Non-autonomous pteridine formation induced by implantation of wild-type malpighian tubules in two different lines of the mutantMaroon-like (ma-l) ofDrosophila melanogaster

Summary

• 1. By implanting wild-type larval Malpighian tubules into male mutant larvae, non-autonomous pteridine formation was induced in two different lines (W: white testes; G: yellow testes) of the mutantmaroon-like (ma-l) ofDrosophila melanogaster. The amounts of various pteridines formed in the testes and the heads of individual flies were determined by paper chromatography and fluorometry. Non-operated animals of the same mutant line and the same posthatching age served as controls.

• 2. The results confirm and extend earlier data (Hadorn, Hanly andGandolla 1962). The amounts of pteridines found in the controls are generally in agreement with those data; new is the fact that the amounts of HB-pteridines in the heads of the W-controls are higher than those in the heads of the G-controls.

• 3. The two lines react to the implantation of wild-type Malpighian tubules in a similar way with respect to the following phenes: a) isoxanthopterin (equal amounts induced); drosopterins (increase about equal); c) sepiapteridines in the testes (increase in both lines); d) sepiapteridines in the heads (no change).

• 4. With respect to the HB-pteridines the reactions to the implantation are quite different in the two lines. In the G-line there is no change in either testis-HB or head-HB. In contrast, the experimental animals of the W-line show a strong increase in testis-HB, but at the same time a significant decrease of HB-pteridines in the head.