Pho D B, Pennanec'h M, Jallon J M
Laboratoire des Mécanismes de Communication, CNRS URA 1491, Université de Paris-Sud, Orsay, France.
Arch Insect Biochem Physiol. 1996;31(3):289-303. doi: 10.1002/(SICI)1520-6327(1996)31:3<289::AID-ARCH4>3.0.CO;2-T.
Lipophorin was isolated from homogenized adult Drosophila melanogaster. It is stained by Sudan Black and has a native molecular mass of 640 kD and a density of 1.12 g/ml. It consists of two glycosylated apoproteins of 240 and 75 kDa. Gas chromatography and mass spectrometry showed that lipophorins isolated separately from virgin 3-day-old male and female flies were associated with specific hydrocarbons, and that these were the same hydrocarbons found in male and female cuticles, respectively. Moreover, a pool of internal hydrocarbons was demonstrated for the first time, with chain lengths similar to those of the cuticular pool. Studies on the fate of the hydrocarbons synthesized de novo after topical applications of radiolabelled fatty acid precursors showed a decrease of the internal pool of hydrocarbons with time, concomitant with an increase of the cuticular pool. These results suggest that hydrocarbons synthesized at an internal site, possibly in oenocytes, may be transported to the cuticle of the flies by lipophorin.
脂动蛋白是从成年黑腹果蝇匀浆中分离出来的。它可被苏丹黑染色，天然分子量为640 kD，密度为1.12 g/ml。它由两种糖基化载脂蛋白组成，分子量分别为240 kDa和75 kDa。气相色谱和质谱分析表明，从3日龄未交配的雄蝇和雌蝇中分别分离出的脂动蛋白与特定的碳氢化合物有关，且这些碳氢化合物分别与雄蝇和雌蝇表皮中的碳氢化合物相同。此外，首次证实存在一组内部碳氢化合物，其链长与表皮中的碳氢化合物池相似。对放射性标记脂肪酸前体局部应用后新合成的碳氢化合物命运的研究表明，随着时间的推移，内部碳氢化合物池减少，同时表皮碳氢化合物池增加。这些结果表明，可能在内皮细胞中在内部位点合成的碳氢化合物可能通过脂动蛋白转运到果蝇的表皮。
