Primers used for bisulfite sequencing.

<p>Primers used for bisulfite sequencing.</p

Sequences of adaptors and primers used in ms-AFLP analyses.

<p>Sequences of adaptors and primers used in ms-AFLP analyses.</p

In the dependent lineage (genetic caste determining) <i>Pogonomyrmex</i>, queens obligately mate within and between lineages (the lineage pair J1/J2 are pictured here) in order to produce a functional colony.

<p>Hybrid matings produce workers (horned symbols), while within lineage, “pure”, matings produce reproductive females (future queens). Diagnostic microsatellite markers can be used to assess the parentage of individuals at any point during development, even prior to their physical differentiation.</p

Methylation profile for three genes.

<p>The red rectangle represents the portion of this gene that was amplified by the nested primers. Below the full gene figure is a zoom view of the amplified gene area. Below the amplified area are squares representing the methylation profile of the area. Open squares represent an unmethylated CpG. Black squares represent a methylated CpG. Red squares represent a methylated CpA, Blue squares represent a methlyated CpC, Green squares represent a Methylated CpT. “W” stands for “worker”. “Q” stands for “queen”. Below each methylation profile is an “N>1” sequence which displays sites found to be methylated in more than one sample. The number of squares represents the number of times the site was found. A “Q” or a “W” was placed under the site denoting if the multiple-sample site was relegated to that caste.</p

Global trends of CpG methylation.

<p>a) The proportion of methylated loci increases in queens in adulthood, but is constant for workers over development. Only adult workers and virgin queens differed, with virgin queens having significantly more methylated DNA (P<0.05). In b) variation in the proportion of methylated loci between workers of different hybrid origin. Labels indicate the maternal lineage; all workers are hybrids between the J1 and J2 lineages. The direction of hybridization affected the degree of methylation, with workers from J1 mothers and J2 fathers being 17% more methylated (P<0.05) than those from the reciprocal cross. In c) a comparison between four lineages: <i>P. barbatus</i> and <i>P. rugosus</i> have normal (environmental) caste determination and ancestrally hybridized to give rise to the J lineages (which have genetic caste determination). The J lineages are significantly less methylated (P<0.05) than their parental species. Together, b) and c) show that two successive rounds of hybridization both changed the degree of genome methylation present in workers. All error bars are 95% C.I. Numbers inside the bars indicate sample sizes, and the number of colonies from which individuals were sampled (in parentheses).</p

The frequency, and mean, of each type of CpN methylation observed for each gene studied in all samples.

<p>The frequency, and mean, of each type of CpN methylation observed for each gene studied in all samples.</p