Sonobe Haruyuki, Odake Hiroshi
Department of Biology, Faculty of Science, Konan University, Higashinada-ku, 658, Kobe, Japan.
Rouxs Arch Dev Biol. 1986 May;195(4):229-235. doi: 10.1007/BF02438955.
Two-dimensional gel electrophoresis has been used to analyse patterns of proteins synthesized in the eggs from theBombyx mutantpnd, whose homozygous embryo never enters diapause owing to a genetic defect. At the middle to late stage of gastrulation the diapause type of the heterozygous embryo, derived from a homozygouspnd female mated to a wild-type male, synthesizes eight proteins which are not detected in the homozygouspnd embryo. To examine the relationship between embryonic diapause and the appearance of the heterozygote-specific proteins, the pattern of proteins synthesized in the heterozygotes of the diapause type was compared with that in heterozygotes which were artificially altered so that they would continue development. Only one of the eight heterozygote-specific proteins was constitutively synthesized according to the embryonic genome, irrespective of their developmental state, whereas appearance of the remaining seven proteins was exclusively dependent on their developmental nature. This finding strongly suggests that the unique protein might result from the expression of thepnd gene, and the other proteins might be synthesized along with diapause initiation in the heterozygotes. The possible role of the putativepnd gene-specific protein at the onset of embryonic diapause is discussed in relation to the action of the diapause factor, which predetermines embryonic diapause by affecting the developing oocytes.
二维凝胶电泳已被用于分析家蚕突变体pnd卵中合成的蛋白质模式，该突变体的纯合胚胎由于基因缺陷从未进入滞育。在原肠胚形成的中后期，由纯合pnd雌蚕与野生型雄蚕交配产生的杂合胚胎的滞育型会合成8种蛋白质，而在纯合pnd胚胎中未检测到这些蛋白质。为了研究胚胎滞育与杂合子特异性蛋白质出现之间的关系，将滞育型杂合子中合成的蛋白质模式与人工改变使其继续发育的杂合子中的蛋白质模式进行了比较。8种杂合子特异性蛋白质中只有一种是根据胚胎基因组组成性合成的，与它们的发育状态无关，而其余7种蛋白质的出现完全取决于它们的发育性质。这一发现强烈表明，这种独特的蛋白质可能是由pnd基因的表达产生的，而其他蛋白质可能是在杂合子滞育开始时一起合成的。本文讨论了假定的pnd基因特异性蛋白质在胚胎滞育开始时的可能作用，以及滞育因子的作用，滞育因子通过影响发育中的卵母细胞来预先决定胚胎滞育。
