title: RNAi suppression of zebrafish peptidoglycan recognition protein 6 (zfPGRP6) mediated differentially expressed genes involved in Toll-like receptor signaling pathway and caused increased susceptibility to Flavobacterium columnare.
abstract: In Drosophila, Toll signaling cascade, which resembles the mammalian Toll-like receptor (TLR)/IL-1R signaling pathways and regulates the expression of anti-microbial peptide genes, mainly relies on peptidoglycan recognition proteins (PGRPs) for the detection of bacterial pathogens. To explore the effect of zebrafish peptidoglycan recognition protein 6 (zfPGRP6) on Toll-like receptor signaling pathway, RNA interference (siRNA) and real time quantitative PCR (RQ-PCR) methods were used to identify differentially expressed genes regulated by zfPGRP6. The target genes included TLR2, TLR3, TLR5, TLR7, TLR8, IL1R, Sterile-alpha and Armadillo motif containing protein (SARM), myeloid differentiation factor 88 (MyD88) and nuclear factor (NF)-kappa B2 (p100/p52). The results of RQ-PCR showed that RNAi-mediated suppression of zfPGRP6 significantly down-regulated the expression of TLR2, TLR5, IL1R, SARM, MyD88 and p100/p52. The expression of beta-defensin-1 was also down-regulated in those embryos silenced by zfPGRP6. In challenge experiments to determine the anti-bacterial response to Gram-negative bacteria, RNAi knock-down of zfPGRP6 markedly increased susceptibility to Flavobacterium columnare.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, and Laboratory of Fish Diseases, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province 430072, PR China.
authors.forename: M X
authors.initials: MX
authors.lastname: Chang
authors.forename: P
authors.initials: P
authors.lastname: Nie
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000276:immunology; D004247:DNA / Q000737:chemistry / Q000235:genetics; D045826:Flavobacteriaceae Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D005417:Flavobacterium / Q000276:immunology*; D020868:Gene Silencing; D053582:Interleukin-1alpha / Q000737:chemistry / Q000235:genetics; D053594:Myeloid Differentiation Factor 88 / Q000737:chemistry / Q000235:genetics; D016328:NF-kappa B / Q000737:chemistry / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000662:veterinary; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D015398:Signal Transduction; D051193:Toll-Like Receptors / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D015027:Zebrafish / Q000235:genetics / Q000276:immunology*; D023083:beta-Defensins / Q000737:chemistry / Q000235:genetics
chemical_list: D002352:Carrier Proteins; D053582:Interleukin-1alpha; D053594:Myeloid Differentiation Factor 88; D016328:NF-kappa B; D034741:RNA, Small Interfering; D051193:Toll-Like Receptors; D023083:beta-Defensins; C118897:peptidoglycan recognition protein; D004247:DNA