RNA interference in shrimp and potential applications in aquaculture

Abstract

As the RNA interference mechanism was discovered, researchers have made huge strides in unravelling biological mechanisms at the gene level in a wide range of organisms. RNAi is a simple and rapid method that allows silencing gene expression at the post-transcriptional level and is triggered by the introduction of double-stranded RNA into the cell, leading to the degradation of the corresponding mRNA. In this review, we will provide an overview of successful RNAi experiments to date in Crustacea, and shrimp in particular, with special focus on various potential applications of RNA interference in research and aquaculture. An important aspect of RNAi in any species is the delivery of the double-stranded RNA and the barriers that have to be overcome to get the dsRNA into the target cells. Different options, experimental procedures, success rates and challenges in using RNAi are discussed in this review

Assessment of the Effects of Double-Stranded RNAs Corresponding to Multiple Vitellogenesis-Inhibiting Hormone Subtype I Peptides in Subadult Female Whiteleg Shrimp, Litopenaeus vannamei

“…Evidence of such a phenomenon was reported in arthropods, specifically in insects [for example, the African malaria mosquito ( 23 )], and as well was observed in shrimp as detailed in this study. Transcriptional silencing generally occurs through long-dsRNA (>200 bp), which is processed into short interfering RNAs (siRNA of 20–30 bp) by endogenous Dicer (an RNase-III-like enzyme) in cells; the resultant siRNA represses transcription of the target gene ( 24 , 25 ). Therefore, the endogenously produced siRNA may disrupt the expression of homologous genes with short-matched sequences.…”

“…Nevertheless, there were no large differences in oocyte development among the various treatments, but there did seem to be more early-stage endogenous vitellogenic oocytes in the mixed-dsRNA group at 10 days as shown in Figure 4E-1 . On the other hand, RNAi techniques using dsRNA have been used to increase immunity in shrimps; injection of dsRNA for non-specific genes improved the survival of diseased shrimp affected with white spot syndrome virus ( 25 , 30 ). In our case, injection of GFP-dsRNA may have eventually improved shrimp health conditions in L. vannamei .…”

The role of shrimp microRNAs in immune response and beyond

“…The presence of the microRNA biogenesis pathway in penaeid shrimp has been described (Nguyen et al 2016), indicating the expression of key components from this biological pathway. In Penaeus monodon, DNA constructs that expressed long-hairpin RNA constitutively against two White Spot Syndrome Virus (WSSV) envelop genes conferred protection upon pathogen infection, which indirectly suggest a functional microRNA pathway (Krishnan et al 2009).…”

A genome-wide screening for RNAi pathway proteins in Acari

“…The experimental application of RNAi for gene silencing in arthropods including Acari exploits the siRNA pathway, which is activated mainly via the exogenous administration of specific synthetic dsRNAs [12,13,[23][24][25]. In principle, three molecular processes are expected to define the success of gene silencing: the uptake of dsRNA by the target cell, the amplification of the siRNAs and the transport of the latter to distant cells to induce gene silencing throughout the treated organism, a phenomenon referred to as systemic RNAi [23].…”