RIBOSOMAL-RNA PROCESSING - REMOVAL OF ONLY 19 BASES AT THE GAP BETWEEN 28S-ALPHA AND 28S-BETA RIBOSOMAL-RNAS IN SCIARA-COPROPHILA
RIBOSOMAL-RNA PROCESSING - REMOVAL OF ONLY 19 BASES AT THE GAP BETWEEN 28S-ALPHA AND 28S-BETA RIBOSOMAL-RNAS IN SCIARA-COPROPHILA
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DOI：
10.1093/nar/13.10.3581
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发表时间：
1985-01-01
影响因子：
14.9
通讯作者：
GERBI, SA
中科院分区：
文献类型：
--
作者：
WARE, VC;RENKAWITZ, R;GERBI, SA
本文测定了嗜尸石首菌（Sciara corprophila）28 S α和28 S β rRRA编码区之间的rDNA序列（称为“gap”），并利用S1核酸酶图谱和cDNA引物延伸技术确定了该差距的5′和3′端边界。在rDNA的差距区域发现的19个碱基是成熟的28 SrRNA所缺少的。真核rRNA含有大肠杆菌rRNA中不存在的一段核苷酸（“扩展片段”）。Sciarais中的差距区位于扩展节V内。因此，Sciaraap中19个碱基的切除表明扩展节V的大部分在成熟核糖体中不起作用。在Sciara和果蝇中保守的特定序列被认为是切除差距转录本的识别信号的候选者。
We have determined the sequence of the rDNA region between the 28Sα and 28Sβ rRRA coding segments (termed a “gap”) in the insectSciara corprophilaand have used S1 nuclease mapping and cDNA primer extension to define the 5′ and 3′ boundaries of the gap. Only 19 bases found in rDNA at the gap region are absent from mature 28S rRNA. Eukaryotic rRNAs contain stretches of nucleotides (“expansion segments”) which are absent inE.colirRNA. The gap region inSciarais located within expansion segment V. Therefore, the excision of 19 bases in theSciaragap suggests that a large portion of expansion segment V plays no function in mature ribosomes. Specific sequences conserved inSciaraandDrosophilaare considered as candidates for recognition signals for the excision of the gap transcript.