Polymorphism of prophenoloxidase in the silkworm, Bombyx mori

We reported that the hemolymph of the a80 strain of the silkworm, Bombyx mori, included three isoforms of prophenoloxidase, a proenzyme of phenoloxidase. However, their heterogeneity in strains other that a80 has not been investigated. On polyacrylamide gel electrophoresis followed by activity staining for this protein, we discovered that two pro-PO isoforms were revealed in the larval hemolymph of some strains, two strains have three isoforms in their hemolymph, and only hemolymph of a481 strain contain one isoform among silkworm strains we tested. In this paper, we confirmed the polymorphism of prophenoloxidase.