MiR-146b-5p Plays a Critical Role in the Regulation of Autophagy in ∆per Brucella melitensis-Infected RAW264.7 Cells. (20th January 2020)

• Record Type: Journal Article
• Authors: Hanwei, Jiao; Nie, Xin; Zhu, Huapei; Li, Baobao; Pang, Feng; Yang, Xiaohong; Cao, Ruiyong; Yang, Xiaojian; Zhu, Shu; Peng, Dongmei; Li, Yaying; Li, Guohua; Zhang, Zhenxing; Huang, Haifeng; Xu, Kailian; Zhao, Tianjing; Cheng, Ying; Chen, Chuangfu; Du, Li; Wang, Fengyang
• Other Names: Gonzalez Juan E. Academic Editor.
• Is Part Of: BioMed research international. Volume 2020(2020)
• Publication Date: 2020-01-20
• Subjects: Medicine -- Periodicals; Biology -- Periodicals; Biotechnology -- Periodicals; Life sciences -- Periodicals; 610.5
• DOI: 10.1155/2020/1953242
• Languages: English
• ISSNs: 2314-6133

Abstract

Abstract : Brucella -caused brucellosis is one of the most widespread worldwide zoonoses. Lipopolysaccharide (LPS) of Brucella, which functions as pathogen-associated molecular patterns (PAMPs), is an important virulence factor that elicits protective antibodies. Per of B . melitensis is involved in the biosynthesis of the O-side chain of LPS. Autophagy is a crucial element of the innate immune response against intracellular pathogens including Brucella . In this study, we observed that autophagy was inhibited in RAW264.7 cells infected with Brucella melitensis ∆per. And, a high-throughput array-based screen and qRT-PCR validation were performed to identify the differentially expressed miRNAs in RAW264.7 cells infected with B. melitensis M5-90 ∆per. The results suggested that mmu-miR-146a-5p, mmu-miR-155-5p, mmu-miR-146b-5p, and mmu-miR-3473a were upregulated and mmu-miR-30c-5p was downregulated. During B. melitensis M5-90 ∆per infection, the increased expression of miR-146b-5p inhibited the autophagy activation in RAW264.7 cells. Using a bioinformatics approach, Tbc1d14 was predicted to be a potential target of miR-146b-5p . The results of a luciferase reporter assay indicated that miR-146b-5p directly targeted the 3′-UTR of Tbc1d14, and the interaction between miR-146b-5p and the 3′-UTR of Tbc1d14 was sequence-specific. High-throughput RNA-Seq-based screening was performed to identify differentially expressed genes in Tbc1d14-expressing RAW264.7 cells, and these were validated by qRT-PCR. Among the differentially expressed genes, four autophagy associated genes, IFNγ-inducible p47 GTPase 1 ( IIGP1 ), nuclear receptor binding protein 2 ( Nrbp2 ), transformation related protein 53 inducible nuclear protein 1 ( Trp53inp1 ), and immunity-related GTPase family M member 1 ( Irgm1 ), were obtained. Our findings provide important insights into the functional mechanism of LPS of B. melitensis .