miR-126-5p by direct targeting of JNK-interacting protein-2 (JIP-2) plays a key role in Theileria-infected macrophage virulence

Abstract

Theileria annulata is an apicomplexan parasite that infects and transforms bovine macrophages that disseminate throughout the animal causing a leukaemia-like disease called tropical theileriosis. Using deep RNAseq of T. annulata-infected B cells and macrophages we identify a set of microRNAs induced by infection, whose expression diminishes upon loss of the hyper-disseminating phenotype of virulent transformed macrophages. We describe how infection-induced upregulation of miR-126-5p ablates JIP-2 expression to release cytosolic JNK to translocate to the nucleus and trans-activate AP-1-driven transcription of mmp9 to promote tumour dissemination. In non-disseminating attenuated macrophages miR-126-5p levels drop, JIP-2 levels increase, JNK1 is retained in the cytosol leading to decreased c-Jun phosphorylation and dampened AP-1-driven mmp9 transcription. We show that variation in miR-126-5p levels depends on the tyrosine phosphorylation status of AGO2 that is regulated by Grb2-recruitment of PTP1B. In attenuated macrophages Grb2 levels drop resulting in less PTP1B recruitment, greater AGO2 phosphorylation, less miR-126-5p associated with AGO2 and a consequent rise in JIP-2 levels. Changes in miR-126-5p levels therefore, underpin both the virulent hyper-dissemination and the attenuated dissemination of T. annulata-infected macrophages.

Characterisation of infection associated microRNA and protein cargo in extracellular vesicles ofTheileria annulatainfected leukocytes

“…A recent publication (Haidar et al, 2018) described the miRNA of TBL20 and TBL3 cells relative to uninfected cells. A recent publication (Haidar et al, 2018) described the miRNA of TBL20 and TBL3 cells relative to uninfected cells.…”

“…However, the study of Haidar et al, demonstrated that a different miRNA, bta-miR126-5p, regulates MMP-9 expression; transfection of TBL20 cells with an inhibitor of a bta-miR126-5p decreased MMP-9 levels and reduced the capacity of the cells to migrate, while transfection with a mimic increased cell migration (Haidar et al, 2018). However, expression of the miR-181b mimic in TBL20 cells had no effect on MMP-9 FIGURE 7 miR-181a overexpression affects cell number in TBL20 cultures.…”

“…These expression patterns were conserved in TBL20 versus BL20 cells, indicating that in this case, the EV cargo largely reflects that of the host cell. A recent publication (Haidar et al, 2018) described the miRNA of TBL20 and TBL3 cells relative to uninfected cells.…”

“…Counts from wells containing TBL20 cells expressing miR-181a mimic or both mimics consistently and significantly showed decreased numbers (*p ≤ 0.05) expression, implying that under the conditions tested, MMP-9 is unlikely to be a true target of miR-181b. However, the study of Haidar et al, demonstrated that a different miRNA, bta-miR126-5p, regulates MMP-9 expression; transfection of TBL20 cells with an inhibitor of a bta-miR126-5p decreased MMP-9 levels and reduced the capacity of the cells to migrate, while transfection with a mimic increased cell migration (Haidar et al, 2018).…”

miR-34c-3p regulates PKA activity independent of cAMP via ablation of PRKAR2B inTheileria annulata-infected leukocytes

“…Apicomplexa manipulate their host cell's miRNomes to their own benefit (Cannella et al, 2014, Shapira et al, 2002, Zeiner et al, 2010. We have shown that miR-126-5p by directly targeting and suppressing JNK-Interacting-Protein JIP-2 liberates cytosolic JNK to translocate to the host cell nucleus and phosphorylate c-Jun that trans-activates AP-1-driven transcription of mmp9 to promote tumour dissemination of Theileria-transformed macrophages (Haidar et al, 2018).…”