Mounier N, Prudhomme J C
Biochimie. 1986 Sep;68(9):1053-61. doi: 10.1016/s0300-9084(86)80179-1.
To study the regulation of the gene(s) coding for the actin present in the microfilaments involved in the secretion of silk, we have probed a Bombyx mori genomic library with a Drosophila actin cDNA clone and selected 16 recombinant phages. They correspond to 3 different genomic fragments each containing a distinct actin coding sequence. Southern blots of genomic DNA probed with the cloned genes show that in Bombyx mori, there are at least 5 different actin genomic sequences. Two cloned genes A1 and A2 hybridize to a 1.7 kb long mRNA abundant in the carcass of the larva and thus probably code for muscle type actin. The third cloned gene, A3, hybridizes to two mRNAs of about 1.8 kb present in the silk gland and thus probably encodes a cytoplasmic actin. The coding sequence of this gene has been sequenced: it is almost identical to the Drosophila cytoplasmic actin genes but it has a single intron of 92 nucleotides within the codon 116, a position not observed in any other organism.
为了研究参与蚕丝分泌的微丝中肌动蛋白编码基因的调控，我们用果蝇肌动蛋白cDNA克隆探针筛选了家蚕基因组文库，挑选出16个重组噬菌体。它们对应于3个不同的基因组片段，每个片段都含有一个独特的肌动蛋白编码序列。用克隆基因探测基因组DNA的Southern印迹显示，在家蚕中至少有5种不同的肌动蛋白基因组序列。两个克隆基因A1和A2与幼虫体壁中丰富的1.7kb长的mRNA杂交，因此可能编码肌肉型肌动蛋白。第三个克隆基因A3与丝腺中存在的约1.8kb的两种mRNA杂交，因此可能编码一种细胞质肌动蛋白。该基因的编码序列已被测序：它与果蝇细胞质肌动蛋白基因几乎相同，但在密码子116内有一个92个核苷酸的单一内含子，这一位置在任何其他生物体中都未观察到。
