Characterization of Parasarcophaga heterochromatin. I. Mitotic chromosomes

The heterochromatin of neuroblast metaphase chromosomes in six sympatric species of Parasarcophaga was characterized by C-, N-, quinacrine (Q)-, Hoechst 33258 (H)-, Hoechst/actinomycin D (H/AMD)- and acridine orange (AO)-banding. The autosomes and the sex chromosomes in all the six species are characterized by the presence of C- and N-positive heterochromatin. The N-bands lie within the limits of the C super(+) heterochromatin. AT-specific fluorochromes further differentiate heterochromatin into Q super(+)H super(+), Q super(-)H super(+) and Q super(-)H super(-) types and the repetitive nature of these regions is indicated by their fast reassociating nature with AO-staining. Thus, on the basis of these results, the heterochromatin of mitotic chromosomes in Parasarcophaga) can be classified into C super(+)N super(+)Q super(+)H super(+), C super(+)N super(+)Q super(-)H super(-), C super(+)N super(-)Q super(-)H super(-) and C super(-)N super(-)Q super(-)H super(+) types.