Fluorescence in situ hybridization of 18S rRNA, 5S rRNA and H3 histone gene sequences in Rammathocerus brasiliensis without B and with 1B chromosome. (a-f) Metaphases I, (g) late diplotene and (h) diacinesis; (a) 18S rDNA; (b, e, g) 5S rDNA; (c, f, h) H3 histone; (d) DAPI only. In (c) is showed the H3 histone location in one individual from Surubim population and in the inserts in (h) are shown the hybridization patterns of 5S rDNA (red signals) and H3 (green signals) in the X and B chromosomes by two color FISH obtained from a Metaphase I. The smallest chromosome S11 that does not harbor 5S/H3 sites is indicated in (a, b, d, e, f). The X and B chromosomes, and chromosomes bearing specific hybridization (for 18S rDNA and H3 histone) signals are also indicated. Note the dispersion and co-localization of 5S rDNA and H3 histone sites, and the co-localization of 18S and 5S rDNA in three chromosomes. The meiotic plates in (g, h) are incomplete, lacking autosomes, but the X and B chromosomes are easily recognizable by their condensation patterns and univalent behavior. Chromosomes are counterstained with DAPI and the group of images (a, b) and (d, e, f) are the same metaphases submitted to two color FISH. Each bar = 5 μm.