农业虫鼠害综合治理研究国家重点实验室康乐研究组应用高通量测序的方法在飞蝗中发现了大量的small RNA。
研究人员通过与其它昆虫small RNA的比对发现了50种保守的miRNA， 并且发展了一种新的方法在没有基因组序列的前提下挖掘飞蝗特有的miRNA，发现了大约185种飞蝗特有的miRNA candidates。
本研究还阐述了miRNA*的保守性，以及昆虫miRNA的进化机制，大量的endo-siRNA以及piRNA也在飞蝗中鉴定出来。同时研究并发现飞蝗群散两型在small RNA的表达谱上面存在着巨大的差异，揭示了small RNA在飞蝗型变中可能起到的巨大作用。相关研究发表在《基因组生物学》（Genome Biology）杂志上。（生物谷Bioon.com）
生物谷推荐原始出处：
Genome Biology，doi:10.1186/gb-2009-10-1-r6，Yuanyuan Wei，Le Kang
Characterization and comparative profiling of the small RNA transcriptomes in two phases of locust
Yuanyuan Wei , Shuang Chen , Pengcheng Yang , Zongyuan Ma and Le Kang
State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Datun Road, Chaoyang District, Beijing 100101, PR China
Background
All the reports on insect small RNAs come from holometabolous insects whose genome sequence data are available. Therefore, study of hemimetabolous insect small RNAs could provide more insights into evolution and function of small RNAs in insects. The locust is an important, economically harmful hemimetabolous insect. Its phase changes, as a phenotypic plasticity, result from differential gene expression potentially regulated at both the post-transcriptional level, mediated by small RNAs, and the transcriptional level.
Results
Here, using high-throughput sequencing, we characterize the small RNA transcriptome in the locust. We identified 50 conserved microRNA families by similarity searching against miRBase, and a maximum of 185 potential locust-specific microRNA family candidates were identified using our newly developed method independent of locust genome sequence. We also demonstrate conservation of microRNA*, and evolutionary analysis of locust microRNAs indicates that the generation of miRNAs in locusts is concentrated along three phylogenetic tree branches: bilaterians, coelomates, and insects. Our study identified thousands of endogenous small interfering RNAs, some of which were of transposon origin, and also detected many Piwi-interacting RNA-like small RNAs. Comparison of small RNA expression patterns of the two phases showed that longer small RNAs were expressed more abundantly in the solitary phase and that each category of small RNAs exhibited different expression profiles between the two phases.
Conclusions
The abundance of small RNAs in the locust might indicate a long evolutionary history of post-transcriptional gene expression regulation, and differential expression of small RNAs between the two phases might further disclose the molecular mechanism of phase changes.
