Dosage compensation and ontogenic expression of suppressed and transformed Vermilion flies in Drosophila.

A spectrofluorometric assay system for tryptophan oxygenase was used to compare dosage compensation properties and ontogenic expression of suppressed, "transformed," and wild-type vermilion flies. The results indicate that, although different stocks showed different levels of oxygenase activity, all showed dosage compensation properties. The ontogenic expression of tryptophan oxygenase was observed to be different in the various genotypes. Whereas suppressed vermilion resembled wild type in its pattern, the ontogenic profiles of "transformed" flies were different.