The 5′ external transcribed spacer in mouse ribosomal RNA contains two cleavage sites
The 5′ external transcribed spacer in mouse ribosomal RNA contains two cleavage sites
复制标题
DOI：
10.1261/rna.1384709
复制
发表时间：
2009-01-01
期刊：
影响因子：
4.5
通讯作者：
Pestov, Dimitri G.
中科院分区：
文献类型：
--
作者：
Kent, Tatyana;Lapik, Yevgeniya R.;Pestov, Dimitri G.
5'外转录间隔区（5' ETS）是核糖体RNA转录物中最长的非编码区，对18 S rRNA的形成至关重要。在这里，我们表明，在小鼠5 'ETS加工涉及两个裂解事件。在位点A'的加工对应于先前描述的“初级切割”，其先于其它加工步骤。在新位点A0处的加工发生在A'下游1 kb处，产生两个新的rRNA前体：43 S和29 S。切除的5 '-A'和A '-A0片段在正常条件下迅速降解。外泌体组分EXOSC 10/PM-Scl 100（酵母Rrp 6p的直向同源物）的耗尽导致小鼠细胞中A '-A0间隔片段的强烈积累。我们讨论了在哺乳动物5 'ETS中发现的与U3 snoRNA参与pre-rRNA加工有关的第二加工位点，并提出了小鼠18 S rRNA加工途径的修订图。
The 5' external transcribed spacer (5'ETS) is critical for 18S rRNA formation and is the longest noncoding region in a ribosomal RNA transcript. Here we show that processing in mouse 5'ETS involves two cleavage events. Processing at site A' corresponds to the previously described "primary cleavage,'' which precedes other processing steps. Processing at the novel site A0 occurs 1 kb downstream from A' yielding two new rRNA precursors: 43S and 29S. The excised 5'-A' and A'-A0 fragments are rapidly degraded under normal conditions. Depletion of the exosome component EXOSC10/PM-Scl100 (ortholog of yeast Rrp6p) results in a strong accumulation of the A'-A0 spacer fragment in mouse cells. We discuss the finding of a second processing site in mammalian 5'ETS in relation to the involvement of the U3 snoRNA in pre-rRNA processing and present a revised map of the mouse 18S rRNA processing pathway.