Actin-binding protein regulation by microRNAs as a novel microbial strategy to modulate phagocytosis by host cells: the case of N-Wasp and miR-142-3p

Frontiers in Cellular and Infection Microbiology

Vladimir eBenes¹  Jonathon eBlake¹  Nuno eCarmo²  Elsa eAnes²  Leonor eSantos²  Paulo eBettencourt²  David ePires²  Sabrina eMarion³  Claire eLastrucci⁴  Geanncarlo eLugo-Villarino⁴  Olivier eNeyrolles⁴  Gareth eGriffiths⁵ 

[1] European Molecular Biology Laboratory;Faculdade de Farmácia, Universidade de Lisboa;INSERM U 1016, CNRS UMR 8104, Université Paris Descartes, Paris, France.;Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, Université Paul Sabatier, Toulouse, France;University of Oslo, PO Box 1041, Blindern, 0316 Oslo, Norway;

关键词: Phagocytosis;    Tuberculosis;    miRNA;    macrophage;    mir-142-3p;    N-Wasp;   

DOI  :  10.3389/fcimb.2013.00019

来源: DOAJ

【 摘 要 】

Mycobacterium tuberculosis (Mtb) is a successful intracellular pathogen that thrives in macrophages (Mφs). There is a need to better understand how Mtb hijacks cellular processes like phagolysosome biogenesis, a classical pathogenesis determinant. A central feature to this microbial strategy is the manipulation of actin in Mφs. Here, we examine the role of microRNAs (miRNAs) as a potential mechanism in the regulation of actin-mediated events leading to phagocytosis in the context of mycobacteria infection. Given that non-virulent Mycobacterium smegmatis also controls actin filamentation to prolong its instracellular survival inside host cells, our approach was to perform a global transcriptomic approach to assess the modulation of miRNAs upon M. smegmatis infection of the murine Mφ cell line, J774A.1. This approach yielded miR-142-3p as a top candidate to be involved in the regulation of actin dynamics required in phagocytosis. We unequivocally demonstrate miR-142-3p targets N-Wasp, an actin-binding protein required during microbial challenge. A gain-of-function approach for miR-142-3p revealed a down-regulation of N-Wasp expression accompanied by a decrease of mycobacteria intake, while a loss-of-function approach yielded the reciprocal increase of the phagocytosis process. Equally important, we show Mtb induces the early expression of miR-142-3p and down-regulates N-Wasp protein levels in both the murine J774A.1 cell line and primary human Mφs. As proof of principle, the partial siRNA-mediated knock down of N-Wasp resulted in a decrease of Mtb intake by human Mφs, reflected in lower levels of colony-forming units counts over time. We therefore propose the modulation of miRNAs as a novel strategy in mycobacterial infection to control factors involved in actin filamentation and other early events of phagolysosome biogenesis, such as the case presented here for miR-142-3p influencing N-Wasp activity during the phagocytosis process.

【 授权许可】

Unknown