Abstract
In order to inquire into the possible role of flavine and pteridine in the tumor-formation of Drosophila melanogaster, early third-instar larvae of wild, v, tu, and v tu flies have been investigated with the following results: 1) Iso-xanthopterine and flavine, probably flavine-adenine-di-nucleotide, were extracted from the materials and identified electrophoretically, paper-chromatographically and fluoro-spectropho-tometrically. 2) Iso-xanthopterine and flavine were quantatively measured with the Beckman-spectrophotometer with the use of extracts from the paper-chromatograms of larvae which were cultured in synthetic media different in quantity of riboflavine and xanthopterine.
Melanotic tumor-incidence and viability of flies cultured in the media with different amounts of riboflavine and xanthopterine were also investigated.
Based on the results of the above experiments, the suggestion may be possible that flavine is intimately related to the tumorformation itself in competition with isoxanthopterine.
A scheme was presented to illustrated melanization, tryptophane metabolic pathway, and metal, flavine and iso-xanthopterine metabolisms in relation to the formation of the melanotic tumor in Drosophila.
