Comas D, Piulachs M D, Bellés X
Department of Physiology and Molecular Biodiversity, Institut de Biologia Molecular de Barcelona (CID, CSIC), J. Girona 18, 08034 Barcelona, Spain.
Mol Cell Endocrinol. 2001 Oct 25;183(1-2):93-100. doi: 10.1016/s0303-7207(01)00589-5.
In the cockroach Blattella germanica, the synthesis of vitellogenin is juvenile hormone III (JH III)-dependent. We have studied the effect of JH III upon vitellogenin gene expression in periovaric fat bodies incubated in vitro. Periovaric fat bodies were obtained from cardioallatectomized females. The response to JH III was measured in terms of vitellogenin and vitellogenin mRNA after 7 h of incubation. A hormonal concentration as low as 1 nM was enough to induce vitellogenin production and its release to the medium, whereas the concentration of 10 nM produced the maximal effects. Although the response of the vitellogenin gene to JH III is fast and efficient, it seems that the action is mediated by protein factors, given that cycloheximide treatment impairs the hormonal effect. The presence in the medium of brain extract (0.5 equivalents), corpora cardiaca (one pair) or hypertrehalosemic hormone (10(-7) or 10(-8) M), partially inhibited the response to JH III.
在德国小蠊中，卵黄原蛋白的合成依赖于保幼激素III（JH III）。我们研究了JH III对体外培养的卵巢周围脂肪体中卵黄原蛋白基因表达的影响。卵巢周围脂肪体取自心侧体切除的雌性个体。在培养7小时后，根据卵黄原蛋白和卵黄原蛋白mRNA来测定对JH III的反应。低至1 nM的激素浓度就足以诱导卵黄原蛋白的产生并将其释放到培养基中，而10 nM的浓度产生最大效应。尽管卵黄原蛋白基因对JH III的反应迅速且有效，但鉴于环己酰亚胺处理会削弱激素效应，其作用似乎是由蛋白质因子介导的。培养基中存在脑提取物（0.5当量）、心侧体（一对）或高海藻糖血症激素（10⁻⁷或10⁻⁸ M）会部分抑制对JH III的反应。
