Figure 1

An illustration of gene neighborhoods and chromosome territories. (a) A heat diagram showing normalized hybridization intensities along a segment of a Drosophila chromosome. Samples are arrayed from left to right, and samples from testis and males (including testis) are indicated; genes that are adjacent on chromosome 3R are listed from top to bottom. Four contiguous genes, including the don juan gene (dj) that encodes a sperm tail protein, show testis-biased and male-biased expression. Figure generated using data from [16]. (b) A micrograph of liver cells, showing the positions that two chromosomes preferentially occupy within the nucleus. Chromosome 12 (green) is frequently found towards the periphery, whereas chromosome 15 (red) tends to localize towards the center of the nucleus. Blue indicates total DNA staining.