Isozymes of diapause and non-diapause pink bollworm larvae, Pectinophora gossypiella

Abstract Diapausing and non-diapausing pink bollworm larvae were assayed by starch gel electrophoresis for 15 enzymes, including 9 glucose-metabolizing enzymes. Mobility differences between individuals were shown for 5 enzymes. Leucine aminopeptidase and alkaline phosphatase decreased in activity by mid through late diapause, reflecting a decrease in anabolic processes during diapause. Lactate dehydrogenase and glyceraldehyde-3-phosphate dehydrogenase, 2 enzymes of glycolysis, show changes in mobility between diapause and non-diapause larvae. By late diapause there was a complete loss of activity for both enzymes. Differences in mobility and loss of activity of G-3-PDH may result from a lack of either available phosphorus or NAD, or both. Our data indicate that all of the G-3-PDH is in the acyl-enzyme form in diapause, suggesting that the glycolytic pathway is blocked at glyceraldehyde-3-phosphate.