Figure 1.

The tight linkage of grasshopper Scr, abd-A, Abd-B, and SgDax, as revealed on metaphase and interphase spreads (blue). (a) Metaphase chromosomes surrounded by interphase nuclei with the major ribosomal gene loci (red). (b) Metaphase with homologous chromosomes showing two Scr (green) signals and one Abd-B (red) signal each. The Abd-B signal in the right inset is faint because it is in a slightly different focal plane from the other signals. (c) Metaphase with Scr (red) and histone and ribosomal markers (green). (d) Metaphase with a single chromosome showing two abd-A (red) signals and one SgDax (green) signal. (e) Metaphase with a single chromosome (yellow arrowhead) bearing two abd-A (red) signals and one SgDax (green) signal. (f) Interphase with two Scr (red) and two SgDax (green) signals. (g) Interphase with two SgDax (green) and two abd-A (red) signals. (h) Interphase with two abd-A (red) and two Scr (green) signals (yellow arrowheads). Insets show enlargements of the signals. (Bars = 10 μm.)