Environmental RNAi in herbivorous insects.
Environmental RNAi in herbivorous insects.
复制标题
DOI：
10.1261/rna.048116.114
复制
发表时间：
2015-05
期刊：
影响因子：
--
通讯作者：
Heck GR
中科院分区：
文献类型：
--
作者：
Ivashuta S;Zhang Y;Wiggins BE;Ramaseshadri P;Segers GC;Johnson S;Meyer SE;Kerstetter RA;McNulty BC;Bolognesi R;Heck GR
环境RNAi(Ernai)是外源双链RNA(DsRNA)对内源基因表达的一种序列特异性调控。虽然在人工饲料条件下和通过转基因植物在几种草食昆虫中证明了这一点，但在自然昆虫生活条件下，外源dsRNA摄取的大小和结果以及ernai的作用尚不清楚。我们对取食野生型植物的对二奈敏感的鞘翅目昆虫的分析表明，它们吸收了植物内源的长dsRNAs，而不是小RNAs。随后，dsRNAs被昆虫加工成21个核苷酸的siRNA，并在昆虫细胞中大量积累。在对二奶抗性的鳞翅目昆虫幼虫体内，没有观察到寄主植物来源的siRNAs的积累。鞘翅目幼虫肠道中摄取的dsRNA的稳定性以及从肠道摄取和运输到远端组织的过程似乎是Ernai的促成因素。尽管有大量不同的鞘翅目昆虫来源的植物来源的siRNAs与昆虫转录产物具有序列互补性，但绝大多数siRNAs的丰度相对较低，RNA-seq分析没有检测到植物来源的siRNAs对昆虫转录组的显著影响。综上所述，我们观察到在自然取食条件下，在Ernai敏感的昆虫中，植物内源dsRNA在全基因组范围内被广泛吸收，并随后将摄入的dsRNA加工成21个核苷酸的siRNA。除了肠道中dsRNA的稳定性和摄取外，针对给定昆虫转录本的siRNAs的剂量可能是一个重要因素，以便在缺乏明显沉默扩增机制的Ernai胜任昆虫中实现可测量的基于Ernai的调节。
Environmental RNAi (eRNAi) is a sequence-specific regulation of endogenous gene expression in a receptive organism by exogenous double-stranded RNA (dsRNA). Although demonstrated under artificial dietary conditions and via transgenic plant presentations in several herbivorous insects, the magnitude and consequence of exogenous dsRNA uptake and the role of eRNAi remains unknown under natural insect living conditions. Our analysis of coleopteran insects sensitive to eRNAi fed on wild-type plants revealed uptake of plant endogenous long dsRNAs, but not small RNAs. Subsequently, the dsRNAs were processed into 21 nt siRNAs by insects and accumulated in high quantities in insect cells. No accumulation of host plant-derived siRNAs was observed in lepidopteran larvae that are recalcitrant to eRNAi. Stability of ingested dsRNA in coleopteran larval gut followed by uptake and transport from the gut to distal tissues appeared to be enabling factors for eRNAi. Although a relatively large number of distinct coleopteran insect-processed plant-derived siRNAs had sequence complementarity to insect transcripts, the vast majority of the siRNAs were present in relatively low abundance, and RNA-seq analysis did not detect a significant effect of plant-derived siRNAs on insect transcriptome. In summary, we observed a broad genome-wide uptake of plant endogenous dsRNA and subsequent processing of ingested dsRNA into 21 nt siRNAs in eRNAi-sensitive insects under natural feeding conditions. In addition to dsRNA stability in gut lumen and uptake, dosage of siRNAs targeting a given insect transcript is likely an important factor in order to achieve measurable eRNAi-based regulation in eRNAi-competent insects that lack an apparent silencing amplification mechanism.
登录
查看更多内容
DOI：
10.1093/bioinformatics/btu638
发表时间：
2015-01-15
期刊：
Bioinformatics (Oxford, England)
影响因子：
--
作者：
Anders S;Pyl PT;Huber W
通讯作者：
Huber W
影响因子：
12.3
作者：
Tomoyasu Y;Miller SC;Tomita S;Schoppmeier M;Grossmann D;Bucher G
通讯作者：
Bucher G
影响因子：
16
作者：
McEwan, Deborah L.;Weisman, Alexandra S.;Huntert, Craig P.
通讯作者：
Huntert, Craig P.
影响因子：
4.4
作者：
Zhang Y;Wiggins BE;Lawrence C;Petrick J;Ivashuta S;Heck G
通讯作者：
Heck G
影响因子：
4.3
作者：
Ivashuta, Sergey I.;Petrick, Jay S.;Roberts, James K.
通讯作者：
Roberts, James K.