Effects of precocene II on female‐specific hemolymph polypeptides in Oncopeltus fasciatus

Abstract

Using polyacrylamide gel electrophoresis (PAGE) under denaturing conditions, two major polypeptides of 200,000 and 170,000 daltons were detected in the hemolymph of mature female Oncopeltus fasciatus, but they were not found in the hemolymph of males or newly emerged females. Those polypeptides constituted the two major bands of early vitellogenic oocytes; however, they were absent from the yolk of mature eggs. The slower‐migrating band (200,000 daltons) appears to correspond to a vitellogenic protein already identified in O. fasciatus, whose synthesis has been suggested to be independent of juvenile hormone (JH). Treatment of newly emerged adult females with the corpus allatum cytotoxin precocene II prevented the appearance of the female‐specific bands and induced an important accumulation of other proteins in the hemolymph. Yolk deposition was also inhibited in those animals. Topical application of JH to precocene‐treated females restored the appearance of the 200,000 and 170,000 dalton polypeptides in the hemolymph. These results suggest that JH is required for the synthesis of female‐specific polypeptides in O. fasciatus.

Ovary Development and Maturation in Nezara viridula (L.) (Hemiptera: Pentatomidae)

“…In Heteroptera, vitellogenesis is mainly regulated by the juvenile hormone, while ecdysteriods have a discrete role (Dittmann & Biczkowski 1995, Davey 1997. The juvenile hormone regulates not only vitellogenin (Vg) synthesis, but also Vg uptake (Martinez & Garcera 1987, Hirai et al 1998.…”

Identification, purification, and partial characterization of vitellin from the eggs of Eurygaster integriceps putton (heteroptera, pentatomidae)

“…The red cotton bug major yolk protein has two major subunits of 180 kDa and 175 kDa, which proved to be female specific, and additional bands in the 210 kDa to 56 kDa range (Dittmann et al, 1985). The two main vitellogenic polypeptides of OncopeEtus fusciutus of 200 kDa and 170 kDa are not found in the yolk of mature eggs, which in turn contains five major polypeptides with molecular masses from 93 kDa to 40 kDa (Martinez and Garcera, 1987). These data could be explained, assuming that partial or complete additional cleavage of vitellogenin during oocyte maturation takes place.…”

Physiological Activities of Anti-Juvenile Hormone Agents Against Insects and Their Role For Devising Fourth Generation Insecticides: A Comprehensive Review

“…Also, precocene treatment was found to inhibit the protein synthesis in fat body of banana fruit fly Zaprionus paravittiger (Rup and Bangla, 1995;Amiri et al, 2010). In Hemiptera, treatment of the newly emerged adult females of O. fasciatus with PII prevented the appearance of the female-specific polypeptide bands but induced the accumulation of other proteins in the haemolymph (Martínez and Garcerá, 1987). After treatment of E. integriceps nymphs with PI, haemolymph protein level in adult females was lower than the control adults, at first day after treatment.…”