Extended Data Fig. 4: Time-course of conditional cdk-1 silencing using auxin.
From: Reprogramming the piRNA pathway for multiplexed and transgenerational gene silencing in C. elegans
a. Brightfield image of animals with piRNAi targeting cdk-1 in the AID::PRG-1 strain on auxin (left panel) or off auxin (right panel). The dotted yellow line outlines fertilized embryos in the hermaphrodite uterus. Arrows indicate the vulva and embryos. cdk-1 encodes a cyclin-dependent kinase that is required for cell division and embryos arrest at the single-cell stage in cdk-1 mutants. Representative images from more than ten embryos imaged. Scale bar = 25 µm. b. piRNAi against cdk-1 in the AID:PRG-1 strain. Injected animals were maintained on 1 mM auxin plates (to deplete PRG-1). L4 stage animals were transferred to plates with or without auxin and surviving progeny was scored by first counting eggs and three days later counting the total number of adult progeny. Negative control = wildtype animals (N2). Kruskal-Wallis ANOVA P = 0.0036, Dunn’s multiple comparison * P = 0.0146, ns P = 0.3594. c. piRNAi activation after removal from auxin. To determine how long it takes to ‘turn on’ piRNA-mediated silencing after auxin removal, animals were transferred to non-auxin plates at each larval stage and at 3-hour intervals as young adults. The uteruses of adult animals (at least 11 animals) were scored for the presence of single-cell arrested embryos. Data are presented as mean values+/− SEM with each data point corresponding to an independently derived transgenic strain. Sample sizes (b) n = 3 (N2), n = 3 (auxin, both conditions), (c) n = 1 (all conditions) biologically independent transgenic strains.
