蓖麻蚕18S rRNA基因3′末端的顺序特征

本文测定了蓖麻蚕18S rRNA基因(rDNA) 3′末端及其外侧的DNA顺序。将这一顺序与家蚕、果蝇、大鼠 18S rDNA 3′末端顺序以及大肠杆菌16 S rDNA 3′末端顺序作了比较,发现它们间有惊人的同源性。不仅如此,这些基因的3′末端所形成的茎环结构也十分相似,在3′末端还有保守的EcoRI切点。这些研究结果对了解18S rRNA 3′末端在蛋白质合成中的功能及在rRNA前体加工成熟中的作用;对于了解rRNA基因的进化打下了基础。

The Features of the 3' Terminal Sequences of the 18S rRNA-Gene from Silkworm Attacus ricini

The 3' terminal sequence of the gene for 18S rRNA of silkworm Anacus ricini have been sequenced.Comparison of this sequence with the 18S rDNA of silkworm Bombyx mori,Droso-phila melanogaster,rat and the 16S rDNA of E.coli has shown that there is a remarkable homo-logy between them.Moreover,the stem and loop formation of 3' regions of these rDNAs are very similar.There is a conservative EcoRI site in the 3' region of these rDNAs.These results may contribute to the understanding of the functions of the 3' end of 18S rDNA in protein synthesis,in proceeding of rRNA precursor,and to the understanding of the evolutionary relation of rDNAs.