Deleterious effect of null phenoloxidase mutation on the survival rate in Drosophila melanogaster

The effect of null activity of phenoloxidase on the survival rate was inves tigated in mutants of Drosophila melanogaster. Mox(GM95) and Dox-3(KD95), s tructural genes for prophenoloxidase A(1) and A(3), were found in natural p opulations in the former Soviet Union, and affected the phenoloxidase activ ity in active A(1) or A(3), respectively. After linking the visible markers located on the second chromosome together with the variants, cross experim ents were performed to make homozygote, rdo Dox-3(KD95) pr c Mox(GM95) wt. No double mutant had emerged. In the mutant, c Mox(GM95) wt Pu-2, the viabi lity was greatly reduced. These results suggested that phenoloxidase and ty rosine-3-hydroxylase act as indispensable proteins to maintain life in Dros ophila. (C) 1999 Elsevier Science Ltd. All rights reserved.