(A) Deconvolution microscopy of Drosophila larval neuroblasts in early prophase expressing GFP-Prod (green) under the control of wor-gal4 and stained with pH3 (Ser10) (red). Arrowheads in the inset indicate two of the four Prod loci while the arrow indicates Prod threads connecting the two loci. (B) Schematic depicting how homologous chromosomes separate into distinct ‘territories’ in spermatocytes in preparation of meiotic reductional division. One territory contains the X, Y, and 4th chromosomes, a second territory contains the 2nd chromosomes, and a third territory contains the 3rd chromosomes. (C) FISH against the {AATAACATAG}n satellite (red) in spermatocytes expressing GFP-Prod (green) under the control of bam-gal4 and stained with DAPI (blue). Yellow line demarcates chromosome 2 and chromosome 3 territories. Arrow indicates chromatin thread linking the two territories that is positive for DAPI, Prod, and the {AATAACATAG}n satellite DNA. (D) FISH against the dodeca satellite (red) and the {AACAC}n satellite (blue) in spermatocytes GFP-Prod (green) under the control of bam-gal4 and stained with DAPI (white). Yellow line demarcates chromosome 2 and chromosome 3 territories. Arrowhead indicates chromatin thread linking the two territories that is positive for DAPI and Prod. Arrows indicate location of {AACAC}n satellite DNA that is specific to chromosome 2 and dodeca satellite DNA that is specific to chromosome 3. All scale bars are 5 μm.