Figure 6.

Autoradiographs of ³H-labeled HeT-A^mel probes hybridized to D. simulans polytene chromosomes. (A) Coding region probes hybridize to telomeres (arrowheads) and to one spot in the pericentric heterochromatin (arrow). (As with D. melanogaster, there are different levels of hybrid over different chromosome ends. Amounts of hybridizing material tend to be chromosome-specific within a given stock.) The pericentric spot may represent telomeres of the short arms of chromosomes 4 and X. (B) Probes from the 3′ noncoding region hybridize to telomeres and generally over the pericentric heterochromatin, showing that in pericentric regions some 3′ noncoding sequence may exist free of the coding regions.