L-Dopa decarboxylase mRNA levels are correlated with the L-dopa decarboxylase protein profile during the development of the insect Ceratitis capitata

L-Dopa decarboxylase (DDC) activity was determined throughout the life cycle of Ceratitis capitata. Basal levels of enzyme activity were observed in 4-day-old larvae with the activity peaking at white puparium and adult eclosion stages. The increasing enzyme activity observed at these stages, is matched by an increase of the L-dopa decarboxylase protein, as shown by immunoblotting with a polyclonal antibody raised against DDC purified from the stage of eclosion of the insect Ceratitis capitata. Immunoprecipitation analysis revealed the presence of DDC in the in vitro polysomal and reticulocyte lysate translated products, obtained from white puparium and eclosion stages with no DDC detectable in 4-day-old larvae. The Northern blot analysis performed with a 4 kb HpaI fragment of Drosophila melanogaster Dopa decarboxylase gene confirmed the results obtained by Western blot analysis and by immunoprecipitation of DDC in the in vitro translated products of 4-day-old larval white puparium and eclosion stages.