In vitro action of prothoracicotropic hormone on RNA-synthesis in the prothoracic gland of the silkworm, Bombyx mori

1986 ◽  
Vol 32 (8) ◽  
pp. 711-717 ◽  
Author(s):  
Yasuo Aizono ◽  
Noboru Matsuo ◽  
Yoshihiro Yoshida ◽  
Gunki Funatsu ◽  
Masaru Funatsu ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Rna Synthesis ◽  
Prothoracic Gland ◽  
Prothoracicotropic Hormone ◽  
Silkworm Bombyx Mori

In Vitro Culture of Embryos in the Silkworm, Bombyx Mori L

1963 ◽  
Vol 40 (4) ◽  
pp. 735-739
Author(s):  
TAKEO TAKAMI
Keyword(s):  
In Vitro Culture ◽  
Bombyx Mori ◽  
Embryo Culture ◽  
Prothoracic Gland ◽  
Prothoracic Glands ◽  
Hormonal Action ◽  
Bombyx Mori L ◽  
The Brain ◽  
Silkworm Bombyx Mori

1. Silkworm embryos decapitated before the differentiation of neuroblasts, or before differentiation of the prothoracic glands, were cultured in vitro. 2. Brainless embryos which developed from these decapitated explants detached the cuticle, suggesting that the ‘moult’ of cultured embryos does not require any hormonal action of the brain in the silkworm at least for its initiation. 3. The prothoracic gland was not found to be necessary even for occurrence of the embryonic moult. 4. The author's results obtained by embryo culture in the silkworm are contrary to those obtained by ligaturing experiments in the locusts. This difference between the two cases present important questions about the nature of the moult in cultured silkworm embryos, which must be answered by further investigations.

scholarly journals Vitellogenin receptor selectively endocytoses female-specific and highly-expressed hemolymph proteins in the silkworm, Bombyx mori

2017 ◽  
Vol 95 (4) ◽  
pp. 510-516 ◽  
Author(s):  
Chaoshan Han ◽  
Enxiang Chen ◽  
Guanwang Shen ◽  
Zhixin Peng ◽  
Yinying Xu ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Bombyx Mori ◽  
Sf9 Cells ◽  
Tissue Localization ◽  
Vitellogenin Receptor ◽  
Hemolymph Proteins ◽  
Female Specific ◽  
Oocyte Membrane ◽  
Silkworm Bombyx Mori

VgR, a member of the LDLR family, functions to transport vitellogenin into the ovaries to protome ovarian growth and embryonic development. In insects, the only widely accepted ligand of VgR is Vg. Recently, BmVgR has been shown to interact with BmSP1 in vitro. Therefore, in this study, we evaluated whether BmVgR could transport BmSP1 into certain cells. Although BmVgR could combine with BmVg and BmSP1, BmVgR did not affect the amount of BmSP1 taken up by Sf9 cells. Parallel immunofluorescence showed that most BmVg and BmVgR were localized in the inner oocyte membrane, showing tissue localization similar to that of BmVg labeled with pHrodo Red absorbed by the ovaries on day 2 of pupation. Although BmSP1 showed localization similar to BmVgR during the same phase, little BmSP1 was present in the ovary. Additionally, BmSP1 did not exist in ovaries when the ovaries contained BmVgR on day 5 of pupation, suggesting that BmSP1 in the ovaries was not endocytosed by BmVgR. In summary, BmVgR could facilitate uptake of BmVg by developing oocytes, but did not modulate in the transport of BmSP1.

scholarly journals Ecdysteroidogenesis in Heliothis virescens (Lepidoptera: Noctuidae): Recombinant Prothoracicotropic Hormone and Brain Extract Show Comparable Effects

2019 ◽  
Vol 19 (3) ◽  
Author(s):  
Marisa Nardiello ◽  
Rosanna Salvia ◽  
Andrea Scala ◽  
Carmen Scieuzo ◽  
Sabino Aurelio Bufo ◽  
...  
Keyword(s):  
Heliothis Virescens ◽  
Complex Mixture ◽  
Prothoracic Gland ◽  
Tobacco Budworm ◽  
Brain Extract ◽  
In Vitro Tests ◽  
Prothoracicotropic Hormone ◽  
Lepidoptera Noctuidae

Abstract Prothoracicotropic hormone (PTTH) is a neuropeptide that triggers a cascade of events within the prothoracic gland (PG) cells, leading to the activation of all the crucial enzymes involved in ecdysone biosynthesis, the main insect steroid hormone. Studies concerning ecdysteroidogenesis predicted PTTH action using brain extract (BE), consisting in a complex mixture in which some components positively or negatively interfere with PTTH-stimulated ecdysteroidogenesis. Consequently, the integration of these opposing factors in steroidogenic tissues leads to a complex secretory pattern. A recombinant form of prothoracicotropic hormone (rPTTH) from the tobacco budworm Heliothis virescens (F.) (Lepidoptera: Noctuidae) was expressed and purified to perform in vitro tests in a standard and repeatable manner. A characterization of rPTTH primary and secondary structures was performed. The ability of rPTTH and H. virescens BE to stimulate ecdysteroidogenesis was investigated on the third day of fifth larval stage. rPTTH activity was compared with the BE mixture by enzyme immunoassay and western blot, revealing that they equally stimulate the production of significant amount of ecdysone, through a transduction cascade that includes the TOR pathway, by the phosphorylation of 4E binding protein (4E-BP) and S6 kinase (S6K), the main targets of TOR protein. The results of these experiments suggest the importance of obtaining a functional pure hormone to perform further studies, not depending on the crude brain extract, composed by different elements and susceptible to different uncontrollable variables.

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