The ontogeny of dopachrome isomerase isozyme patterns in the tobacco hornworm Manduca sexta.

Melanogenesis in animals is initiated by tyrosinase and augmented by recently discovered dopachrome isomerase. Mushroom tyrosinase embedded 5% polyacrylamide gels are used to specifically stain for dopachrome isomerase activity after electrophoretic separation. Using this new procedure, the ontogenic changes in dopachrome isomerase are demonstrated for the first time in any organism. While there is no isozyme variation within the same stage of development, there are profound variations in isozyme patterns during the developmental stages from egg to adult, indicating differential expression and/or processing of dopachrome isomerase genes to match the metabolic needs at these stages.