Dataset Information

Regulation of macrophage gene expression by Mycobacterium tuberculosis: down-regulation of mitochondrial cytochrome c oxidase.

ABSTRACT: We have investigated changes in gene expression in mouse peritoneal macrophages following infection with virulent Mycobacterium tuberculosis. Using differential-display reverse transcription-PCR (RT-PCR), we have identified a gene that was markedly down-regulated within 6 h of infection and remained so for the duration of the experiment (5 days). On sequencing, this gene was found to encode the murine cytochrome c oxidase subunit VIIc (COX VIIc). Down-regulation of COX VIIc during M. tuberculosis infection was confirmed by three independent techniques: limiting-dilution RT-PCR, RNase protection assay, and Northern analysis. Limiting-dilution RT-PCR and Northern analysis were also used to analyze the specificity of this regulation; heat-killed M. tuberculosis, Mycobacterium bovis BCG, and latex beads had no effect on expression of COX VIIc. Down-regulation of this enzyme was also confirmed by using adherent cells isolated from spleens of M. tuberculosis-infected mice. These ex vivo macrophages showed apoptotic features, suggesting a possible involvement of cytochrome c oxidase in the programmed cell death of the host cells.

SUBMITTER: Ragno S

PROVIDER: S-EPMC108461 | biostudies-literature | 1998 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Regulation of macrophage gene expression by Mycobacterium tuberculosis: down-regulation of mitochondrial cytochrome c oxidase.

Ragno S S Estrada-Garcia I I Butler R R Colston M J MJ

Infection and immunity 19980801 8

We have investigated changes in gene expression in mouse peritoneal macrophages following infection with virulent Mycobacterium tuberculosis. Using differential-display reverse transcription-PCR (RT-PCR), we have identified a gene that was markedly down-regulated within 6 h of infection and remained so for the duration of the experiment (5 days). On sequencing, this gene was found to encode the murine cytochrome c oxidase subunit VIIc (COX VIIc). Down-regulation of COX VIIc during M. tuberculosi ...[more]

PMID: 9673285

Similar Datasets

Project description:Mycobacterium tuberculosis (M. tb) can survive in the hostile microenvironment of cells by escaping host surveillance, but the molecular mechanisms are far from being fully understood. MicroRNAs might be involved in regulation of this intracellular process. By RNAseq of M. tb-infected PMA-differentiated THP-1 macrophages, we previously discovered down-regulation of miR-378d during M. tb infection. This study aimed to investigate the roles of miR-378d in M. tb infection of THP-1 cells by using a miR-378d mimic and inhibitor. First, M. tb infection was confirmed to decrease miR-378d expression in THP-1 and Raw 264.7 macrophages. Then, it was demonstrated that miR-378d mimic promoted, while its inhibitor decreased, M. tb survival in THP-1 cells. Further, the miR-378d mimic suppressed, while its inhibitor enhanced the protein production of IL-1β, TNF-α, IL-6, and Rab10 expression. By using siRNA of Rab10 (siRab10) to knock-down the Rab10 gene in THP-1 with or without miR-378d inhibitor transfection, Rab10 was determined to be a miR-378d target during M. tb infection. In addition, a dual luciferase reporter assay with the Rab10 wild-type sequence and mutant for miR-378d binding sites confirmed Rab10 as the target of miR-378d associated with M. tb infection. The involvement of four signal pathways NF-κB, P38, JNK, and ERK in miR-378d regulation was determined by detecting the effect of their respective inhibitors on miR-378d expression, and miR-378d inhibitor on activation of these four signal pathways. As a result, activation of the NF-κB signaling pathway was associated with the down-regulation of miR-378d. In conclusion, during M. tb infection of macrophages, miR-378d was down-regulated and functioned on decreasing M. tb intracellular survival by targeting Rab10 and the process was regulated by activation of the NF-κB and induction of pro-inflammatory cytokines IL-1β, TNF-α, IL-6. These findings shed light on further understanding the defense mechanisms in macrophages against M. tb infection.

Dataset Information

Regulation of macrophage gene expression by Mycobacterium tuberculosis: down-regulation of mitochondrial cytochrome c oxidase.

Publications

Regulation of macrophage gene expression by Mycobacterium tuberculosis: down-regulation of mitochondrial cytochrome c oxidase.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets