Horard B, Bello B, Abraham E G, Coulon-Bublex M, Garel A, Mounier N
Université Lyon 1, Centre de Génétique Moléculaire et Cellulaire, Villeurbanne, France.
Insect Mol Biol. 1993;2(3):175-83. doi: 10.1111/j.1365-2583.1993.tb00137.x.
A cytoplasmic actin gene from Bombyx mori introduced into Drosophila melanogaster by P-element mediated transformation, is efficiently transcribed in larvae, pupae and adults of the host. The exogenous mRNA has the same size as the one observed in the Bombyx cells and the intron located within the coding region is properly excised, indicating a correct recognition of the exogenous sequences by the Drosophila transcriptional and splicing machineries. The expression of the Bombyx gene in Drosophila tissues was determined by transforming flies with a hybrid gene in which a large part of the Bombyx actin coding sequences was replaced by those of the bacterial lac Z gene. This chimaeric gene is specifically and highly expressed, from the embryo to the adult of the transgenic lines, in tissues of endodermal origin, the midgut and its derivatives, i.e. gastric caeca, the outer layer of the proventriculus, and in the Malpighian tubules. This gene is also expressed, at a lower level, in germ cells but restricted to the sixteen cell cysts during previtellogenesis. The expression of the Bombyx gene during development of transgenic flies was compared to that of the two Drosophila endogenous cytoplasmic actin genes and the results are discussed.
通过P因子介导的转化将家蚕的一个细胞质肌动蛋白基因导入黑腹果蝇，该基因在宿主的幼虫、蛹和成虫中能高效转录。外源mRNA的大小与在家蚕细胞中观察到的相同，并且位于编码区内的内含子能被正确切除，这表明果蝇的转录和剪接机制能够正确识别外源序列。通过用一个杂合基因转化果蝇来确定家蚕基因在果蝇组织中的表达情况，该杂合基因中家蚕肌动蛋白编码序列的很大一部分被细菌lacZ基因的序列所取代。这个嵌合基因在转基因品系从胚胎到成虫的整个发育过程中，在内胚层来源的组织、中肠及其衍生物（即胃盲囊、前胃的外层）以及马氏管中特异性且高水平地表达。该基因在生殖细胞中也有较低水平的表达，但仅限于卵黄发生前期的16细胞囊肿阶段。将转基因果蝇发育过程中家蚕基因的表达与黑腹果蝇两个内源性细胞质肌动蛋白基因的表达进行了比较，并对结果进行了讨论。
