Synthesis dynamic and developmental profile of prothoracicotropic hormone between diapause- and nondiapause-destined individuals in Helicoverpa armigera

摘要

Biosynthesis and secretion of prothoracicotropic hormone (FTTH) of diapause- and nondiapausedestined individuals in Helicoverpa armigera were studied using whole-mount immunocytochemistryand enzyme-linked immunosorbent assay (EUSA). The immunocytochemistry revealed that PITH isexpressed in two pairs of lateral neurosecretory cells of the brain. The presence of immunoreactivityhas not significant difference between the brains of the diapause- and nondiapause-destined 6th instarlarvae. However, the obvious differences of expressional pattern from day 4 pupae were observed between the two types. PTTH titers in hemolymph from the 6th instar larvae to pharate adults weremeasured by the ELISA. Although there were similar liter changes between the two types of individualsat the larval stage, a significant difference from developmental expression was detected at the pupalstage, suggesting that the expression and secretion of PTTH does play a crucial role in regulation ofpupal diapause of H. armigera.