| Literature DB >> 34449979 |
Sima Kazemi1, Rasoul Mirzaei1, Mohammad Sholeh2, Sajad Karampoor3,4, Fariba Keramat5, Massoud Saidijam6, Mohammad Yousef Alikhani1,5.
Abstract
INTRODUCTION: Human brucellosis is a zoonotic bacterial disease with up to 500,000 new cases each year. The major evasion mechanisms from the host immune system by Brucella are restraint of complement pathway and Toll-like receptors signaling pathways, interference with efficient antigen presentation to CD4-positive T lymphocytes, selective subversion of autophagy pathways, inhibition of dendritic cell stimulation, inhibition of autophagolysosomal fusion, and macrophage apoptosis. Many molecular and cellular pathways contribute to brucellosis that microRNAs have a vital function in the immunopathogenesis of this disease. In this regard, these molecules apply for their roles by modulating various events like inflammatory reactions and immune defense. Recently, in the case of immunity to human brucellosis, it has been shown that microRNAs play an important role in immunity against these bacteria. METHODS ANDEntities:
Keywords: biomarker; brucellosis; immunopathogenesis; microRNAs; therapeutic targets
Mesh:
Substances:
Year: 2021 PMID: 34449979 PMCID: PMC8589381 DOI: 10.1002/iid3.519
Source DB: PubMed Journal: Immun Inflamm Dis ISSN: 2050-4527
Figure 1The pathway of microRNA biogenesis. The miRNA is transcribed by RNA POL 2 to a pri‐miRNA. The pri‐miRNA cleavage is done by RNase III endonucleases Drosha and RNA binding protein, DGCR8 (overall so‐called microprocessor complex). This molecule is translocated from the nucleus by the Exportin5 (EXP5) binding RAN‐GTP. Once guanosine triphosphate (GTP) is hydrolyzed can liberate the pre‐miRNA molecule into the cell cytoplasm, which another RNase 3 type enzyme (Dicer) attaches the 5ʹ end of the pre‐miRNA molecule and cleaves the double‐stranded RNA. Twenty‐two nucleotides double‐stranded miRNA is recognized by AGO2 protein, and one strand is preferentially loaded into a miRISC that targets conserved the 5ʹ end of the miRNA named the seed sequence where they guide RISC to silence target mRNAs via mRNA cleavage, deadenylation as well as translational repression, whereas the passenger strands are degraded. PASHA, the microprocessor complex Drosha–DGCR8; AGO2, argonaute 2; miRNA, microRNA; RISC, RNA‐induced silencing complex
Figure 2Let7‐7f expression by Brucella inhibits the formation of NF‐κB formation. It has demonstrated that Brucella pathogens have a particular composition that increased the formation of Let7‐7f in human cells. NF‐κB, nuclear factor‐κB