《Nature》迄今最大的ncRNA

　　

生物通报道，霍华休斯医学院，耶鲁大学分子生物物理学和生物化学系，分子细胞与发育生物学系的科学家在最近的Nature上发表ncRNA研究的最新进展文章Exceptional structured noncoding RNAs revealed by bacterial metagenome analysis，为进一步探索RNA打下基础。

 

在耶鲁和霍华休斯医学院任职的Ronald R. Breaker教授是该文的通讯作者，主要从事RNA和DNA方面的研究，尤其是RNA酶和riboswitches方面的研究。

 

Ronald R. Breaker研究小组对从由海水样品提取出的物质进行了详细的计算机分析，研究发现，海水中存在有大量的DNA 和RNA，这些散落的核算物质被称为环境DNA或环境RNA。对这些核酸序列做计算分析，数据显示环境核酸中存在丰富的细菌非编码RNA（ncRNA），它们的大小与大型核糖酶相似，并且具有复杂的生物学结构。

 

令Ronald R. Breaker研究组特别感兴趣的是，在环境RNA的筛选过程中发现了两种新的RNA，它们分别被称为GOLLD 和 HEARO，据Ronald R. Breaker介绍这两种非编码RNA（ncRNA）是迄今所发现的最大、最复杂的RNA之一。

 

研究分析表明，这些复杂的RNA仅在水中、土壤中这些环境中被找到，并且具有超大的size以及复杂的结构，可能还存在一些为人们所不知的特性。研究者认为，这些ncRNA不仅存在水和土壤中，可能还存在于很多其他特殊的环境中，这都有待人们的进一步开采还研究。

 

这也许为人们更进一步了解RNA世界打下了基础。

非编码RNA，指的是不被翻译成蛋白质的RNA，如tRNA, rRNA等，这些RNA不被翻译成蛋白质，但是参与蛋白质翻译过程。

（生物通 小茜）

生物通推荐原文检索

Nature 462, 656-659 (3 December 2009) | doi:10.1038/nature08586; Received 20 July 2009; Accepted 15 October 2009

 

Exceptional structured noncoding RNAs revealed by bacterial metagenome analysis

Zasha Weinberg1,2, Jonathan Perreault2, Michelle M. Meyer2 & Ronald R. Breaker1,2,3

 

Howard Hughes Medical Institute,

Department of Molecular, Cellular and Developmental Biology,

Department of Molecular Biophysics and Biochemistry, Yale University, Box 208103, New Haven, Connecticut 06520-8103, USA

Correspondence to: Ronald R. Breaker1,2,3 Correspondence and requests for materials should be addressed to R.R.B. (Email: [e-mail]).

 

【Abstract】

Estimates of the total number of bacterial species1, 2, 3 indicate that existing DNA sequence databases carry only a tiny fraction of the total amount of DNA sequence space represented by this division of life. Indeed, environmental DNA samples have been shown to encode many previously unknown classes of proteins4 and RNAs5. Bioinformatics searches6, 7, 8, 9, 10 of genomic DNA from bacteria commonly identify new noncoding RNAs (ncRNAs)10, 11, 12 such as riboswitches13, 14. In rare instances, RNAs that exhibit more extensive sequence and structural conservation across a wide range of bacteria are encountered15, 16. Given that large structured RNAs are known to carry out complex biochemical functions such as protein synthesis and RNA processing reactions, identifying more RNAs of great size and intricate structure is likely to reveal additional biochemical functions that can be achieved by RNA. We applied an updated computational pipeline17 to discover ncRNAs that rival the known large ribozymes in size and structural complexity or that are among the most abundant RNAs in bacteria that encode them. These RNAs would have been difficult or impossible to detect without examining environmental DNA sequences, indicating that numerous RNAs with extraordinary size, structural complexity, or other exceptional characteristics remain to be discovered in unexplored sequence space.