Gene expression in relation to oogenesis, embryogenesis and development in Bombyx mori

利用家蚕的突变体及其假定的祖先家蚕分析了基因表达过程。1.卵壳绒毛膜是感兴趣的，因为它的复杂结构的形态发生编码的多基因家庭。扫描电子显微镜下观察到的黑腹蛛卵壳的最外层非常特异，这似乎与该物种的户外栖息地相匹配。桑卵绒毛膜含有桑卵中几乎没有的蛋白质成分。Southern印迹杂交分析表明，桑属和桑属的基因组DNA存在差异。因此，与家蚕相比，家蚕在绒膜位点可能具有不同的基因组。然而，就与最外层蛋白质相关的DNA而言，两个物种之间存在令人惊讶的同源性。可以合理地假设，外层在功能上是重要的，因为它与环境直接接触， ...更多信息 d相关序列在进化过程中是稳定的。需要进一步的分析，以揭示特定的外层结构是如何确定的。2.家蚕幼虫血淋巴中含有类胡萝卜素结合蛋白。以前已知缺乏血淋巴类胡萝卜素的突变体，有趣的是，证实该突变体也具有在许多生化特性方面与正常类胡萝卜素结合蛋白相同的蛋白质。结果表明，可能有，可能在中肠，一个遗传控制的机制下，类胡萝卜素分子窝藏到其特异性结合蛋白。3.蚕有许多突变体，其中卵的大小和样式都发生了改变。对其中一些突变体的形态学和生化分析表明，滤泡上皮细胞在决定卵性状方面起着关键作用。这些结果为理解卵子发生的复杂过程提供了一种方法。少

Gene expression processes were analyzed by using mutants of the domestic silkworm, Bombyx mori, as well as using its supposed ancestor Bombyx mandarina. 1. The eggshell chorion was of interest because of the morphogenesis of its complex structure coded for by the multigene families. Scanning electron microscopy of the mandarina eggshell was very specific at the outermost layer, which seemed to match the outdoor habitation of this species. The mandarina chorion had protein components which were scarcely detected in mori. Southern blot hybridization analysis of the genomic DNA of mandarina differed from those of mori. Thus, mandarina may have a distinct gene set at the chorion locus in comparison with the domestic silkworm. Nevertheless, with respect to the DNA related to the outermost layer proteins, there was a surprising homology between the two species. It may be reasonable to suppose that the outer layer is functionally important because of its direct contact with the environment an … More d the relevant sequences are stable during evolution. Further analysis of the mandarina genome is needed to uncover how the specific outer layer structure is determined. 2. The silkworm larvase were found to have a carotenoid binding protein in the haemolymph. Previously a mutant which lacks the hemolymph carotenoid has been known, interestingly, it was confirmed that the mutant also possesses the protein that was identical to the normal carotenoid binding protein in terms of many biochemical characteristics. The results suggested that there may be, probably in the midgut, a genetically controlled mechanism under which carotenoid molecules are harbored into their specific binding protein. 3. The silkworm has many mutants in which the size and pattern of the egg are modified. Morphological and biochemical analyses of some of such mutants revealed that the follicular epithelial cells have key roles in determining the egg characters. The results provide an approach to understanding the complex process of oogenesis. Less