Genetic variants of protease inhibitors against fungal protease and ?-chymotrypsin from hemolymph of the silkworm, Bombyx mori

Abstract

Many electrophoretic variants of hemolymph inhibitors of proteases from Aspergillus melleus and pancreatic alpha-chymotrypsin were found using 126 silkworm strains. Six inhibitors of the fungal protease were detected and eight of chymotrypsin; the distribution of inhibitors among Japanese, Chinese, and European races was investigated. Comparison of electrophoretic patterns from F1 hybrids and parents showed that the offspring produce inhibitors of both parental types. Segregation in F2 and backcrossing suggest that the expression of each inhibitor is controlled in most cases by a pair of alleles which are responsible for strong and null bands. Two bands of fungal protease inhibitors C and D were controlled by codominant alleles. These results suggest that polymorphism of hemolymph protease inhibitors in the silkworm would be a useful experimental system for the study of the genetic control of protease inhibitors.

A novel variant of acid phosphatase isozyme from hemolymph of the silkworm, Bombyx mori.

“…Electrophoretic variants are widespread in the silkworm, Bombyx mori (Yoshitake and Akiyama, 1964;Eguchi et al, 1965Eguchi et al, , 1984Eguchi and Yoshitake, 1967;Gamo, 1968Gamo, , 1978Gamo, , 1982 as well as other animals. It is noteworthy, however, that the phosphatase E is an isozyme showing different properties, that is, acid phosphatase isozymes would comprize heterogeneity not only in non-catalytic sites but also in the catalytic site.…”