The regulatory region of <i>mil-1</i> becomes hypomethylated during PGC development.

<p>Bisulfite sequencing analysis of the regulatory region of <i>mil-1</i> was performed using epiblasts, PGCs/somatic cells purified as GFP positive/negative cells from embryos at each embryonic day (E). The rectangle containing <i>mil-1</i> in the top line represents an exon, and the numbers with ‘kb (kilobase)’ under the line indicate distance from the transcription start site (TSS). The box outlined in green represents the regulatory element required for PGC-specific expression and the <i>Ifitm</i> genes consensus element (ICE) is shown in more detail in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0046036#pone-0046036-g004" target="_blank">Figure 4A</a>. Each circle corresponds to a CpG site in the regulatory region, and the degree of gray in each circle corresponds to the level of DNA methylation.