Ontogenetic Survey of Histone Modifications in an Annelid

Figure 5

H3K4 dimethylation in Polydora cornuta. (a, b) Companion micrographs of an oocyte inside the coelom of a female in paraffin section showing nuclear DNA (a, DAPI) and nuclei that are dimethylated at H3K4 (b, FITC-conjugated anti-H3K4me2). Note that H3K4me2 was not detected in the oocyte nucleus. (c–e) Early cleavage stages of a planktotrophic embryo in bright field (c) and with epifluorescence for DAPI (d) and FITC-conjugated H3K4me2 (e). The small arrows indicate the presence of H3K4me2 in the micromeres. (f, g) Three-chaetiger larva from a P-brood in bright field (f) and with epifluorescence for FITC-conjugated H3K4me2 (g). e: eye, ep: epidermis, g: gut, ls: larval spines, m: mesoderm, on: oocyte nucleus, s: septa, and p: pygidium. Scale bars = 50 μm.