The 30K proteins comprise about 35% of the total embryo yolk proteins and function as storage proteins during embryonic development of the domesticated silkworm Bombyx mori. The most abundant components of hemolymph are 30K proteins in the early and middle pupal stages. In the present study, the 30K protein BmLP7 was purified from larval hemolymph by chromatography. We prepared the antibody of this protein and found that it could bind to both BmLP3 and BmLP7. We used western blotting to analyze the dynamic change of BmLP3 and BmLP7 proteins in the hemolymph during development and found their concentration decreased dramatically from day 4 pupae, which appears to be linked to their accumulation in the oocyte for forming yolk granule since then. We found BmLP3 and BmLP7 proteins reduced significantly in day 10 eggs (the day before hatching). The crude extract of the newly hatched larvae showed proteolytic activity against BmLP3 and BmLP7 and immunohistochemistry showed BmLP3 and BmLP7 were degraded in the embryonic gut lumen in day 10 eggs. These systematic studies of BmLP3 and BmLP7 reveal their synthesis, transportation and degradation, which could represent the experience of all 30K proteins.

中文翻译：

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两种高度同源的家蚕30K蛋白BmLP3和BmLP7的合成，运输和降解。

30K蛋白约占总蛋黄蛋白的35％，并在家蚕Bombyx mori的胚胎发育过程中充当存储蛋白。血淋巴中最丰富的成分是p早期和中期的30K蛋白。在本研究中，通过色谱法从幼虫血淋巴中纯化了30K蛋白BmLP7。我们制备了该蛋白的抗体，发现它可以与BmLP3和BmLP7结合。我们使用蛋白质印迹法分析了发育过程中血淋巴中BmLP3和BmLP7蛋白的动态变化，发现它们的浓度从第4天p开始显着下降，此后似乎与它们在卵母细胞中的积累形成卵黄颗粒有关。我们发现BmLP3和BmLP7蛋白在第10天卵（孵化前一天）中显着降低。新孵化的幼虫的粗提物显示出对BmLP3和BmLP7的蛋白水解活性，免疫组织化学显示BmLP3和BmLP7在第10天卵的胚胎肠道内腔中被降解。对BmLP3和BmLP7的这些系统研究揭示了它们的合成，转运和降解，可以代表所有30K蛋白的经验。