Thursday, December 19, 2013

STAT3-dependent transactivation of mirna genes following Toxoplasma gondii infection in macrophage

 2013 Dec 16;6(1):356. [Epub ahead of print]

STAT3-dependent transactivation of mirna genes following Toxoplasma gondii infection in macrophage

Abstract

BACKGROUND:

The apicomplexan parasite Toxoplasma gondii can infect and replicate in virtually any nucleated cell in many species of warm-blooded animals; T. gondii has elaborate mechanisms to counteract host-cell apoptosis in order to maintain survival and breed in the host cells.

METHODS:

Using microarray profiling and a combination of conventional molecular approaches, we investigated the levels of microRNAs (miRNAs ) in human macrophage during T. gondii infection. We used molecular tools to examine Toxoplasma-upregualted miRNAs to revealed potential signal transducers and activators of transcription 3( STAT3) binding sites in the promoter elements of a subset of miRNA genes. We analysed the apoptosis of human macrophage with the functional inhibition of the STAT3-binding miRNAs by flow cytometry.

RESULTS:

Our results demonstrated differential alterations in the mature miRNA expression profile in human macrophage following T. gondii infection. Database analysis of Toxoplasma-upregulated miRNAs revealed potential STAT3 binding sites in the promoter elements of a subset of miRNA genes. We demonstrated that miR-30c-1, miR-125b-2, miR-23b-27b-24-1 and miR-17 ~ 92 cluster genes were transactivated through promoter binding of the STAT3 following T. gondii infection. Importantly, functional inhibition of selected STAT3-binding miRNAs in human macropahges increased apoptosis of host cells.

CONCLUSIONS:

A panel of miRNAs is regulated through promoter binding of the STAT3 in human macrophage and these miRNAs are involved in anti-apoptosis in response to T. gondii infection.
PMID:
 
24341525
 
[PubMed - as supplied by publisher]

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