RNase II: A new player enters the game
RNase II: A new player enters the game
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DOI：
10.1080/15476286.2015.1038013
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发表时间：
2015-04
期刊：
影响因子：
4.1
通讯作者：
Qingfeng Zhang;A. Scherf
中科院分区：
文献类型：
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作者：
Qingfeng Zhang;A. Scherf
疟疾是由疟原虫属的单细胞原生动物病原体引起的。虽然基因代表以生命周期阶段特异性方式表达的单顺反子单位，但在从脊椎动物宿主过渡到按蚊载体的寄生虫阶段中已观察到通过mRNA翻译抑制的转录后调节。最近在感染人类红细胞的恶性疟原虫阶段发现了一种有趣的新型转录后控制。一个被认为是转录沉默的基因亚组实际上是转录的，但被招募到这些基因位点的RNA酶II立即降解。这种隐藏的RNA在稳态RNA中是检测不到的，但已使用核运行技术和突变体RNase II寄生虫中检测到。新生RNA降解控制以单等位基因方式表达的毒力基因和非编码RNA（ncRNA），但也控制许多管家样基因。对其他生命周期阶段的更多研究可能会揭示疟疾寄生虫中这种类型的基因调控的全部范围。推测RNase II介导的基因控制可能存在于其他真核生物中是诱人的。
Malaria is caused by a unicellular protozoan pathogen of the genus Plasmodium. Although genes represent monocistronic units that are expressed in a life cycle stage-specific manner, post-transcriptional regulation via translational repression of mRNA has been observed in parasite stages that transition from the vertebrate host to the Anopheles vector. An interesting new type of post-transcriptional control was recently discovered in Plasmodium falciparum stages that infect human erythrocytes. A subgroup of genes that were thought to be transcriptionally silent are actually transcribed but degraded immediately by an RNase II that is recruited to these gene loci. This cryptic RNA is not detectable in steady-state RNA but has been detected using nuclear run-on techniques and in mutant RNase II parasites. Nascent RNA degradation controls virulence genes expressed in a monoallelic fashion and noncoding RNAs (ncRNAs), but also a number of housekeeping-like of genes. More studies on other life cycle stages may reveal the full extent of this type of gene regulation in malaria parasites. It is tempting to speculate that RNase II-mediated gene control may exist in other eukaryotic organisms.