The turnover rate of the labled phenylalanine verifeies previously identified trends - later development showed greater amino acid "turnover" than did earlier stages in pharate adult development. Both labeled CO2 production and location of labeled phenylalanine supported the observation. Greater (labeled) CO2 production matched greater amino acid "turnover" and increased metabolism in the later development phase. Less labeled CO2 production occured in earlier develpment (middle stage). Radoactive label was also present in greater amounts in the gut/fat body tissues in middle stages of development (before greater "turnover" and use in tussues).
Radioactive arylphorin production of labeled Co2 rollowed a similar pattern to that of labele phenylalanine - greater production of CO2 in later development opposed to earlier development (middle stage). The production of labeled CO2 from the labeled arylphorin did lag gehind that of labeled phenylalanine initially, but this is consisten with the necessary time to degrade the arylphorin to individual amino acids (before processing).
In addition, the similar distribution patterns of the labeled arylphorin and labeled phenylalanine into body tissues in both middle and late stage pharate adult development support the hypothesis of arylphorin being a storage protein and degrading into the pool of free amino acids. Increasingly higher labeled CO2 prodcution towards the end of middle development for both labeled phenylalanine and labeled arylphorin also support the hypothesis of arylphorin as a stroage protein.
As a whole, the degradation of arylphorin appears slower during middle stage development compared with late stage development. This is supported by both significantly higher levels of labeled arylphorin in the hemolymph in comparison to the labeled phenylalanine during the middle stage of development from the hemolymph. Radioactivity levels in the hemolymph of arylphorin decrease rapidly.
In late stage development, when labeled arylphorin is degrading rapidly, 50% of the label is recovered in abdominal and thoracic muscles. This would indicate a high contribution of amino acids from arylphorin to these structures. Contribution to the cutice, however, has not been supported by the results. The highest recovery of radiolabel in the cuticle occured in middle development, when arylphorin degadation was shown to be at a low rate.