Vitellogenin (Vg) plays a vital role in the reproduction of oviparous species, as the precursor of the major egg storage protein. In bees, most of the studies of this protein rely on honey bees (Apis mellifera), and very little is known in solitary species. The solitary bees Centris tarsata and C. analis were chosen to characterize vg cDNA and better understand its expression. The Vg-deduced amino acid sequences from these bees have typical Vg features found in other hymenopterans. Besides its main site of synthesis, the fat body, transcripts of vg were also observed in ovaries. Males also showed expression of vg, although in lower levels compared with females. During development, vg expression was observed in late larvae, pupae, and female adults. The highest amounts of vg transcripts were observed in egg-laying females. Expression of vg increased rapidly in a few hours after female adult emergence, which indicates that its gene expression does not depend on mating to be triggered.

中文翻译：

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孤蜂 Centris tarsata 和 Centris analis（膜翅目：蜂科）的卵黄蛋白原：cDNA 结构分析和基因表达

卵黄蛋白原 (Vg) 作为主要卵储存蛋白的前体，在卵生物种的繁殖中起着至关重要的作用。在蜜蜂中，对这种蛋白质的大部分研究都依赖于蜜蜂（Apis mellifera），而在独居物种中知之甚少。选择孤蜂 Centris tarsata 和 C. analis 来表征 vg cDNA 并更好地了解其表达。这些蜜蜂的 Vg 推导的氨基酸序列具有在其他膜翅目昆虫中发现的典型 Vg 特征。除了它的主要合成部位，脂肪体之外，在卵巢中也观察到了 vg 的转录本。男性也表现出 vg 的表达，尽管与女性相比水平较低。在发育过程中，在晚期幼虫、蛹和雌性成虫中观察到 vg 表达。在产卵雌性中观察到最高数量的 vg 转录物。