Genetics and Biotechnology Unit, Central Institute of Brackishwater Aquaculture, 75 Santhome High Road, R.A Puram, Chennai, India.
Genetics and Biotechnology Unit, Central Institute of Brackishwater Aquaculture, 75 Santhome High Road, R.A Puram, Chennai, India.
Fish Shellfish Immunol. 2019 Oct;93:288-295. doi: 10.1016/j.fsi.2019.07.057. Epub 2019 Jul 19.
In recent years, the importance of viral and host microRNAs (miRNAs) in mediating viral replication and control of host cellular machinery, has been realised and increasing efforts have been taken in order to understand the interactions of miRNAs from host and pathogen during infection. However, all existing studies has thus far been conducted in controlled experimental conditions and the veracity of these data for field conditions are yet to be established. In this framework, small RNA sequencing was performed to identify the miRNAs involved in shrimp (Penaeus vannamei) immune responses under two different WSSV infection conditions of natural infection and experimentally challenged conditions. The expression profiles of miRNAs of shrimp infected with WSSV under two contrasting conditions were compared and as a result, 23365 known miRNAs and 481 novel miRNAs were identified. Amongst the most abundantly expressed miRNAs, the hypoxia related miR-210 and immune pathway related miR-29b were expressed only in infected shrimps of both conditions. miR-8-5p, having a functional role in modulation of chitin biosynthesis was exclusively represented in higher numbers in the WSSV -infected shrimps under natural conditions whilst four of the miRNAs (mja-miR-6493-5p, mja-miR-6492, mmu-miR-3968, tcf-miR-9b-5p) identified from shrimps collected from pond culture targeted chitinase, an important enzyme involved in growth and moulting in shrimps, indicating an interaction between WSSV infection and moult cycle under culture conditions. Some of the miRNAs (tca-miR-87b-3p, cte-miR-277a) and miRNAs belonging to class miR-9, miR-981 that were identified only in WSSV infected shrimps under experimental conditions, are known to respond against WSSV infection in shrimps. Moreover, the miRNA target prediction revealed several immune-related gene targets such as cathepsin, c-type lectin, haemocyanin and ubiquitin protein ligase were commonly identified under both the conditions. However, the miRNAs identified from challenge experiment had wide number of gene targets as compared to the miRNAs of natural infection. The shrimp miRNA mja-miR-6489-3p, was also found to target early virus gene wsv001 of WSSV. Our study, therefore, provides the comparative analysis of miRNA expression from shrimp during WSSV infection in two different conditions.
近年来，病毒和宿主 microRNAs（miRNAs）在介导病毒复制和宿主细胞机制调控中的重要性已被认识到，并且为了理解感染过程中宿主和病原体的 miRNAs 相互作用，人们已经做出了越来越多的努力。然而，到目前为止，所有现有的研究都是在受控的实验条件下进行的，这些数据在野外条件下的准确性尚未得到证实。在这个框架内，进行了小 RNA 测序，以鉴定在两种不同的 WSSV 感染条件下，即自然感染和实验性挑战条件下，参与虾（Penaeus vannamei）免疫反应的 miRNAs。比较了在两种对照条件下感染 WSSV 的虾的 miRNAs 表达谱，结果鉴定了 23365 个已知 miRNAs 和 481 个新 miRNAs。在表达最丰富的 miRNAs 中，与缺氧相关的 miR-210 和与免疫途径相关的 miR-29b 仅在两种条件下的感染虾中表达。miR-8-5p 在甲壳素生物合成的调节中具有功能作用，仅在自然条件下感染 WSSV 的虾中以更高的数量代表，而从池塘养殖中采集的虾中鉴定出的 4 个 miRNAs（mja-miR-6493-5p、mja-miR-6492、mmu-miR-3968、tcf-miR-9b-5p）靶向甲壳质酶，这是一种在虾生长和蜕皮中起重要作用的酶，表明在养殖条件下 WSSV 感染和蜕皮周期之间存在相互作用。在实验条件下仅在感染 WSSV 的虾中鉴定出的一些 miRNAs（tca-miR-87b-3p、cte-miR-277a）和属于 miR-9、miR-981 类的 miRNAs 已知在虾中对 WSSV 感染有反应。此外，miRNA 靶标预测显示，在两种条件下，几种免疫相关基因靶标如组织蛋白酶、C 型凝集素、血蓝蛋白和泛素蛋白连接酶都被共同鉴定出来。然而，与自然感染的 miRNAs 相比，从挑战实验中鉴定出的 miRNAs 有更多数量的基因靶标。虾 miRNA mja-miR-6489-3p 也被发现靶向 WSSV 的早期病毒基因 wsv001。因此，我们的研究提供了在两种不同条件下虾在 WSSV 感染期间 miRNA 表达的比较分析。
