Figure 5. UNC-62 binds to and activates expression of all six C. elegans yolk protein genes.

(A) The thick and thin blue lines indicate the exon and intron structure of each of the six vitellogenin loci. Red boxes indicate the position of regions significantly enriched in UNC-62 ChIP-seq of day 4 adult (YA) worms. (*) indicates q-value<0.001 and (**) indicates q<10⁻⁵ binding sites. Below each gene, RNA-seq results are displayed for worms fed either unc-62 RNAi or control bacteria. Bars indicate the mean, and error bars the standard deviation, of sequencing read density (reads per million mapped reads) for vitellogenin genes in triplicate RNA-seq experiments. (B) Bars indicate mean, and error bars indicate standard deviation, of measured fluorescence of a vit-2:GFP reporter under various RNAi conditions. Expression in ∼15 worms was quantified using ImageJ. (C) (top) A de novo motif search in UNC-62 young adult binding sites with RSAT [58] identifies a TGATTGACA motif as the prominent sequence motif. (bottom) This motif is similar to the ATTGACA VPE-1 vitellogenin regulatory motif previously described [30]. (D) All six vitellogenin genes decrease expression with age (as assayed by whole-worm microarrays of 2, 5, 8, and 11 day old adult worms [10]). Bars indicate mean expression observed across replicated arrays, with error bars indicating standard deviation. (E) UNC-62 activates vitellogenin expression in old adults. Bars indicate expression of two biological replicates of vit-2 (black) and vit-6 (grey), determined by qRT-PCR of RNA isolated from ∼100 dissected intestines of day 1 adults and day 15 adults fed either control or unc-62 RNAi bacteria. Error bars indicate standard deviation of triplicate qPCR technical replicates. Statistical significance is not indicated as this experiment included only two biological replicates.