. 1c. Chromosomes with a dpy marker (blue font), number (n) of animals scored (c) or imaged by confocal microscopy (b) and scale bar (10 µm) are indicated. Also see Supplementary Figs. 5 and 6. Asterisks indicate P < 0.05 using χ2 test (c). Also see ‘Genetic Crosses’ under Methods. Source data are provided as a Source Data file.
