Use of Bombyx mori Mutants to Study on Insect Biochemistry

Wells实验室从家蚕中肠分离到叶黄素结合蛋白（40kDa）。Fuji还从Y+^I家蚕的中肠中分离并鉴定了类胡萝卜素结合蛋白（600kDa）。该蛋白与血淋巴中的CBP具有相同的免疫学相似性和生化特性。YI家蚕的中肠中含有一种黄色蛋白，而Y+^I家蚕不含这种蛋白。颜色色素为类胡萝卜素。但该蛋白与抗cbp抗体不发生反应。因此，它是继CBP之后又一种新的类胡萝卜素结合蛋白。构建了Y+^I家蚕中肠cDNA文库。利用抗CBP抗体克隆了编码CBP的cDNA，获得了多个克隆。分析了两个克隆的核苷酸序列，但它们与CBP不相同。家蚕中肠和中蚕腺类胡萝卜素结合蛋白（CBP）的免疫细胞化学分析。免疫金技术显示CBP位于粗糙内质网和光滑内质网相关的小泡中。类胡萝卜素通过胞吐作用以类胡萝卜素结合CBP复合物的形式从中肠分泌到血淋巴中，以复合物的形式从血淋巴进入蚕丝中部，最终在丝氨酸颗粒排泄之前转移到丝胶中。从家蚕血淋巴中纯化了脂质转移颗粒（LTP）。LTP有三种载脂蛋白（占颗粒质量的79%）apoLTP - i,apoLTP=IInd apoLTP=III,Mr= 350000, 85000和60000。LTP的脂质为磷脂（54%）、单酰基甘油三醇（8.3%）、二酰基甘油（17%）、游离脂肪酸（14.3%）、三酰基甘油（5.9%）和烃（0.4%）。这种蛋白质能够催化多种脂质在不同脂质颗粒之间的转移。

Wells lab isolated lutein bound protein (40kDa) from the midgut of silkworm. Fuji also isolated and characterized carotinoid binding proitein (600kDa) from the midgut of the Y+^I silkworm. This protein is identical with CBP in hemolymph on the bisis of immunological similarity and the same biochemical properties as to CBP.The midgut of the YI silkworm contained a yellow colored protein, but did not in the Y+^I silkworm. The color pigment was carotinoid. But the protein did not react with anti-CBP antibody. Hence it is a new carotinoid binding protein other than CBP.cDNA library from the midgut of the Y+^I silkworm was constracted. cDNA encoding CBP has been cloned by using anti-CBP antibody and several clones were obtained. Two clones were analyzed nucleotide sequence, but they were not identical to CBP.Immunocytochemical analysis of carotinoid binding protein (CBP) in the midgut and middle silkgland of silkworm, Bombyx mori. Immunogold technique showed that CBP was located in rough ER,and in the small vesicle associated with smooth ER.Carotinoid was secreated into hemolymph from midgut as carotinoid bound CBP complex by exocytosis, incorporated into the middle part of silkgland from hemolymph as the complex and finally tansferrd to sericin prior to excretion of sericine particles.A lipid transfer particles (LTP) has been purified from the hemolymph of Bombyx mori. the LTP has three apoproteins (79% of particles mass) apo LTP-I,apoLTP=IInd apoLTP=III,Mr=350,000,85,000and 60,000. The lipid of LTP is phosphalipid (54%), monoacylgicerol (8.3%), diaacylglycerol (17%), free fatty acid (14.3%), triacylglycerol (5.9%) and hydrocarbon (0.4%).This protein is able to catalyze the transfer of a number of lipids among different lipid particle.