Molecular cytogenetic characterization of all 14 pairs of C. intestinalis chromosomes. (A) Strategy for identifying all 14 pairs of C. intestinalis chromosomes simultaneously. BAC probes used are shown on chromosomes they are predicted to recognize; chromosome 1: GECi18_g12 (red) and GECi41_h20 (red), both on the long arm (the GECi designation was omitted in the figure); chromosome 2: 38_p05 (green) and 48_g02 (green), both on the long arm; chromosome 3: 23_j02 (green) on the short arm and 41_j13 (green) on the long arm; chromosome 4: 17_m21 (rDNA probe; red) on the short arm; chromosome 5: 17_m21 (rDNA probe; red) on the short arm and 47_l17 (green) on the long arm; chromosome 6: 17_m21 (rDNA probe; red) on the short arm and 26_m10 (red) on the long arm; chromosome 7: 37_e03 (green) on the long arm; chromosome 8: 31_b20 (red) on the long arm; chromosome 9: 30_d14 (red) on the short arm; chromosome 10: 26_m14 (red) on the short arm and 30_f09 (red) on the long arm; chromosome 11: 39_o18 (green) and 45_b12 (red), both on the short arm; chromosome 12: 45_o05 (green) and 16_k11 (red), both on the long arm; chromosome 13: 20_b17 (green) on the short arm and 46_d01 (red) on the long arm; and chromosome 14: 40_e22 (green) on the short arm. (B) Karyotyping of all 14 pairs of C. intestinalis chromosomes by FISH. Metaphase chromosomes were counterstained with DAPI and imaged monochromatically. The centromere regions were brightly stained. Scale bar, 2 μm.