Kageyama Y, Kinoshita T, Umesono Y, Hatakeyama M, Oishi K
Department of Biology, Faculty of Science, Kobe University, Japan.
Insect Biochem Mol Biol. 1994 Jun;24(6):599-605. doi: 10.1016/0965-1748(94)90096-5.
Athalia rosae (Hymenoptera) was previously shown to have two vitellins (L-Vn and S-Vn) and the two corresponding vitellogenins (L-Vg and S-Vg). A cDNA expression library was constructed from poly(A)+ RNA prepared from adult female fat body cells, and was screened for the vitellogenins by using antisera against the L- and S-Vn, respectively. Examinations of cloned cDNAs show that the vitellogenin gene is transcribed as a single unit, with the 5'-terminal site coding for the S-Vg and the 3'-terminal site for the L-Vg. Nucleotide sequence at the 5'-end suggests the presence of a 16 amino acid-long signal peptide. Deduced amino acid sequence following the signal peptide shows a complete match with up to the 28 N-terminal amino acid sequence determined on S-Vn. The S-L Vg boundary with deduced amino acid sequence matching with 6 N-terminal amino acid sequence determined on L-Vn is also detected. Northern blot hybridization analysis shows that the vitellogenin gene is expressed in the female fat body as a single 6.5 kb mRNA but not in the ovary, and not in the male fat body. Western blot analysis detects a large precursor polypeptide, reacting with the anti-L-Vn and S-Vn antisera, in the adult female fat body.
先前研究表明，玫瑰色三节叶蜂（膜翅目）含有两种卵黄磷蛋白（L-Vn和S-Vn）以及两种相应的卵黄原蛋白（L-Vg和S-Vg）。从成年雌性脂肪体细胞制备的聚腺苷酸加尾RNA构建了一个cDNA表达文库，分别使用针对L-Vn和S-Vn的抗血清筛选卵黄原蛋白。对克隆的cDNA进行检测发现，卵黄原蛋白基因作为一个单一单元转录，5'-末端位点编码S-Vg，3'-末端位点编码L-Vg。5'-末端的核苷酸序列表明存在一个16个氨基酸长的信号肽。信号肽之后推导的氨基酸序列与在S-Vn上确定的多达28个N-末端氨基酸序列完全匹配。还检测到推导的氨基酸序列与在L-Vn上确定的6个N-末端氨基酸序列匹配的S-L Vg边界。Northern印迹杂交分析表明，卵黄原蛋白基因在雌性脂肪体中以单一的6.5 kb mRNA形式表达，但在卵巢中不表达，在雄性脂肪体中也不表达。蛋白质免疫印迹分析在成年雌性脂肪体中检测到一种与抗L-Vn和S-Vn抗血清反应的大的前体多肽。
