Evolution of Vault RNAs
Evolution of Vault RNAs
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DOI：
10.1093/molbev/msp112
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发表时间：
2009-09-01
影响因子：
10.7
通讯作者：
Ullmann, Kerstin
中科院分区：
文献类型：
--
作者：
Stadler, Peter F.;Chen, Julian J. -L.;Ullmann, Kerstin
金库RNA（VTRNA）很小，大约100 nt长的聚合酶III转录本包含在真核细胞的金库颗粒中。大概是由于其神秘的功能，与大多数其他非编码RNA（NCRNA）家族相比，它们几乎没有受到关注。他们的序列保守性不佳使同源性搜索甚至在脊椎动物中也是复杂而繁琐的任务。在这里，我们报告了对依育抑制剂中这种快速发展的NCRNA类别的系统和全面分析，从而提供了全面的计算预测VTRNA基因的集合。我们发现，所有先前描述的VTRNA都位于与原钙粘蛋白基因簇相关的保守基因组基因座，该基因群是在整个gnathostomes中保守的缔合。在该区域经常观察到对小VTRNA基因簇的谱系特异性扩展。第二个vtrna基因座在eutherian哺乳动物中同步保守。两个Eutherian基因座的VTRNA在其启动子结构上表现出很大的差异，从而解释了其在几种人类癌细胞系中的差异表达模式。在硬骨鱼中，通过逆转录酶 - 聚合酶链反应验证了几种寄生虫VTRNA基因的表达，大多数但并非全部位于同步保守的原始钙粘着蛋白基因座。
Vault RNAs (vtRNAs) are small, about 100 nt long, polymerase III transcripts contained in the vault particles of eukaryotic cells. Presumably due to their enigmatic function, they have received little attention compared with most other noncoding RNA (ncRNA) families. Their poor sequence conservation makes homology search a complex and tedious task even within vertebrates. Here we report on a systematic and comprehensive analysis of this rapidly evolving class of ncRNAs in deuterostomes, providing a comprehensive collection of computationally predicted vtRNA genes. We find that all previously described vtRNAs are located at a conserved genomic locus linked to the protocadherin gene cluster, an association that is conserved throughout gnathostomes. Lineage-specific expansions to small vtRNA gene clusters are frequently observed in this region. A second vtRNA locus is syntenically conserved across eutherian mammals. The vtRNAs at the two eutherian loci exhibit substantial differences in their promoter structures, explaining their differential expression patterns in several human cancer cell lines. In teleosts, expression of several paralogous vtRNA genes, most but not all located at the syntenically conserved protocadherin locus, was verified by reverse transcriptase-polymerase chain reaction.