High impact information on Dox-A2

• We also provide evidence that in addition to microbial products, endogenous signals from dying hemocytes contribute to triggering and/or assembly of the prophenoloxidase-activating cascade, and that this process can be inhibited in vitro and in vivo using the viral apoptotic inhibitor p35 [1].
• Drosophila prophenoloxidase is stored in crystal cells, a specialized class of blood cells from which it is released through cell rupture [1].
• The location of A. stephensi Dox-A2 was determined by in situ hybridization at 34D on chromosome arm 3R [2].
• Separation of the three phenol oxidase A component activities on polyacrylamide gels shows that Dox-A2 mutations reduce the activity of only the A2 component [3].
• Recently isolated Dox-A2 mutations (2-53.9) are recessive, early larval lethals, which as heterozygotes reduce phenol oxidase activity [3].

Biological context of Dox-A2

• The Dox-A2 locus is one of 18 loci in the dopa decarboxylase, Df (2L)TW130 region of the second chromosome, at least 14 of which affect the formation, melanization or sclerotization of cuticle in some way [3].
• By means of high pressure liquid chromatography with electrochemical detection (HPLC-ED) both phenol oxidase activities were observed in the blood (hemolymph) of two species of insect, third-stage larvae of Drosophila melanogaster and adult Locusta migratoria, and in an adult fresh-water crayfish, Austropotamobius pallipes [4].
• The Dox-A2 locus mRNA is 1.7 kb. cDNA clones indicate that the 3' end is centromere proximal and that the coding region contains at least one small intron [5].
• These results suggest that SUN2 is a functional counterpart of Dox-A2 and that these genes play a pivotal role in the cell cycle in each organism [6].
• The kinetics of the activation reactions was unusual in that the final levels of phenoloxidase activity varied depending on the initial concentrations of the activating enzyme, not those of the prophenoloxidase [7].

Anatomical context of Dox-A2

• Drosophila melanogaster diphenol oxidase A2: gene structure and homology with the mouse mast-cell tum- transplantation antigen, P91A [8].

Associations of Dox-A2 with chemical compounds

• Elevated pool sizes of the diphenol oxidase substrates DOPA, dopamine, and N-acetyldopamine are observed in the mutant, confirming the enzyme assay results [3].
• A masquerade-like serine proteinase homologue is necessary for phenoloxidase activity in the coleopteran insect, Holotrichia diomphalia larvae [9].
• The results suggested that the activation of A1 with 2-propanol is caused by the reversible conformational change of the prophenoloxidase molecule [10].

Other interactions of Dox-A2

• The diphenol oxidase activity in double mutant combinations shows that these mutations and Dox-A2 (Pentz et al., 1986) affect this enzyme in different ways [11].
• The proximal breakpoints of deficiencies Df(2L)hk18 and Df(2L)OD15 define a 14.3- to 16.8-kb region containing Dox-A2 and l(2)37Bb, and those of Df(2L)OD15 and Df(2L)TW203 define a 9.3- to 12.1-kb region containing l(2)37Ba, l(2)37Bc and l(2)37Be [5].

References