title: Characterization of Argonaute2 gene from black tiger shrimp (Penaeus monodon) and its responses to immune challenges.
abstract: Argonaute2 binds to a short guide RNA (microRNA or short interfering RNA) and guides RNAs direct RISC to complementary mRNAs that are targets for RISC-mediated gene silencing. Here we identified and characterized Argonaute2 from black tiger shrimp Penaeus monodon (designated as PmAgo2). The full-length cDNA of PmAgo2 contained a 5' untranslated region (UTR) of 106 bp, an open reading frame (ORF) of 2616 bp and a 3' UTR of 123 bp. The predicted PmAgo2 protein is 99.4 KDa with the theoretical isoelectric point of 9.54. PmAgo2 shared the highest similarity of amino acid with Marsupenaeus japonicus Argonaute2 and Litopenaeus vannamei Argonaute2, at 69.0% and 68.5%, respectively. Phylogenic analysis showed PmAgo2 clustered with shrimp Argonaute2, and closed to the group of insects. Real-time quantitative PCR showed that PmAgo2 was widely expressed in almost all examined tissues except eyestalk, with high expression in lymph and haemocyte. mRNA expression also revealed that PmAgo2 was significantly up-regulated by Staphylococcus aureus and White Spot Syndrome Virus (WSSV) in hepatopancreas. Furthermore, our study also confirmed that dsRNA and ssRNA homologous poly (I:C) and R848 activated the expression of PmAgo2. The result indicated that PmAgo2 responded to both bacterial infection and viral infection, especially, it may induce an ssRNA-mediated RNAi with other core members of siRNA pathway in black tiger shrimp.
authors.affiliation: Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, The South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, PR China. Electronic address: lishi_yang@yahoo.com.
authors.forename: Lishi
authors.initials: L
authors.lastname: Yang
authors.affiliation: Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, The South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, PR China; College of Animal Science, South China Agriculture University, Guangzhou 510642, PR China.
authors.forename: Xiaolan
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, The South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, PR China.
authors.forename: Song
authors.initials: S
authors.lastname: Jiang
authors.affiliation: Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, The South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, PR China.
authors.forename: Lihua
authors.initials: L
authors.lastname: Qiu
authors.affiliation: Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, The South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, PR China.
authors.forename: Falin
authors.initials: F
authors.lastname: Zhou
authors.affiliation: Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, The South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, PR China.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Liu
authors.affiliation: Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, The South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, PR China. Electronic address: jiangsg@21cn.com.
authors.forename: Shigui
authors.initials: S
authors.lastname: Jiang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D060565:Argonaute Proteins / Q000235:genetics / Q000276:immunology*; D001483:Base Sequence; D003001:Cloning, Molecular; D043143:Hepatopancreas / Q000276:immunology*; D008969:Molecular Sequence Data; D033561:Penaeidae / Q000235:genetics / Q000276:immunology* / Q000382:microbiology / Q000821:virology; D010802:Phylogeny; D012313:RNA / Q000737:chemistry / Q000235:genetics; D011897:Random Allocation; D060888:Real-Time Polymerase Chain Reaction; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013211:Staphylococcus aureus / Q000276:immunology*; D046848:White spot syndrome virus 1 / Q000276:immunology*
chemical_list: D060565:Argonaute Proteins; D012313:RNA
keywords: Argonaute2; Bacteria; Penaeus monodon; RNAi pathway; Virus