Corona Miguel, Velarde Rodrigo A, Remolina Silvia, Moran-Lauter Adrienne, Wang Ying, Hughes Kimberly A, Robinson Gene E
Department of Entomology, University of Illinois at Urbana-Champaign, 320 Morrill Hall, 505 South Goodwin Avenue, Urbana, IL 61801, USA.
Proc Natl Acad Sci U S A. 2007 Apr 24;104(17):7128-33. doi: 10.1073/pnas.0701909104. Epub 2007 Apr 16.
In most animals, longevity is achieved at the expense of fertility, but queen honey bees do not show this tradeoff. Queens are both long-lived and fertile, whereas workers, derived from the same genome, are both relatively short-lived and normally sterile. It has been suggested, on the basis of results from workers, that vitellogenin (Vg), best known as a yolk protein synthesized in the abdominal fat body, acts as an antioxidant to promote longevity in queen bees. We explored this hypothesis, as well as related roles of insulin-IGF-1 signaling and juvenile hormone. Vg was expressed in thorax and head fat body cells in an age-dependent manner, with old queens showing much higher expression than workers. In contrast, Vg expression in worker head was much lower. Queens also were more resistant to oxidative stress than workers. These results support the hypothesis that caste-specific differences in Vg expression are involved in queen longevity. Consistent with predictions from Drosophila, old queens had lower head expression of insulin-like peptide and its putative receptors than did old workers. Juvenile hormone affected the expression of Vg and insulin-IGF-1 signaling genes in opposite directions. These results suggest that conserved and species-specific mechanisms interact to regulate queen bee longevity without sacrificing fecundity.
在大多数动物中，长寿是以生育能力为代价实现的，但蜂王却不存在这种权衡。蜂王寿命长且能生育，而源自相同基因组的工蜂寿命相对较短且通常不育。基于对工蜂的研究结果，有人提出卵黄原蛋白（Vg），这种最知名的在腹部脂肪体中合成的卵黄蛋白，作为一种抗氧化剂促进蜂王的长寿。我们探究了这一假说以及胰岛素 - IGF - 1信号通路和保幼激素的相关作用。Vg在胸部和头部脂肪体细胞中呈年龄依赖性表达，老蜂王的表达量远高于工蜂。相比之下，工蜂头部的Vg表达量要低得多。蜂王对氧化应激的抵抗力也比工蜂更强。这些结果支持了这样的假说，即Vg表达的种姓特异性差异与蜂王的长寿有关。与果蝇的预测结果一致，老蜂王头部胰岛素样肽及其假定受体的表达量低于老工蜂。保幼激素对Vg和胰岛素 - IGF - 1信号通路基因的表达有相反的影响。这些结果表明，保守的和物种特异性的机制相互作用，在不牺牲繁殖力的情况下调节蜂王的寿命。
